DIY: Rebuilding an SR20DET

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This is a rough draft copy of my Motor Build How To. There will be placeholder text, placeholder images, and placeholder links as I flesh this out and get everything put together. I still need to upload images for the final assembly and fix wording. Also, there will be pictures taken from another SR build that I'm working on as I forgot to snap pictures of certain things when I was putting mine together

I'm making this thread in an attempt to give people an idea of what it is to rebuild a motor. I do not take responsibility if you put your motor back together and it doesn't work/blows up/falls apart. I highly suggest you download a factory service manual as it has step by step instructions for building and inspecting.

This will primarily be about putting the motor back together. I don't plan on giving a detailed summary on removing the motor from the car. I expect for whoever wants to use this thread as a helpful tips guide to be able to do things such as remove a motor and place it on an engine stand.

Lastly, if you don't agree with some of my methods, that's your right. If you have better techniques, by all means share them. Just don't berate me for the way I do things. I have put together my fair share of motors using some of the techniques listed below and have yet to have anything fail on me.

I would like to give a big thanks to my mentor, Jay, for putting up with me over the years and teaching me everything I know. If it weren't for his guidance, I would never be able to do something like what is written below.

For tools, I suggest you have a full complement of sockets, ratchets, allen wrenches.

Special tools needed:-Oil Seal Puller-Piston Ring Compressor-Rubber Mallet-Impact Gun-3M Gasket Surface Cleaning discs-Assorted picks-Valve shimming tool (further elaborated in the Head Assembly section)


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This is by far the easiest of the steps. However, you need to have good organization or you'll easily and quickly lose pieces. I prefer to take something like a coffee can or an old anti-freeze jug with the top cut off to put bolts in. Usually I'll keep one for exterior bolts and one for interior bolts. That way you can minimize the amount of dirt you get on interior bolts.

First, drain the oil out of the motor. You may want to do this while the motor's still in the car. Let it drip for a while so you can be certain you've gotten most of the oil out. Lesson number 1: You may think you have gotten all the oil out, but there's a quart still hidden in there ready to piss all over your shoes.

Remove the flywheel from the back of the motor and place the whole unit on an engine stand. I highly suggest getting a drip pan for your engine stand. It's a V shaped plastic pan that sits on the legs of the stand and will catch oil and coolant that drips out of your block. Your floor will love you for it.



The first major piece to remove would be the head.

We have a great resource for removing SR heads here.

Since my block didn't come with a head, I felt it best to link mrzbala's How To since he has actual pictures for removing it.

When you get ready to place your head off to the side, set it down without cams in it to keep the valves all closed and prevent bending any. You can also loosely screw the bolts back in for the cam towers so you don't loose any of them. If you notice, they are marked 1-5 with an I for intake and E for exhaust.

Rotate the motor over and remove the lower oil pan. When you do rotate the motor, be careful as there will still be oil and coolant pooled in the passageways and it will pee allover you. Then remove the baffle plate inside the oil pan so you can access the bolts holding the upper oil pan in place. Remove the upper oil pan, starting from the outer most bolts and working your way towards the center.

Once the bolts are removed a few taps from a mallet should break the silicon seal and the oil pain will lift off.

There is another, smaller baffle held to the main support girdle. Go ahead and remove it as well. There are also three bolts holding the oil pickup tube in place. 2 to the front cover and 1 to the girdle.

Next, remove the front cover. I find it best to at least remove the water pump pulley so you can access the front cover bolts. Another few taps from the mallet should release the front cover and you have full access to the timing chain.

Just to clarify some terminology, I'm going to use the terms Nissan uses in the service manual for the timing chain guides. They list the long straight guide as the tension guide as its the guide over which the chain is being pulled on. They call the guide that the tensioner pushes on the slack side. Kind of opposite of what we call them.

Remove the tension side guide. With this guide out of the way, the chain should be ready to pull out. Lastly, remove the slack side guide.

Mention what size allen bit is needed

Next, we remove the pistons. You'll want to rotate the crank over so the rod bolts are accessible around the girdle and then break the nuts off the end. A lot of times the rod cap will want to stay in place, so if you take a rubber mallet or a wooden handle and tap the rod bolts, the cap will come loose.

When you remove the cap, take a long slender tool that won't scratch metal surfaces and start to push down on the rod bolts to seperate the rod from the crankshaft. I prefer a wooden handle of a hammer or ball peen. They're usually very slender and easy to maneuver in the tight confines of the crank case and they won't scratch anything.

Once you have the rod free, you can either push down on the piston itself or continue pushing on the rod. Just be careful not to let the rod scratch the cylinder bore. Push the piston until it comes out, and be prepared to catch the piston. The last little bit before the compresion rings clear the deck usually seems the hardest to me.

Repeat that 3 more times, rotating the crank over so you have easy access to all the rod caps. A magnet does come in handy for retrieving rod caps and rod bolt nuts.

Starting from the outside bolts, break the bolts holding the crankshaft bearing caps down. Break the outside pairs, then the next 2 pairs in, and then finally the inside pair. Once they're removed, you can lift the girdle off.

Remove the rear main oil seal carrier to make it easier to remove the 5th bearing cap.

To get the bearing caps out, I find it best to rock them back and forth a little bit and then with a bolt threaded into the hole on top of each, you can use a pair of prybars to lift them out.

Once the bearing caps are out, you can lift the crankshaft out.

Remove the oil squirters for the pistons and the baffle plate next to cylinder #4. It seems random as to if Nissan put a mesh screen in with the baffle plate, as I've had multiple blocks apart and only seen the screen in one or two blocks.



If you're taking your block to be cleaned/machined and checked and decked, I recommend removing the water housings and the oil filter plate. There are 3 water housings. The water neck on the head, the sensor housing on the head, and the thermostat housing on the block.

Also, remove the o-rings for the front cover oil passage and the two on the oil filter plate.

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At this point, I recommend finding a good, reputable shop to hot tank your block and head. Then have them check the deck and head for straightness. If it's out of spec, they can shave a fraction off to re-obtain straightness.

Also, I like to use cold carb cleaner dipping solution to clean up nasty engine internals. Pistons and rods can definitely benefit from this. Cold carb dipping isn't as good as a hot tank bath, but it's cheaper and you can do it in your own garage.

Since my rebuild block had slightly damaged cylinder walls, I bought Mahle pistons in a .020" overbore (that's .5 mm for the metric crowd). The shop required the pistons so that when they bored the cylinders, they had the end product there to test fit.

While the block was at the shop, I did the job of demounting my old stock pistons from the stock connecting rods as I'd be reusing the connecting rods.

To de-ring the pistons, just simply take a pick and, starting with the top compression ring, pull the ring out and up around the crown of the piston. Then simply walk the rest of the ring out. Remove the second ring next and then both oil control rings. Finish by removing the oil ring spacer.

:Walking the old ring off

Mark the rod's front side with a punch marker of some kind. Nissan did do a good job of putting the lettering on each rod on the rear facing side of the rod, so the smooth side is front.

Marking the front with a spring loaded punch

You must remove one of the two c-clips holding the wrist pin in place. A pair of c-clip pliers are necessary to compress the c-clip and pull it out.



Once the clip is out, you can take a drift and tap the wrist pin out. Be careful not to scratch the bushing race in the connecting rod or the piston if you're reusing any of the old parts.



Repeat for the other 3 pistons.

Inspect the small bushing that the wrist pin slides through. You're looking for any burrs that may need to be smoothed down with emory paper.

The picture is a little blurry, but this bushing required little cleaning. With all of the rod bushings, I lightly ran some emory paper over the surface to clean off any gunk before soaking them in cold carb.

I usually go ahead and dip the rods in cold carb over night at this point. It cleans the bearing races and gets all the old oil off the metal.



To figure out what size bearings you need, you'll need to examine the crank and the block. On each are some stamps that indicate what diameter the bearing housings and crank journals were machined at the factory. So long as you haven't spun a bearing or had machine work done, these stampings will be accurate.

First, look at the block. In the back corner will be a stamp.

The markings will look like this.

This series of numbers is a code that says that each journal is a particular inner diameter on the block. The first digit is the first journal and each one after that is the following journal.

Next, you look at the front of the #1 counterweight of the crank. Nissan says that there are two different styles of stampings on their counterweights, I have only seen the one I highlighted in red below.



This is a very light engraving, so if you didn't have your crank tanked and cleaned, you'll probably need to wipe the oil residue off to see the stamp.

The most common style has two rows of numbers. One row has 4 digits, the other has 5. The row of 4 references the connecting rod bearings, while the row of 5 is for the main bearings.

For our example, we'll assume that the crank has a stamping that looks like:001001320

And our block has the stamping:11123

Nissan supplies a chart in the service manuals that you cross reference the stampings to get a bearing grade.

You take the stamp from the cylinder block and find it along the top row, then find the crank stamp on the left column. Then trace them till they cross each other. That is the bearing grade you need. Tip: It's simple addition.

For example, we're trying to find the Number 3 journal size. On the crank we have 0 1 3 2 0 and the block has 1 1 1 2 3. The number 3 is a 3 for the crank and a 1 for the block.

I highlighted the column and row for the grade numbers and where the intersect. Our grade 3 and 1 crank and journal will require a Grade 4 bearing.

Finding rod bearings is easier. The row of 4 digits on the crank is all you need. The left most number is the bearing grade you need for the number one connecting rod, the second is number 2, etc. The reason you don't have to do a cross referencing for the rods like you do for the main bearings is that Nissan considers all rods to be identical for the races. There are stampings on the rod indicating other than the cylinder number stamp. These stamps are to denote what size wrist pin bushing is needed.

When you order bearings from Nissan, you will need to order 2 bearings of each kind for the rods as Nissan sells them in bearing halves. When you order main bearings, you will get both halves.

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The first step for assembling the bottom end is to get the pistons ready to go in.

I went ahead and gapped my rings at this point. Most manufacturers will pregap the rings, but it never hurts to check. To check, simply put the ring down the bore of the cylinder a little ways and use a piston to push it flat for about an inch of travel.

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Here I push the ring down with the flat side of the piston.

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You can see the gap of the ring.

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A set of feeler gauges are needed to find the proper gap.

Take your feeler gauges and start inserting thin feelers in until you get resistance, and ultimately can't put a gauge in. You're looking for the feeler that gives the least resistance without being too small.

My Mahle top rings were preground to a .015" gap, but according to their chart, I needed the top ring to be at a .018" gap. The second ring was preground to about a .016" gap, but needed to be ground to about a .021" gap.

Factory ring specs are listed in the S14 service manual, but I'll put them up here.

Ring 1 - 0.20mm-0.30mm with an upper limit of 0.39mm
Ring 2 - 0.35mm-0.50mm with an upper limit of 0.59mm
Oil rings - 0.20mm-0.60mm with an upper limit of 0.60mm

Mahle has it's own set of gapping specs. These are listed on a sheet of paper supplied with the pistons and rings. Some calculation is involved since the specs are based on bore size and whether or not the motor is under forced induction.

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To grind the rings, I used this ring grinder. It's a little old and worn, but it gets the job done.

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You hold the ring to the backplate like this and push down. The pins will force the ring ends to gether and the wheel has a file on it. Turn the wheel towards the backplate to start grinding. If it's a new grinder, or you're unsure of how much a turn will take off, I recommend only turning the wheel 1/4 to 1/2 turn increments and remeasure the gap of the ring by placing it back in the cylinder like before.

Grinding is tedious and will take alot of trial and error to get the gap set perfectly. Aftermarket rings tend to be made of tougher metals than OE rings, so they will take longer to grind.

If you had your block machined for bore diameter, the shop more than likely honed your block. If you didn't send it off to the shop, then you should hone the block yourself, or have someone do it for you. I don't want to cover the actual honing process just because it seems to be a very touch and go process to me. You have to get a feel for how fast the spin the honing stones and to move them up and down in the block. It's not something I feel I can easily convey over the internet.

If your shop didn't hone the block, I recommend waiting until after you check the ring gaps to hone it. It's a personal preferrence to do it before or after you gap the rings, as it doesn't really affect seasoning of the piston rings. I recommend waiting if you can (I didn't on this build because my shop honed it when they bored it out) only four soundness of mind and you can be absolutely certain there isn't any marring of the hone pattern when you install.

I had dunked my rods in cold carb cleaner and they had cleaned up rather nicely. While I attach a set of Mahle pistons to the stock rods, the process is no different than any other piston/rod combo you can put in an SR20. I did go one step further since I was reusing my old rods; I replaced the rod bolts. Rod bolt failure can be a nasty end to a motor, and while I have yet to see a Nissan rod bolt in an SR stretch and break, it's never a bad thing to be too safe. I had considered ARP rod bolts, but they would have required expensive machining to ensure the rod ends were still round, and by that point, it would have been more cost effective to have gone with a set of performance rods.

I recommend replacing the rod bolts first if you're going to replace them. If you wait till after you've attached the piston, the piston tends to get in the way and make the process clunky.

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Clamp the rod in a vise. I like to use soft jaws to avoid marring the rod.

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Thread a rod nut on until a thread or two show above the nut. You want to do this to prevent warping the bolt and having it get stuck in the hole. The bolts are press fit and if they're distorted, they tend to not want to come out. Take your mallet, a deadblow is preferred, and give it some good whacks. Once the bolt starts to move, it should come out with a few more whacks.

Remove the rod from the vise and insert your bolt into the hole, making sure it lines up good. A few light taps will get it started and then you can start putting some force into hitting it. The bolts tend to stick the last centimeter or so, so I take a long drift or chisel and use it to finish the job. With the piston not on the rod, you may have some good swinging room to not need a drift.

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I had to use my fingers to keep the drift from contacting the piston. When it did make contact, it created burrs that needed to be filed off.

Repeat the process for the rest of the bolts you intend to replace.

Take the supplied wrist pin and test fit it in your rod's small end bushing. If it's a tight fit, take some emory paper and work out any left over gunk and burrs until the wrist pin slides in. You want to avoid any binding

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Install one c-clip. The Mahle's are a bit of a pain as they use rounded spring steel for their retaining clips. These clips have no eyelets like the stock clips, and require some finesse and religion to get in place. I had to take a set of flat nose pliers to compress them and then try to wiggle it in place making sure not to launch the clip into orbit, and subsequently a distant, dirty corner of the shop. The first clip is leaps and bounds easier than the second clip as you can maneuver it in sideways and all other positions to get it in it's groove.

If you're using clips with eyelets. I hate you.

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Slide the wrist pin into the opening with a c-clip and push it through until it slides into the middle opening. Position your rod so that the front mark on the rod matches the front mark on the piston.

Note: Some pistons don't have a front marked such as these Mahles. They were cut short enough that the skirt doesn't need a cutout for the oil squirter. CP, Wiseco, and Nissan all have a cutout for the squirter. That's why it's important to have the front lined up properly.

Push the wrist pin through the rod bushing and into the other side of the piston. If you run into a little resistance, you can wiggle the rod around to aid pushing the wrist pin in. The last little bit usually requires a drift to finish the job.

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Install the second c-clip and you're done.

To install piston rings, you should install them in this order:-Set the oil spacer (accordion ring)-Bottom oil ring-Top oil ring-Second compression ring-Top compression ring

I went by Nissan's ring diagram for positioning even though Mahle's is set up a little differently. It's not a huge issue, so long as your using a known good positioning chart. The primary thing you want to make sure is that your compression ring spaces are 180 degrees apart.

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This is the chart Nissan provides for ring position.

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To install the rings. Ensure which side of your piston is the front and set your oil spacer ring based on your diagram. Don't allow the ends of the spacer to overlap. They should be touching.

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Then take your bottom oil ring and set one end in position while the rest of the ring is bent upwards. This will keep from stretching/breaking the ring and you just have to walk the rest of it in place.

Repeat walking the rings on for the top oil ring and the compression rings. Be sure to watch for what side is up on the rings. They're usually marked in some way.

Setting the crank in is rather easy.

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First, install the oil squirters and baffle plate.

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Then install the bearings into their spots making sure to line up the oil hole and notch.

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Then take some assembly lube and apply it to each of your bearings.

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Set the crank in place.

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Set the thrust washers in place on the #3 main bearing. The thrust washer minimizes shifting of the crank forward and aft. If you notice, there are two channels on one side of the washer. The point away from the bearing. The best way to get them in place is to lay them on the curve of the journal for the crank and roll them into the slot.

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Once they're in, they should be hidden like this. I pointed out which way the large ends should end up.

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Snap the bearing cap halves into their holders. Again, make sure you note the notch.

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Line up the notchs of the bearing halves. They should be on the same side as each other when you install the bearing caps.

At this point, while the caps are loose, you can set the girdle on top of the caps and start the main bolts. Once the bolts are started, I usually take a mallet and gently start tapping the caps down into place.

You can also use the bolts to gently snug the caps into place.

Once all the caps are snug and in place, go ahead and tap the tops of each cap to help it seat better.

The Nissan manual has the proper torque sequence in it. If you're using ARP main studs, though, use their torque procedure but use Nissan's bolt sequence.

You always start with the middle bolts and then work your way out such as in the following picture

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Notice how the middle two are the first two to be tightened, then the pair to the right, then the pair to the left. Finally the outside pairs are tightened last. Always follow that order. This is especially importance since you're working on an aluminum block.

In between each portion of the torque sequence, I tap on the top of each main cap. This helps to keep the bearings seated and will ultimately help them spin freely once you're done.

The first torque setting you should do is 22 lb/ft +- 2 lb/ft (20-24 lb/ft)

Next, if you have an angle wrench then you're good to go. If not, then you will have to make a mark on the main bolt. Then, using an angle finder, make a second mark on the girdle at 75-80 degrees clockwise from your bolt mark. Take a breaker bar and tighten until your bolt mark lines up with your girdle mark. Wipe the markings clear.

Completely loosen the bolts.

Retighten the bolts to 26 lb/ft +- 2 lb/ft (24-28 lb/ft)

Make your marks on your bolts again and measure out to 45-50 degrees clockwise. Tighten the bolts again until the marks meet.

The point of this torque sequence is to stretch the main bolts out to help them grab better. Torque to yield would be the term. We've all heard it before.

If you decide to gauge it by eye, you're doing so at your own risk. I've done it before and have had no ill effects, but not everyone has a good eye for angles.

Now spin the crank (use a wrench on the pulley bolt) to see if there is any binding. If it spins easily, you're ready to put the pistons in.

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Install the bearings into the rods and caps, making sure to match up the notches on the bearings to the ones in the races. The rod caps will have markings on the side for which cylinder each rod goes to. You want to make sure the cylinder # markings line up between the rod and cap.

Rotate the crank over so that the journal for the piston you are installing is facing down.

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This is my favorite type of ring compressor. It just seems to be much easier to use than the ones with the worm gears.

Apply some assembly lube to the rod bearing and put the piston in the ring compressor. With a mallet handle (again, I prefer wooden handles) tap the piston into the cylinder bore. Once it clears the ring compressor, push it all the way down, being sure to watch out for the oil squirters. An errant rod will break them easily.

Once the rod is on the crank, you can rotate the crank to an angle to make installing the rod cap easier.

When tightening the rod bolts, first tighten the nuts to 9-11 lb/ft. Then either tighten them to 65-70 degrees, or 28-33 lb/ft. I prefer the torque setting as it's easier to do.

Repeat for the other 3 pistons.

Once you have all the pistons in place, rotate the crank over a few times to check and make sure the pistons are all smoothly moving and that there are no clearance issues. If you're running aftermarket pistons, it's especially important to watch for clearance issues.

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Set the crank so that the number one piston is at Top Dead Center.

There are a few different procedures for installing the front cover and head. The service manual tells you to put the timing chain in and then the front cover before placing the head in place. I prefer to do it backwards. Primarily because you can't confirm if the chain is going to stay in place on the crank sprocket and it's too easy for the chain to droop and get off time by a tooth.

Make sure the cams are out of the head to avoid any clearance issues with open valves. You don't want to bend any.

First, install the dowels in the block's deck. These are guidepins that help the head sit in place. There are two of them.

Set it in place on the deck and then, using a rubber mallet, tap it down into its holder.



Before you install the headgasket and the head studs/bolts. You may want to check the holes and make sure there isn't a lot of crud stuck in them. Since my block had been hot tanked, the cleaning solution had dried out in the holes and left deposits on the threads making it very clunky to install my studs.

The solution was to take an old head bolt and use a grinding wheel to completely grind off the threads on one side. After you run a die on it to straighten the threads back out, you get a bolt that will move on the threads easily and since it has a side with no threads, all the junk just builds up there on the bolt. I had to use this method as I had no taps long enough to reach in.

At this point, most people would install the ARP studs. I was informed that installing the studs at this point would make putting the head on next to impossible. Nothing sticks up perfectly straight and the head will get cocked on the studs at weird angles and get stuck making it hard to get back off.

So I go ahead and lay the head gasket in place.

Then I set the head in place. It's doable with one person, but infinitely easier with two. Just guide the head down and let the guide dowels put the head in place. You'll know you have them lined up when the head clunks down easily.

Once the head is in place, go ahead and start threading your head studs or bolts in place.

For stock head bolts, follow Nissan's torque to yield stretching procedures. the JDM service manual says to coat the threads of the bolts in motor oil before installing.

Insert torque procedure

For head studs, first coat the first few threads in ARP's supplied lube. Their torque procedures are based on having that lube on the studs. You don't want to overload the threads with lube, though. So don't be too generous. It would just be wasted lube.

You'll need a SIZE allen wrench to get the studs all the way in place.

You'll know when they're seated completely when they only stick out this far

You don't want to put any torque on these. Hand tight is good enough.

Next, place the washers in place, put lube either on your nut or on the stud, and thread the nut in place. ARP lists 75 lb/ft of torque is needed, however, I find it best to start at either 40 or 50 lb/ft of torque and work up to 75 lb/ft in stages.

Just make sure you go in proper order, starting with the two center studs and working your way out:

Installing the Hydralic Lash Adjusters is the next step. First, you should bleed them as you have easy access to them, and we all hate the sound of ticking lifters.

Take a flat pointed rod that's big enough to fit in the top hole of the lifter. I found a punch like this one to be the best.



When you insert it, you're trying to place the tip of the rod on top of a check ball in the bottom of the lifter

The check ball normally allows oil to enter the lifter when the plunger is depressed, but won't let oil back out. However, oil can seep out of the lifter if it is left upside down.

Place the lifter in a cup of oil. Anything will work so long as it is deep enough and you can get your fingers in to work with the lifter. Push down on the check ball with your rod and repeatedly push down on the plunger. It will suck oil in and you should see bubbles escape. Continue until there are no more bubbles.

Before you install the lifter in its hole, pour a few drops of oil into each lifter hole. This should help the lifter keep its prime and it makes install easier. Just be careful as you will shoot oil out of the tiny oil hole in front of each lifter hole. If you push the lifter in too hard/fast you'll spray yourself in the face with oil.

Proper shimming of the head requires that you place the rocker arm guide, which is the shim with the center cut out of it on top of its valve, and then use a dial gauge to measure the distance from the top of the guide to the top of its adjoining valve stem. Nissan requires a special dial gauge stand to make this work, and that stand is pretty much impossible to find anymore.

There is hope, though. Custom Steel makes a dial gauge tool.

It's not cheap at $175, but considering that you have your head shimmed properly, the price seems worth it. Especially if you and your friends build SRs often enough. Email Pat at [email protected] to order. His turn around is about 2 weeks from receipt of payment.

I assembled the head originally without the aid of the dial gauge tool. It will be reassembled properly during the 1,000 mile check up. In the meantime, I opted to pair shims up to the rocker guides by measuring their thicknesses.



It's not exact as it still allows the difference in valve stem height, but it's more accurate than what 90% of the SR community does, which is to blindly put shims and rocker arm guides without checking any of their thicknesses.

Next, set the rocker arms in place.

Finally, you can install the cams, minus the cam gears. You will want the dowel pin on the exhaust cam pointing straight up, and the dowel pin on the intake cam pointing to about the 10 o'clock position.

You can see the dowels right above each cam bolt.

Make sure you put assembly lube in each of the cam journals.

each cam cap is marked 1-5 and with an I (intake) and E (exhaust) with the #1 caps being the front caps. They should also be marked with an arrow for direction, but the caps will only bolt in one orientation.

When tightening the caps down, I recommend using a 1/4" drive ratchet. You will not overtighten the caps with a 1/4" drive, but you won't leave the bolts loose enough to rattle out. The factory torque for these is measured in inch/lbs, so it doesn't take a lot to torque them in place. Once the aluminum of the head heats up, the threads will expand and hold the bolt quite well if tightened adequately.

Start tightening the #3 cap, and then move out to #s 2 & 4, and then 5 & 1.

You will also want to go ahead and put the bolts that hold the front cover to the head in their holes. Once you install the exhaust cam sprocket, you will not be able to insert the bolts.

Next, place the chain in its spot. There are 3 silver colored links. The two closest to each other go on top to the cams, the one lone link is for the crank sprocket. Once you put the chain in place, you can bolt the exhaust side timing guide (tension guide). You can bolt the intake side timing guide (slack guide) anytime you want.

Line up the bottom link with the mark on the crank sprocket.

Then install the intake cam sprocket and feed the chain onto it. You don't have to torque the cam sprocket just yet, thread it in far enough to keep the sprocket in place.

Next, take the exhaust sprocket and line it up with its chain link and then place it on the exhaust cam. To get the cam to line up perfectly with the sprocket, you may have to turn the cam over a few degrees to get things to line up perfectly.

The cams lined up with their marked chain links.

To torque the cam sprockets down, take a 1 1/16" wrench and use it to hold the cams still. A friend comes in handy for this part.

Then take your torque wrench and tighten the bolts to 94-101 lb/ft having your friend hold the cams still. I like an even 100 lb/ft.

Once you are satisfied with the way the timing assembly is put together, go ahead and install the timing chain tensioner. If you're reusing an old tensioner, there is a small cam above the retractable arm. You will have to pull it up and then press down on the cam until you can secure the hook on the peg.Insert image of the tensioner

Insert the tensioner and bolt it in place. The hook will pop off the arm and if you rotate the crank back and forth, the arm should pop out, putting tension on the chain.

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The last little bit is just buttoning the last few pieces together.

Remove the crank shaft pulley bolt and the oil drive spacer.



Next, you'll want to prime the oil pump. Vasoline or some other type of thick petrolium such as gear grease is best for doing this. Remove the cover to the oil pump and start backing the gears with grease as well as the openings in the pump. Once you have satisfactorly packed the pump, replace the cover. I suggest putting a dab of blue Locktite on each of the screws, especially if you don't have a phillip's head bit for a ratchet.

Install the front cover O-ring in the block. When you put it in, it's best to apply a little bit of oil to the O-ring to help it seal.



Next, you'll want to apply your silicon gasket maker. I was introduced to Toyota's brand of silicon gasket maker years ago, and I find that it to be one of the best I have ever used.

I usually lay down a bead of silicon and then go back and spread it out. This helps reduce thin and thick spots and promote an even seal.

The initial bead.

After I spread it out evenly.

Apply the silicon to the block side and head side of the front cover. While you're at it, apply some gasket maker to the front of your headgasket where it seals to the head.

You removed the oil pump drive to allow you to maneuver the front cover on without damaging the headgasket. If you try to install the cover with the pump drive still in place, you run the risk of crumpling the headgasket.

You may need to use a magnet to hold the front cover to head bolts out of the way while you do this. Once everything looks to be aligned up correctly, install the cover bolts. You should also wipe off any extra gasket maker that seeps down to the oil pan mating surface.

Once you have the cover bolted in place, rotate the oil pump so you can slide the drive spacer back in.

Ignore the hair. The guy that owns the shop I do my work in has a very hairy dog that sheds all over the place. You learn to cover up your work when you're not doing anything, but it's impossible to de-fur everything

Install the rear main oil seal into its carrier. One thing to note, if your seal doesn't come packed with grease already, take some gear grease and spread it inside the seal. I use a small piece of wood to evenly hammer my seals into place. There is a lip to keep the seal from falling through. Some carriers were made with extra tabs. Make sure the seal is pressed in and flush with the lip.

Apply some gasket maker to the carrier and bolt it in place, wiping off any excess that squeezes out to the oil pan mating surface.

When installing the oil pans and baffles, I only turn the motor halfway over. It reduces the chances of the lifters getting air in them, and you don't want to have to pull them back out, do you?

Install the baffle for the main girdle beam.

Install the oil pickup. The small M6 bolt that holds the brace to the girdle has an extra washer on it. Otherwise, it looks just like the other oil baffle bolts. Nissan updated the gasket for the pickup from the O-ring type to an actual gasket. Whatever you use, make sure you install it. The pickup will not seal to the pump otherwise and it won't have good suction.

Install the upper oil pan. Spread silicon over the mating surface and then start bolting it from the center bolts, and then work your way out evenly.

Install the oil pan baffle.

Lastly, install the lower oil pan.

Install the oil filter block. Remember to apply oil to the two O-rings.



Apply gasket maker to the thermostat housing and install it.

When installing the thermostat, it's important to make sure it doesn't slip down and cause the water neck not to seal properly. Install the water sensor housing for the head as well.

The jiggle valve points up.



Install the sensor block.





The water lines should go on like this. All of the little nipples need to be oriented in particular directions to supply water to the IACV and throttle body. Before putting the intake manifold on, it would be wise to install the long hose that feeds from the nipple behind the sensor housing block to the throttle body. Position the hose so that the end without the extra padding is on the water line nipple. I tried it with the other orientation, and the hose doesn't seem to make the bends as nicely.

At this point, your block is done and all you need to do is bolt your manifolds on and install your flywheel and clutch.

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The oil you should use for the break in should be a non-synthetic oil. The reason that was explained to me was to allow the rings to seat. Synthetic oils are less likely to allow the rings the opportunity to seat. Recently, more people are reporting about the lowered ZDDP levels of current API standardized oils, many people are switching to diesel oils and oils for 4 cycle motorcycles. Read more about it here

When I put a motor in a car for, I like to leave the valve cover off.A) You won't scratch it up with the hoist chain. If you spent money on getting your valve cover prettied up, I would highly recommend not installing it till after the motor is in the car. You will need to find something to cover the head to keep debris from falling in it though.

B)When you put oil in, you can pour it over the cams and down the timing chain to make sure everything is getting lubricated before the oil makes its way to the oil pan.

When you get ready to crank the motor for the first time, pull all the spark plugs out of the motor and crank it for a few seconds to make sure the pump builds a prime. Pulling the spark plugs makes sure there is no pressure on the bearings while they get their first taste of oil. Even with good quality, moly assembly lube, you want to be certain that you build oil pressure before you allow compression pressures to be present. You'll actually hear the motor speed up while you crank like this. It's kind of neat.

Check the oil after you first crank the motor to build oil pressure. You'll find a half quart or so mysteriously disappears. That's because the oil is making its way to the oil galleys and filling all the nooks and crannies in the motor.

Once you get the motor running and have the ignition timed in properly, let it run and idle for a bit to work any gunk through the cylinders and out the exhaust. You also need to let it warm up to operating temperatures to properly fill the coolant system anyways.

On your initial test drive, don't be worried if your car feels sluggish. The compression rings aren't seated yet, and that tends to make the car feel like it's bogging.

Once you've put a few miles on the motor, take it out to a nice stretch of highway, preferably one with hills and get up to speed. Put the car in 4th gear at about 40 MPH. Then accellerate to about 60 MPH. Don't stomp on the gas, just gradually bring it up to 60. When you reach 60, let the car coast back to 40. Repeat this process about 5-10 times. This puts a varying load on the motor and helps the rings to seat in sooner. During my test drive, I could actually feel the motor gain more power as I did this.

During the break in period, just drive the car normally. You don't need to baby it, but also don't go out and gun the throttle constantly. Every motor is different in its break in time, but the average time does seem to be about 1000 miles.

Change the oil at the 500 mile mark. As the rings and bearings seat in, you will get tiny metal particles in the oil, and you will need to change to clean oil and filter after the first 500 miles.

Retorquing the head after the 1,000 mile break in has been suggested to me. This is really only necessary for those that use metal headgaskets. My friend, who has well over 30 years of experience wrenching on every Japanese brand has found that when he doesn't retorque the head, the possibility for leaks increases. A lot of times, a fresh rebuild needs to sit and season itself, and the initial torque won't be the same after the break in procedure. By retorquing, you effectively reseat everything after it's had a chance to move and stretch. To do it, you will have to pull the cams out to access the head bolts/studs and break them. Don't loosen them, just take their torque load off. Then go back through and retorque them in order. If you zip tie the timing chain to the cam sprockets and leave the tensioner in, you should have little worry of the chain slipping time.

This is the first version. There's still more to add and clean up. So be kind and patient as I flesh this write up out and make corrections.

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RCCC_DRiFteR
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Ok, this has been quite helpful so far. The only think I don't know is how do I know what Connecting rod Bearing I need to order?? On Phase2 it has 3 different Grades. 0 - No Color, 1 - Black, and 2 - Brown. This is my 1st build and i wanna make sure I buy the correct bearing. So I wold like to know how I figure out what bearings are appropriate for my block. Thanks

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Hijacker
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Oops. Forgot to put that in there. I'll add it in when I get home this evening and can photoshop up the pics I need

white90esex
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good stuff

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RCCC_DRiFteR
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I replied to your email. It's all 0 0 0 0 for the combination. So all 0 grade bearings then right??

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RCCC_DRiFteR
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so wait, i cant find the code for the crank to compare it to the rods.. that combination is on the rods, but idk cant find the crank numbers to compare to. or are those the four digits i need that are on the connecting rod to order the proper rod bearing grade. . .HELP!!

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positron1
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This is very helpful, thanks!

slik_s13
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thats what im talkin about. good job

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RCCC_DRiFteR
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Gee Golly I hope 0 grade is the right thing. . .

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Pics!! Bump

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RCCC_DRiFteR
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Ahah! Found the lil serial numbers!!


858slider
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what should you DEFINATELY replace when rebuilding? I.E. water and oil pumps, bearings, connecting rod bolts, etc. I'm sending my head to a machine shop monday. Also are rocker arm stoppers necessary for mild upgrades? I have a GTIR T28 any parts different with this turbo? thanks in advance for all replies.
Modified by 858slider at 7:27 AM 3/21/2008

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So long as your oil pump and water pump are in operating condition, there's no need to replace them.

I recommend that you replace rings and bearings at the bare minimum in a motor rebuild. Your machine shop will probably replace the valve stem seals and tell you if any valves/guides are out of spec and need replacing.

858slider
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forgive me but which rings and bearings are you referring to? the piston rings right? and which bearings? main, rear all? i'm not familiar with all the parts. I modified my o.g. post...pls review thanks

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Bearings mean main bearings and rod bearings. rings mean piston rings.

rocker arm stoppers are items that help reduce the chance of the rocker arms jumping off the valves if you over rev the motor on accident. Any motor can benefit from them.

This is a motor build, not a turbo discussion. I only deal with the motor in this thread as the turbo has no bearing on how the internals are assembled.

858slider
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oh sorry, thanks for the info

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RCCC_DRiFteR
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Thank you for everything Hijacker!!

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efrain240sx
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I got a "Q". would a unbalanced crank cause engine knock ? I ask because I just rebuilt my bottom end to OEM specs. I had the cylinders homed and used oem rings slandered size, got new oem crank & rod bearings, and every thing was torqued down to spec. But now I have this loud clunking noise coming from the bottom end. The clunking is loud and you're able to feel it if you put you're hand on the engine and rev it, and the safc picks it up to as engine knock ( note SAFC i just their I have not tried to tune with it). Does any body have any clue on what it could be? oh and the reason I ask about the unbalanced crank is because I didn't get it balance when I got the new bearings, I just got bearings from what the block&crank originally came with. Thanks P.S nice work again hijacker

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RCCC_DRiFteR
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I'm gonna look around for something like that cause I wanna avoid that from happening

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efrain240sx
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man I'm tired of working on my car I just want to blow it up at THIS POINT

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You reused the old pistons and rods? There shouldn't have been a need to rebalance the rotating assembly. You usually get everything balanced when you change out anything in the rotating assembly (pistons, rods, etc).

Being out of balance will generaly cause odd vibrations under load as well as accelarated bearing wear.

If I were you, I'd pull the oil pan and investigate as to what's causing your noise. I'd also pull the valve cover as well and take a look down there.

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efrain240sx
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Yeah I reused the rods & pistons. At 1st I thought it was the trans, because when I would listen to the clunking with a stethoscope the noise would sound like if it was coming from the trans. So I got me a KA trans, pulled out the engine and trans changed over the bell housing from the old SR to the KA trans ( note when inspecting the SR trans I didn't find any thing wrong with it, in fact it looked better and cleaner then the KA trans that I was going to put in) but I did screw the trans part, I kind of knock a gear in when putting the tail of the trans back on . So I do have to take it back out to fix that problem. I also took the opportunity that the engine was out and riped it a part to check the bearings and cylinders. The cylinders had nothing wrong with them, no scratches or anything on them. The bearings looked OK I guess, they seemed to have just a little bit more wear on the outsides of them. After I fix the trans problem I'm going to try to get a hold on a wide band to see if I'm not running a bit lean.

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homeslicej2
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Bart, I might just have you rebuild my motor. Great thread.

RPS13 DRIFTER
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has anyone ever had problems with boring out the block?.20 isnt much but the cylinders are really close to the water jackets in between each cylinder.so if i bored it .20 over i need 86.5 mm pistons?


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