FINALLY! The engine (re)Build BEGINS!

[Arrow]

Hello fellow NicoNauts!

It's been quite a while since I last posted in the forums here. I have finally reached a point in which I can get some serious work done on my '90 hatchback! I am planning on doing a basic stock rebuild of a spare engine that I have lying around. It's been sitting for the last 5 years untouched and 3 of those years outside under a tarp... Right now all I am wanting is an engine that works and doesn't leak or burn any fluids - my car currently leaks every fluid in it and burns oil rather badly (215k miles). I am planning on repainting the car and I don't want a nice new paint job to get oil and fuel on the rear bumper, and I don't think the current engine will last much longer...

So onto the point that everyone looks for: PICTURES!

Now here is a challenge for all of you: How many miles are on this engine??

::EDIT:: Answer: 160,XXX miles!!!! Can you believe it?
















Modified by Arrow at 1:15 AM 6/9/2009

[sloweighty]

it looks like it has no more than 100k or less because the inside looks so clean and why are you going to rebuild this motor.......it looks fine to me......you should open the oil pan and check the piston bores to make sure everything looks good before you rebuild a stock motor back to stock........can you also post pictures of your car.

[slidestyle69]

if ur gonna rebuild the sohc, why not jus buy a good running dohc?

[nightsleek240coupe]

dohc's are way overated. swaping a motor for 15 extra hp? there's parts out for sohc motor,buld it and boost it,and make it look like this.

[Arrow]

haha! Keep guessing for the mileage! I will probably state the mileage later on tonight...

As for why I'm rebuilding, I want to get some experience before I move on to a more complicated build and while I am at it I will do some gasket matching and maybe a bit of porting on the head, intake, and exhaust. I have access to the equipment and figured that it would be some free power - though I won't get much since right now I am not planning on upgrading the cam (but that may change).

I am beginning to think that I didn't need to do a rebuild, but I didn't trust the engine to run well, not burn oil, or leak oil all over a freshly painted car - just for reference though, the car hasn't been painted an looks like piss (hence the desire to repaint). I've just removed the head to take a look at the pistons and cylinder walls... So without further ado, MORE PICS!

You can see the carbon / sludge on the tops of the cylinders (easily removed though):

Factory cross-hatch still visible!

Underside of the head:

Close-up of a cylinder head:

A look inside an intake of the head:

So Continue to guess the mileage and feel free to give me any feedback that you have! My roommate and I just finished rebuilding his '93 Camaro Z28 a month ago (built the engine to be ready for a supercharger and right now w/o the SC on he's making about 350 rwhp)... So I'm not a complete newb to this stuff lol.

Oh yeah and here is a very old picture of the car after I re-ended a BMW

Now the front bumper and headlight covers are primer gray b/c I couldn't stand the cracking paint - but that is the general color and everything (crap faded oxidized purple lol). The previous owner had the car painted before I bought it by Macco (go figure) and I've owned the car for 7 years now...

[BearTrap]

Ahhhhhh, nice..... Reminds me of my rebuild of the KA back in 02.... Good times.

Your reason for rebuilding is the same as mine. I know my motor with my eyes closed and it taught me more about my car than anything.... You wont gain that knowledge by doing a swap.

Good luck and keep us posted on the progress!!!

I'm guessing 70k for the mileage. When I rebuilt my KA at 95k, it was starting to look toasty.

[Arrow]

Yeah I bought this engine from a local guy that had just put in an SR and needed the engine gone asap - so I bought the engine and transmission for $200 (5 years ago now lol) the transmission has a leak on the rear seal (I think) and the engine supposedly was running strong it's only problem is that it was overheating (broken hose) and the guy that sold it to me said that once he saw it start to overheat he had it towed to the shop for the swap... I just wasn't sure that the busted hose was the only issue with the engine and everything - hence the desire to rebuild....

[PyroTecK]

sohc build ftw... so underrated

[sloweighty]

when you said that you are going to gasket matching........i never heard anything good about this subject. I heard a lot of people doing gasket matching and something always happens. My buddy did it to his dual cam and he end up cracking the intake manifold and a piston. (Correct me if i am wrong)

[Arrow]

Gasket matching is when you cut out (grind really) extra material on the head, intake manifold, and exhaust manifold (sometimes not needed) in order to match the respective gaskets. You should never be removing enough material to crack the manifold or head. Gasket matching is generally decently easy, very safe, and rather conservative when it comes to port jobs - some people port out the gasket area enough that they need to cut out part of the gasket so that it doesn't impede flow.... I know that those extreme examples get a lot more challenging and difficult and I don't know of anyone doing those on 3 or 4 valve per cylinder engines, I've only seen them on domestic V8's

Hope this helps your understanding a bit better I'll throw up a picture a little later that will show what gets cut out for gasket matching.

[BearTrap]

Word. And you cant do that much damage with a dremel tool. Plus, it was on Horsepower TV the other day, so how hard can it be?!?!?!?

[24j0hn]

dohc's are way overated. swaping a motor for 15 extra hp? there's parts out for sohc motor,buld it and boost it,and make it look like this.

its not just for 15 extra hp... the sohc works harder that a dohc, therefore a dohc will last longer...

[thatonekid]

this inspires me to build my single cam

[cbt240sx]

Keep it up man!! I will be watching to hopefully gain a little extra knowledge about my Single Slamma!

[Arrow]

Hopefully this thread will become a driving force for me to get significant work done each day... I still need to figure out just how far I'm going to go on the rebuild and order gaskets and such. But there is more than enough work for me to get done on everything! I will post up again later on tonight after I pull the oil pan and take a look at the crank and I may even pull a rod or crank bearing to check the wear on them and determine whether or not I need to order new bearings.

Then comes cleaning the block extensively and getting that thing painted. I still have to work on cleaning up the intake manifold too.

And who knows, I may just get a performance cam to through in there - it will definitely make porting / gasket matching worth the effort! But it all depends on my finances (trying to rebuild this thing cheaply so that I can afford to repaint and get a replacement hood and bumper...)

[Fibre guy]

Boosted SOHC KA? DOHC are not only more reliable (IMO) but parts are more readily available.

[thatonekid]

Boosted SOHC KA? DOHC are not only more reliable (IMO) but parts are more readily available.

this build definatley inspired me but this guy has a good point

[Arrow]

Alright I got a little busy with a few other things tonight, but I managed to get the oil pan off and take a few more pictures:

Bottom-end w/o the oil pan - so that's what the thing looks like!

A close-up:

A look down and inside to one of the pistons:

Here is the timing chain and oil pump gears from the bottom:

And now the answer to my first question: How many miles are on this engine?

Answer: 160,XXX miles!!!!

That is why I had decided to pull things apart and see what damage had been done - by the looks of things this engine was pretty well maintained and it seems like the timing chain had recently been replaced along with the oil pan gasket.

More pics of the main bearings and other misc stuff tomorrow!

[sloweighty]

i know what gasket matching is....its just that i never heard anything good about it takes all.

[thatonekid]

kind of a late question but what kind of intake manifold you have????

[sommmatt]

I built my SOHC up this winter.

It was a fun motor to build.

f*** the haters.

I'm on the way to 400 horse right now.

btw... ditch A/C and emissions. Power steering too if you're manly. Cleans it up a lot.

[thatonekid]

sohc are awesome and i agree why swap out the whole motor just for 15 more hp

[Arrow]

There are reasons why I understand upgrading to a dohc - however I'm not planning on making this engine into a street terror.

And about A/C - That is the reason that I bought my motorcycle (last summer's expense) the A/C in the 240 has been nonfunctional for 3 years now.... BUT I hope to get it working in NC the summers can hit triple digits and the car turns into a sweat shop!

To answer the question about the intake manifold - mine is completely and totally stock. The pictures of the turbo'd SOHC are not mine and not my plans for this engine - and I don't know what manifold they used (possibly custom?)

So right now I've priced all the necessities to be replaced and I'm sitting at $285 - not too shabby if I don't say so myself. Anyone have some good places to get deals on quality OE style parts? Right now I just priced everything from Advance Auto.

::EDIT:: Oh and about gasket matching... I have only heard and seen good things come from it (granted on domestics). I have 2 friends who have ported and/or gasket matched their heads and manifolds and have had no adverse affects what-so-ever. My roommate and I even gasket matched his LT1 for his Camaro and everything is going fine and dandy right now and he's making some pretty impressive power (not dyno'd yet though - we'll wait to get the supercharger on for that one )

[Arrow]

Alright guys, time for another update!

Right now I have the entire engine tore down - man is this cast iron block heavy!

Anyway, on to the pictures!

Here is the block and the main bearings:

The front 3 main bearings:

The back main bearing:

Here's a close-up of the most worn bearing - the front main:

Here's the crank and pistons/rods:

And finally here are 2 of the most worn rod bearings:

SO, what do you guys think? I figure that I will start prepping this thing to be painted and get everything ready to go back together hopefully within the week! (depending upon how long it takes the rebuild parts to get here)

If anyone would like pictures of anything specific or if you've got any questions or concerns feel free to let me know!

Now it's time to go get this block cleaned up!

[Arrow]

OK guys and gals, I have a rather important question for you...

I am going to take my block into the machine shop to have it acid washed to clean it up real good. Here is my question:

Will any damage come from having it acid washed with these two elements on the block? I have no idea how I could remove them. They are in the oil passage lines the first is a ball with a spring behind it and it's located at the oil filter. The second is located above the filter against the head.

[Arrow]

So, it's been a while since I updated this build... I picked up the block from the machine shop this past weekend and have started to get everything ready to be reassembled. I also now have all of the gaskets, bearings, and such to have a good'ol time!

Right now I am painting the block and will then hone the cylinder walls myself - they don't need much, just to break the glaze and give the new rings the ability to bite into something and seat themselves.

Now I have a question for you any of you that know the answer...

I have thought about removing the emissions crap while I am doing the rebuild. I know that many people do this, however, it seems like many (if not all) also have a modified ECU or piggyback for other reasons (like turbo, or an extreme n/a build).

My question is this:If I was to remove the emissions equipment would I also need to tune it out of the ECU so that it doesn't run in closed loop and hinder performance by running richer and not really taking into account some sensors that monitor A/F ratio?

I am planning on keeping the necessities "visible" (EGR and AIV mainly) just not have them functional so that I can clean up the engine bay. However, if this proves to create more problems than it's worth, I will probably just scrap the plan and just keep everything on and functional.

Thanks to those keeping up with my progress!

[Arrow]

Alright guys, I'm in need of some serious help...

I have been working on putting everything back together (mostly getting the crank in) and I ran into a serious issue.

I torqued in all of the mains to 30 ft/lbs (full torque is 45-52) and I was going to spin the crank just to make sure that everything was moving smoothly. Note: I have not installed the pistons yet - just the crank. When I went to spin the crank it would not rotate. Now when I took everything apart the crank would spin smoothly with the old bearings in it and everything. However, now it would not spin anywhere close to "freely" - I had to put over 100 ft/lbs to get it to move.

So, please help me out. I ordered what I thought were standard main bearings from Advance Auto - I told them standard and the part number on the box indicates that it isn't oversized.

For reference the part is Sealed Power MFG# 7285M

It seems like the only reason the crank would resist this much would be if the bearings were oversized.

Any help with this issue is greatly appreciated!

[Gabes13]

how much did all the machining work cost?

sorry I have no answers for your questions though

[Arrow]

Well, the only machining that I really had done was getting the flywheel resurfaced since it was covered in rust. And that was only like $30.

I had the block at the machine shop to have it acid washed and that cost only $45 or so. If I was to be doing a build with new internals and getting it ready to be turbo charged or something, then I would have had more machining done - but I can't justify it right now lol.

[Arrow]

Does anybody know if Nissan would put in 0.50mm UNDERSIZED bearings in from the factory?

I ask because I just measured the bearing diameter (installed and tightened) and compared it to the crank journal diameter and had the following measurements:

Main Bearing = 59.62 mmCrank Journal = 60.1 mm

Going by this in order to get a clearance of .020mm - .046mm (factory spec) I would have to purchase .50mm undersized (or thinner than standard) bearings. That is if in fact I received the properly sized bearings in the first place - which I am unable to find out anyway of telling besides the packaging which has no indication of being oversized or under (and I ordered standard)