Ok so I have the dreaded rod knock....now what?

[DJ Cool Breeze]

I found rod bearings for $40...so that covers the parts atleast..the knock is very faint and i think the crank my still be ok. I had to put a screw driver to the oil pan to even make sure that it was comming from the block. I have a couple questions for you guys

1) can I replace the bearings with the motor still in my car? I have no engine hoist, and money is extreamly tight..i mean real tight.

2) is this something i can actually do? Or do i really need a shop to do this...I know about cars and all but i have never actually messed around with the block.

3) How hard is it to replace the bearings once i get the oil pan off?

4) Do i need any specail tools?

Thanks guys,Dan

[slow s13]

I would look throught the fsm and see what your up against, I think youl realize pretty quick that the engine needs to come out, I mean you gota take the front cover off, trans off, both oil pans off just to have access to everything, and you cant just order new bearing and slap em in things have to be measured and certain bearings ordered from the dealer or get the parts machined to accept universal bearings to do it correctly.

youl need at least a decent tourque wrench and probly some micrometers to get the correct bearings in there.

[Geno750]

If you have rod knock, the motor has to be removed from the car, and more or less, you need to completely take the engine apart. The bearings themselves should look silver, to a dull gray.

A bad rod bearing looks like this, and rod knock caused from a bad rod bearing is heard because the bearing has worn down to the point that the rod is actually smacking against the crankshaft, grinding the bearing, and the crankshaft down. For that reason, you should also take the crank to a machine shop and have them inspect it to make sure that it is still usable.



This is the thickness difference of a healthy bearing next to a spun one.



Those are pictures of some of the bearings that came out of my 2003 GSX-R 750 last year, I did the entire rebuild myself and before that I have never touched the inside of a bike motor before. It is doable, the special tools required are some plastic gauge and a very good torque wrench. BTW, my bike Dyno'd 128hp to the rear wheel, so I'd say I did ok on the rebuild.

Also, when you have a bearing come apart, you should hot tank the block and the head as there are now little bits of bearing floating around in the motor
Modified by Geno750 at 1:00 PM 12/30/2006

[DJ Cool Breeze]

would i be better off just getting a new bottom end? I mean this seems like kinda a pain in the *** to have to deal with the berings, then go try and fix the crank as well...god damn it im so mad/sad/dissapointed..

.I have no idea what im going to do now..Me and my girl friend both use this as our only car and she is starting her new job next week...and she has to take a 2 hour round trip to work and back for her first week.

[Geno750]

would i be better off just getting a new bottom end? I mean this seems like kinda a pain in the *** to have to deal with the berings, then go try and fix the crank as well...god damn it im so mad/sad/dissapointed..

.I have no idea what im going to do now..Me and my girl friend both use this as our only car and she is starting her new job next week...and she has to take a 2 hour round trip to work and back for her first week.

I asked myself that many, many times when I was faced with fixing my motorcycle. In the end, I settled on rebuilding it because when I finished, I'd have a blueprinted bottom end vs potentially buying someone else's headache. It was still expensive, I had to buy a new crankshaft, two new rods, a lot of bearings, a head gasket, and had to have the block and top end hot tanked.

I kinda know what it feels like to be in your position, and your second problem is why it is never a good idea to make the DD a project car without a backup.

Just remember you still haven't found the source of the noise, and if you caught it early, you shouldn't have to replace very much.

[sr20-thoj]

just take it apart and fix it yourself.. its not that difficult.. just look at the fsm.. torque everything back to spec.. and youll be fine.. but yeah.. you do need to take the motor out.. might also need an engine stand also.. itll be alot easier..

[ILikeMy240sx]

uh oh. Did you pull your oil pan off? I know that I led you into thinking that its a rod knock but please pull your oil pan off to make sure. Usually spun bearings cause bronzish material to form in your oil pan.

Anyways, if you need to rebuild your engine, you NEED to pull it out of your engine. With the engine still in the car, its impossible to drop the upper oil pan off without removing the entire subframe. Besides, even if you do remove the entire subframe, rebuilding your engine on your back sucks balls. You need to pull it out of the car and then rebuild it completely including all the gaskets and start fresh.

Rebuilding your engine is definitely not hard at all. Ive done 3 SR rebuilds and its not hard. All you need is a proper torque wrench and an angle gauge for those torque to yield bolts.

So, if you decide to rebuild it (which I think you should) rent an engine hoist and get it out of your bay. Also, whats the point of getting another bottom end? Either way, you pull your engine out so why not rebuild it and start fresh?

Let menow if you need help. You can contact me through email.

[efrain240sx]

for the torquing would a 3/8 torque wrench cut it or would I need a 1/2 inch torque wrench?

[DJ Cool Breeze]

Thanks, I really appreciate your help. Im going to need it!!! Im still kinda going through the "shock phase" of it all. I still cant believe my motor is toast after a week and a half.....

I dont need to pull the oil pan to know its rod knock.....I noticed less power in the higher rpm's along with the noise...and I put a screw driver to the oil pan and heard a little noise....so my bet is on me having a busted motor

Whats wierd is after my first oil change (changed from regular t synthetic) My timing chain all of a sudden started hitting the guide...then i hear the ticking like 2 days latter....Kinda wierd......

is rod bearing failure high in turbo sr's???? I went on a web site about the NA sr20de and everyone and thier mother had rod knock, not once with thier motor but multiple times...If this really is prone prblem as i believe it may be....I mean didnt you even have 2 sr20's with bearing problems?...

Anyways Thanks for all the advice and help

[ILikeMy240sx]

for the rod bolts, you need a torque wrench capable of something really small I think it was 11 ft lbs. I think that was the smallest torque setting in the bottom end. The rest is not too much and you do need an angle gauge.

SRs are so tight in tolerance that any starvation in oil will cause various issues such as spun bearings, scorched valve train, etc. If your timing chain started hitting the guide then that means your tensioner was not getting enough oil pressure because the tensioner is operated by oil pressure. The fact that your timing chain started rattling than ticking... sounds like you do have an oiling issue. Perhaps your oil pump is gone. Do you have dents on your oil pan?

Anyways, front cover is a good thing to replace when you do your rebuild since it is 10000000000000000000000x easier to replace the front cover with the motor out of the car.

Next time get an oil pressure gauge. Ive went through so many oiling issues with my car that an oil pressure gauge is almost a must for me.

[DJ Cool Breeze]

wow man you are full of info

Should I even bother to put a oil pressure gauge in there now? atleast maybe it would help me find were the sorce of my problems are comming from..its funny you mention the oil pump, thats kinda what i was thinking.

You have been vey helpfull!!!!!!!!!

[BaliLover]

Oil pressure won't necessarily help as I just spun a rod bearing in my SR and the gauge showed perfectly normal oil pressure, despite the fact that I had a heavier oil leak than I thought and only had about a qt of oil left in the motor. I'm still not quite sure how you can have normal oil pressure and still have an oil starvation issue but ce la vie.

[ILikeMy240sx]

if you install one now, its not like you wont be able to use it later.

Might give you a better idea.

[Blown240sx]

The SRs knock with just low oil levels also. Case in point my buddies Turbo seals were completely gone and over about 2 weeks he burnt up 3 quarts of oil. One night we started it not thinking anything about checking the oil since it didnt smoke that much. I heard it start to knock. We immediatly turned the motor off add oil and it didnt knock after that, until the local oil change place left the oil filter loose dumped all the oil on the road and spin a bearing. Main reason I do all my oil changes.

[efrain240sx]

The SRs knock with just low oil levels also. Case in point my buddies Turbo seals were completely gone and over about 2 weeks he burnt up 3 quarts of oil. One night we started it not thinking anything about checking the oil since it didnt smoke that much. I heard it start to knock. We immediatly turned the motor off add oil and it didnt knock after that, until the local oil change place left the oil filter loose dumped all the oil on the road and spin a bearing. Main reason I do all my oil changes.

my front main engine seal is gone and its leaking oil but I always make sure that oil level is still good. could these be cuaseing my engine knock

[nuts510]

once a bearing starts knocking its already doing damage, at minimum the rods get out around and the crank is missing metal and is now undersized. It might be worth going ahead and pulling the motor and see how much damage has been done.but there is gotta be no cheap repairs and fixing this problem correctly.

[corey240]

i had a bad one and made a thread with pics of the damage of mine. your gona have to remove the motor and tear it done completely. take the crank to a shop and get it ground to the next size down and then get a thicker bearing. possibly may need to replace the rod. i would replace the rod,get thicker bearings and get the crank milled and youl be good to go.

[DJ Cool Breeze]

If i were to buy an sr block......That would be the whole bottom end right.....crank/rods right??? I found a good deal on a block and wanted to know if thats what is included in a "sr block"

.....I have come to the conclusion I am jsut going to get the car up and running then sell it. so im trying to go the cheep way..if i can to not take so much of a hit when i do sell this car.

What do you think i could get for my car?

92 black top hatch, stock everything----blow off valve/intercooler/turbo. redone interior, New turbo manifold, new walbro fuel pump, new 3 inch turbo back exhaust,dvd player.......body is great with a small dent on drivers side

[corey240]

i dont know ho wmuch you could get for the car but, when they say an sr "block" they probly mean literaly the engine block, nothing mroe,nothing less. you beter ask them specificaly what comes with it if its the block or a "long block" with the crank and all the good stuff.

[Poor_S13_Driver]

Sucks to hear man. But i have a question. Did you inspect your oil pan before installing the SR? Ive always hear of dented oil pans causing this exact issue. And i was curious if you checked this out before you started swapping.