Just for grins, let's vote on how f'd up my SR is and see who knows their SR20's.

The situation: Rod knocking about 2500-3000rpm. Not really noticeable at idle yet. Started about 1/2 mile from my house while I was out getting food, drove it home. Had/has fresh oil in it, new filter - 2 weeks old. I'm thinking maybe high mileage/old oil pump shitting out caused the issue. Or just ancient bearings. I dunno. No scientific evidence to point to exactly what's wrong with it. Gotta pull the motor out of the car this weekend and see what needs to be replaced. Which doesn't really bother me since I needed to change out the clutch/flywheel and I hate pulling the transmission in the driveway. Haha.

Already ordered new oil pump/cover and oil pickup tube and I will order new bearings once I get it opened up. I'm crossing my fingers that I can just pull out the bad bearings, put fresh ones in with a new pump, and call it a day.

But how fucked do you think it is? And why?

 

If you've only got 1/2 a mile cruising on it like that and it's only at 2500-3000, if it is rod knock it's probably not that bad. Sounds more like a chain slap or piston slap to me. The only rod knocking I've heard was pretty obvious at all rpms under vacuum, including bliping the throttle to 1500 in neutral from idle.

You're going to have the engine mostly apart to do the pump (have to pull the head and pans), so might as well pop a few rod caps and take a peek. If the crank isn't scored, just slap some grade 0's in there and call it a day.

 

I thought I could get the pump off without pulling the head? Just those two front bolts that hold the head to the cover? No? I had planned on pulling the pans and checking out the rod bearings and main bearings.

I have to confess I don't know what chain slap or piston slap sounds like. My CA's had spun bearings before, and I assumed that was what I was hearing. I guess I should get someone who knows a little more to come listen before I pull it apart... Its pretty loud, I mean people could hear me pulling in the driveway from inside the house.

This is almost exactly what it sounds like. And you have to give it a little throttle like they're doing to hear the noise. One of the comment suggests its piston slap too...

http://www.youtube.com/watch?v=uZplzqSbKmo

 

Would a collapsed hydraulic lifter make a noise like that?

 

OK that's definitely rod knock, and the vid is a pretty bad case. Not the worst thing I've seen (a symphony of 4x rod knock is awesome), but I wouldn't expect to reuse that crank (and have it last). Tear it down and have a look. Worst case is the crank is done and you spend an afternoon at LKQ Cophers digging one out of a SER. A full set of bearings at Nissan is $100. Not a lot of money involved, but lots of time.

You can technically change the front cover with the head on, but it's a super duper pain in the ass and you'll probably destroy the front of the gasket and have a major oil leak. Been there, redid that. The problem is that the cover has to be installed parallel to the front of the block because the oil drive collar won't allow you to tilt it. There are also locating pins that interface the cover as well. If you do wind up changing the crank, you can probably make it work, though. With the crank out, slide the cover on the drive gear. Then you can position the combo without a problem. You might have to pull/reinstall the pins on the front of the block, too.

 

If you can hear the rod knock, you need a new crank. You probably need a new rod too, but you can like, check stuff and measure stuff to tell you that further. I wouldn't want to re trust those rod bolts after that though.

and its fucked up b/c it probably got driven on a crushed pickup for a while.

 

Come to think of it, that rod is probably done, too. Now you're going to HAVE to pull the head. Can't reinstall pistons from the bottom. Add HG to the list.

 

[GHETTO]

you can pull the front main seal out. slip the oil drive collar off, and shimmy the front cover out. that helps alot, you just need a new front main seal

[/GHETTO]

 

Damn. That oil pump looks like it was designed to come right off. Thats stupid that it gets all hung up on shit. High five Nissan.

Mine isn't as loud as the video, but it is the same sort of noise. I guess we'll know more once I pull the oil pans and rod/main caps off.

Gay gay gay.

 

damn your pissed. when a motor is rod knocking it is like taking a hammer to the crank and rod. bends the rod and dents the crank. if you try and just replace the oil pump and bearings as soon as you turn over the motor you will ripp the bearings and rod knock again. i say completly rebuild the botoom end with new crank,rods and rings,bearings... it's not cheap but i would rebuild a motor than buy one for 2200 and not know how it was treated. happens enough that people know about it. they buy an sr20 swap it in with bolt ons and then start it and it has rod knock. better off to rebuild it..