More CA problems

[Nismo1182]

Well, the car developed a light knocking noise when crusing under load within the last week or so. In the back of my mind I knew it was something bad but I figured it was probably something stupid easy and not the bad thing.

So Dee was up here and confirmed the bad part. My rod bearings are on their way out. This will be the 3rd time replacing things on this motor. Its been a big headache for me, since the car is my daily driver for work. I hate having it down. I dont know what im going to do next

[Nismo1182]

I guess nobody cares?

Im going to pull the motor this weekend and see how bad the damage is. Hopefully I caught it early enough to replace the rod bearings and be on my way.

Im still waiting for Korey to get back to me so I can buy his downpipe and then my SR turbo is getting rebuilt and it will have a warranty :-)

New clutch is going in also. Then I can have this thing tuned and head to the track to finally get some #'s.

But if none of this works out and I cant find another CA motor, im most definately going to buy an SR then save up for my new car.

[Jezz_s13]

big ends don't normally knock under load, they tend to knock when there is no load on them at around 2-3k.

I had/have an issue with knocking under load and I feel sure it's the small ends I've had them replaced twice now (with non OE bushes) but it keeps coming back, it's not big end shells. I'm waiting for my Pauter rods to arrive, should be any day now.

[NeedCAforS13]

I guess nobody cares?

Im going to pull the motor this weekend and see how bad the damage is. Hopefully I caught it early enough to replace the rod bearings and be on my way.

Im still waiting for Korey to get back to me so I can buy his downpipe and then my SR turbo is getting rebuilt and it will have a warranty :-)

New clutch is going in also. Then I can have this thing tuned and head to the track to finally get some #'s.

But if none of this works out and I cant find another CA motor, im most definately going to buy an SR then save up for my new car.

need any help let me know. I'm in my last week of classes this week, then I have finals, but I'll be on summer break here soon!

what clutch are you using?

Sean

[iliketocrash]

big ends don't normally knock under load, they tend to knock when there is no load on them at around 2-3k.

I had/have an issue with knocking under load and I feel sure it's the small ends I've had them replaced twice now (with non OE bushes) but it keeps coming back, it's not big end shells. I'm waiting for my Pauter rods to arrive, should be any day now.

Is there any way to stop it from coming back? What causes this?

[Jezz_s13]

I suspect mine were down to using crap quality small end bushes, not Nissan ones.As soon as my new rods & piston pins arrive I'll take the lump out and investigate, but I'm pretty sure it's the small ends. I bloody hope so as I've rebuilt it 3 times for the same problem already!!

The rest of the bottom end has been checked, balanced, checked and balanced again, I've even reblocked the bloody thing once with tighter tollerances for the pistons (JE) as I initially thought it was piston slap.

[iliketocrash]

well definitely keep us updated on the bearing prob

[Jezz_s13]

will do, I'll know as soon as the pistons are out. We have asked TopEnd again today when the rods might be ready/sent out, last time we asked they said two weeks, that was two weeks ago so fingers crossed...

[Nismo1182]

I dont hear anything at idle, when I free rev the car I can hear it. When I drive around slowly in low rpms I can hear it. Most of the time I cant because the exhaust is so low it drowns out the noise.

I swear, if I fix this and it comes back, im done with this motor.

[Jezz_s13]

have you checked the journals for ovality?

[boost_boy]

Quote »We have asked TopEnd again today when the rods might be ready/sent out, last time we asked they said two weeks, that was two weeks ago so fingers crossed... [/quote] What's the wait because pauter stock these rods!

Quote »have you checked the journals for ovality?[/quote] He's going to tear it apart this weekend, so I'll guess we'll have to wait.

And Jezz, whomever's doing your machine work could very well be th issue. I find it ironic that you've rebuilt that motor 3 times and can't sort the same problem. On a lighter note, I've never got a DET's bottom end to play "knock-knock who's there"; just melted a few pistons, clean up the bore, stick used slugs and rings in there and keep going. Man, an issue like yours makes me go , hmmmm .

Dee

[Jezz_s13]

Pauter had ran out, they are running a batch off now , there has been a pretty long wait 12 weeks for some people (me 6 weeks), other people have ordered them also (not all through top end).

RE the bushes, well when they have been coming back to me they seem pretty damn perfect TBH, I don't have any problems with the engineers,they have done a fair bit of work in the past for me and really seem to know what they are doing.The thing is the engine goes together fine and is initially fine then the day comes 2k down the line when it gets a proper serious thrash and the knocking re-appears.

one time i rebuild it but didn't change the small ends but had loads of othe work done, rods polished/peened.lightened, crank hardened/knifedged etc, replace all the shells and it jsut knocked as soon as I started it. Took it to bits again, reblocked it but got the small ends done too and it went togther well.

The last thing to change is the actual rod, I want some steelies anyway as my goals have changed (again LOL) I feel sure it's the small ends. it might be that the small end bore has ovaled slightly, they ream the bushes but they spread to fill the ovality at high rev/loads. Just guessing now.

I will soon find out I guess.

It's being RR'd on sunday, hope it doesn't die at 7k on the rollers.

[quest]

Nismo1182have u changed your rod bearings before ?when u stand over the motor and free rev it, do you hear a "rattle" at 2500 to 3000 rpm ?Who is doing turbo rebuilt and cost ? a brand new t28 may be the way

Jezz_s13small end is not a common prob tho, is it ? these are stock pistons ?I've heard 2 neighbours motors with JE pistons, noisy rattleWhat do you mean "reblock"You must have _alot_ of patience

[boost_boy]

Quote »It's being RR'd on sunday, hope it doesn't die at 7k on the rollers.[/quote] So you're going to put it on the dyno while it's having drama? I wouldn't do it! Hell, i would even start looking at the block or maybe (like you said) you have some rod issues.

Quote »when u stand over the motor and free rev it, do you hear a "rattle" at 2500 to 3000 rpm ?[/quote] I've personally listened to it and driven the car this past weekend and it's definitely the rod bearings. i think if he changes them he may be alright because it's not a deep knock, but just a rattle.

Dee

[Nismo1182]

Quest, Diesel Specialties is doing my rebuild (SR T25) for 250 bucks. It even includes a warranty. I cant buy another used turbo and have it mess up on my again. I have quite a collection going on in my garage.

[Jezz_s13]

Dee:Yeah it's going on te rollers, I still drive it hard and it's not died yet.

Quest:No small ends are not a common problem no, I had a set of stock rod small ends checked with my new pins and they were definately worn (120k miles) so I had them replaced. Not With Nissan bushes though.I'm using JE pistons, yes they do slap a bit when cold but they soon shut up once up to temp.By reblock I mean I got another block and bored it out and decked it and rebuilt the engine. The reason for this is that initially I thought it was piston slap so got the block bored a bit tighter, but it's quite obviously not piston slap.

The last time I took it to bits, I examined the small ends again (as I initially never suspected them) and there was visible slop in them. The crank is straight and true.

Yes, I guess I must have patience. LOL