Blew another engine.

[Icecream]

Update post 29, some unexpected news...rod bearings show no copper, thinking a main bearing went.



Started knocking when I drove home today. Believe to have seen flakes in housing.

[cudzich09]

sorry that's unfortunate! Good luck
Specs?

[02_lsb]

Was this a rebuilt engine?

[Icecream]

It was a mystery engine I bought. Looked healthy, did the bearings and vanos and drove it for 20k.

Has 230k on it.
Subframe done
Bilstein b12 and all bushings
Avin avant 3
Stock.

[sapote]

It was a mystery engine I bought. Looked healthy, did the bearings and vanos and drove it for 20k.

Sorry on the bad news. Who installed the rod bearings and what is the spec? Crank journals were on good condition at the time?

[Icecream]

Sorry on the bad news. Who installed the rod bearings and what is the spec? Crank journals were on good condition at the time?

Yeah, all good. I did the bearings, they are standard ACL and I am meticulous though I did not plastiguage it, probably should have.

So the last couple days I did some redline shifts and noticed when the clutch went in, the RPM's would surge (felt like it would go past redline) and then drop. It crossed my mind that this was bad. Imagine redlining the engine and clutch in, letting the RPM spike suddenly, then shifting. It is SMG so I don't know why the computers let it do this but it is what it is. Couple that with the fact that it was a mystery engine and well...
I checked the filter a week ago and it was good. Checked today and it was clean after I heard the initial knock. It was more of a tsk tsk tsk sound. Then when I went to start it up again. the knocking went nuts. Going to check the filter again but I am certain it is rod knock. if only I took that 10k offer a week ago...

Checked filter, trace amounts of copper. Tempted to open it up and look at the crank. But i won't lol.

[mtpktz]

Sorry to hear - it's unfortunate how much bad luck you've had with the car.

PMd.

[sapote]

Red line or a little spike over it doesn't mean damaging rod bearing, but it is more about floating valves then bent valves.
"So the last couple days I did some redline shifts and noticed when the clutch went in, the RPM's would surge (felt like it would go past redline) and then drop. It crossed my mind that this was bad. Imagine redlining the engine and clutch in, letting the RPM spike suddenly, then shifting."
Down shifted or up shifted?

I would drop the pan and see what happened. Maybe a rod bolt has come loose. I don't think a seized bearing could get to red line. I hope crank is good,
Yeah, doing plastigauge to have a peace of mind.

[Icecream]

Sorry to hear - it's unfortunate how much bad luck you've had with the car.

PMd.

Tell me about it. I was supposed to pick up an M6 tomorrow but now I'm wondering if I should do this to myself again. This feeling and headache right now is hardly worth all the pleasure I got from the car.....It was running flawless the entire last year. Not even a CEL>

[Icecream]

Red line or a little spike over it doesn't mean damaging rod bearing, but it is more about floating valves then bent valves.
"So the last couple days I did some redline shifts and noticed when the clutch went in, the RPM's would surge (felt like it would go past redline) and then drop. It crossed my mind that this was bad. Imagine redlining the engine and clutch in, letting the RPM spike suddenly, then shifting."
Down shifted or up shifted?

I would drop the pan and see what happened. Maybe a rod bolt has come loose. I don't think a seized bearing could get to red line. I hope crank is good,
Yeah, doing plastigauge to have a peace of mind.

If I had any confidence the crank was not damaged, I would do it. It knocks so I am pretty sure it is gone. If the crank is gone then it is too much work for me to get into right now. I think I messed it up when I started it the second time. I'll see how I feel this weekend.
I just figured the RPM spike suddenly, at 8k, was enough to do damage. Fuck, car was running so strong today, no shit I was driving home and thinking to myself why the car felt so strong and wishing it would always feel so good.

[Syfon]

Checked filter, trace amounts of copper

If there's copper in the oil / filter, a bearing has spun and the corresponding crank journal will be scored.

That means crank out and full rebuild.

Sorry to hear the motor knocks

[jet_dogg]

Well that sucks.

What's the explanation for this?

[Icecream]

Well that sucks.

What's the explanation for this?

No idea other than my theory above. Just insane really, I am still in disbelief that I am dealing with this again in less than two years. All this time and money and I have nothing to show for it but a paper weight. I see new cranks are 2k and I am tempted to rebuild it just so I don't lose so much offloading it not running, but I feel I am digging a deeper hole with that idea.

[FBloggs]

Bummer.
This chassis is so much like the E30M3 imo. Needy.
it is probably the price we pay for a tuned nat asp zinger.
I rarely rev mine up to 6k.
Mostly because it is romantic to chase the tach, just like the s14.
I spun rod bearing #3 on an s14 and the rebuild was of bmw proportions.
I enjoy the car but there is this little spider in the corner of my head whispering about rod bearings.
like you, I bought a car with unknown history, but the engine was so tap free for a solid tappet that I jumped on it.

[Cubieman]

Sorry to hear this, I do envy your ability to rebuild an engine, if mine should ever need doing I fear it may be too much for me but I likely can't afford to have a shop do it either so I'll sink or swim on my own.

That sucks to here you potentially considering being done with this chassis altogether. Do engine swaps trip your trigger? There could be some interesting (and expensive) options to choose from, LS, 2JZ($). But any swap would likely be such a headache that it's not worth going that direction either.