Blew another engine.

[Icecream]

So I think I know what happened. A while back I blew the vanos line. I lost almost all the oil (but do not recall a red oil light and the low level sensor was broken so I never got a yellow lamp) and I was driving in higher RPM's. Have an oil sample sitting on the bench to send to blackstone that I never got around to sending. If I had to bet what caused/started this, I would have to say that was it. I added 4 quarts that night, maybe more. In hind sight dumb of me to not have pulled the bearings immediately to inspect but figured since I never saw the red light and only drove 2 miles it would be ok. Put 6k or 8k on it since that happened and now this.

[Obioban]

Well that sucks.

What's the explanation for this?

My guess would be that likely the crank on the replacement mystery engine wasn't great (e.g. had spun a bearing for the previous owner).

[Icecream]

My guess would be that likely the crank on the replacement mystery engine wasn't great (e.g. had spun a bearing for the previous owner).

possible I suppose, I really think the blown vanos line did it though, I was stupid low on oil. Probably a good idea to have the engine shut off automatically when that red light comes on, easy to miss really. Couldn’t be too hard to rig up. When I did the bearings, none were horrible, crank looked ok. But it was a mystery engine. Probably better off just doing a full rebuild next time. Shit maybe I should rebuild the one sitting in my garage now. If anyone has done a rebuild on spun engine pm me and maybe we can chat about the cost/process a little.

[sapote]

I lost almost all the oil (but do not recall a red oil light and the low level sensor was broken so I never got a yellow lamp) and I was driving in higher RPM's.
I added 4 quarts that night, maybe more.

Agreed, that this is a big factor. Anyone know how to do a simple self test on the oil level sensor? Turning on the key only tests the oil pressure sensor I believe. If I lost 4 qt of oil I am sure the rod bearings should be out to check. Well, it's a fluke accident and we all live and learn, and hopefully the next engine will serve you well for a long miles. You have invested a lot of time, moneys and knowledge in this chassis, so just rebuild the engine and luck will sure come your way this time.

a) when you did the rod bearing, did you have a good look at the crank journals condition? I'm sure you took some careful measurements.
b) Which part of the vanos oil line leaking? Loose or missing 10mm bolt holding it to the block?

[Obioban]

possible I suppose, I really think the blown vanos line did it though, I was stupid low on oil. Probably a good idea to have the engine shut off automatically when that red light comes on, easy to miss really. Couldn’t be too hard to rig up. When I did the bearings, none were horrible, crank looked ok. But it was a mystery engine. Probably better off just doing a full rebuild next time. Shit maybe I should rebuild the one sitting in my garage now. If anyone has done a rebuild on spun engine pm me and maybe we can chat about the cost/process a little.

When I made that post, I didn't see the vanos oil line post, and potentially running the engine without oil. That certainly sounds like a possible cause, as well!

[Icecream]

a) when you did the rod bearing, did you have a good look at the crank journals condition? I'm sure you took some careful measurements.
b) Which part of the vanos oil line leaking? Loose or missing 10mm bolt holding it to the block?

Thanks man.

No self test. On my old sensor I’d get a low oil light regularly even though I had oil and the temp sensor stopped working (same sensor). On this engine I got a low oil light a couple times despite good level and the temp sensor worked fine. It was on my list to change at the next oil change, had a brand new one sitting in the garage and just forgot to swap it when I replaced the motor.. Just really shit luck. I’d just do it at 75k or so. Stupid easy and cheap to replace and a no brained for a part that can kill your motor.

The crank looked great. I didn’t measure them. I really should have but didn’t think I needed too at the time (never even read about plastiguaging a good journal until then). next time I will for certain.

The line sprung a leak near the bottom, near the foil. Bad place because instead of squirting all over the headers and creating an early smoke warning, it just leaked onto the support plate. Only reason I caught it is I pulled into a well lit garage at the grocery store and saw a thick black oil line leading right to a large puddle under my car.

I was seeing red last night but after reassessing losing tons more money on the car, I am feeling better about rebuilding it. Just need to take it to Lang to polish the crank and measured, get it treated if needed, hot tank the block and head and button it up with stock pieces. Figure 2500 and a couple weekends should get me there.

[bigjae46]

I think plastigage is important when installing a used replacement engine...at a minimum. There are probably more engines out there with oversized bearings due to normal wear and tolerances. Also, it is possible that someone will clean up a journal, replace the bearings and send it after spinning a bearing. Not bother to replace the rod end. May or may not catch that with plastigage.

I don't think the blown line would have caused the issue. If the line blew and you had to add 4 qts of oil then how much of the oil leaked out AFTER the car was shut off? Probably quite a bit as pressure bleeds off in the system. You have about 5 seconds once you lose oil pressure to shut the engine off. I know this...unfortunately. As long as you had some oil pressure when the engine shut off then I doubt the oil line rupture caused any damage.

[Icecream]

I think plastigage is important when installing a used replacement engine...at a minimum. There are probably more engines out there with oversized bearings due to normal wear and tolerances. Also, it is possible that someone will clean up a journal, replace the bearings and send it after spinning a bearing. Not bother to replace the rod end. May or may not catch that with plastigage.

I don't think the blown line would have caused the issue. If the line blew and you had to add 4 qts of oil then how much of the oil leaked out AFTER the car was shut off? Probably quite a bit as pressure bleeds off in the system. You have about 5 seconds once you lose oil pressure to shut the engine off. I know this...unfortunately. As long as you had some oil pressure when the engine shut off then I doubt the oil line rupture caused any damage.

Less than a liter at the puddle. that leaves 1.5 maybe in the system, I think it was less and I was having a good time with it but no way to know for certain at this point. I really should have parked it and done the oil analysis right away but being my daily, I just didn't get to it.
One thing that would help me out if anyone knows, is there a way to measure the rod to see if it needs to be replaced? When I spun the first bearing the damage to crank was minor and the bearing rotated about a half inch. Bearing was stuck to the crank but not seized. Asking because if there is any way to check the rod and if it is good, I will rebuild almost for certain (or if I can get away with replacing one rod that would make sense too but from what I read, it is all or none), which adds 1200 to the build, still probably worth it. Not planning to hone or anything if the bores are good either, seems to cause more problems than solve a lot of times.

[bigjae46]

If you spin a bearing and there is rod knock, the rod needs to be replaced. The knock causes the big end to become oval. At a minimum, you'd want to replace the rod and wrist pin. To go through that, its worth it to pull the crank and at least have it checked. You should have the crank measured, repaired (heat treated if grinding), polished. Then measure the rods.

Lang Racing is a good option for a repaired crank. The last time I checked, a new OE crank wasn't totally unreasonable considering the cost to repair a crank.

[Icecream]

If you spin a bearing and there is rod knock, the rod needs to be replaced. The knock causes the big end to become oval. At a minimum, you'd want to replace the rod and wrist pin. To go through that, its worth it to pull the crank and at least have it checked. You should have the crank measured, repaired (heat treated if grinding), polished. Then measure the rods.

Lang Racing is a good option for a repaired crank. The last time I checked, a new OE crank wasn't totally unreasonable considering the cost to repair a crank.

Thanks, that makes sense. Lang actually looked at the crank and they seemed to think I could get away with polishing the crank, reasonable price too. If I can replace one rod (and not worry about balancing and all that for all 6), that would be splendid.

[bigjae46]

You don't have to balance a used OE rod. Actually you have to balance the entire rotating assembly (crank, bearings, rods, pins, rings, and piston).

[sapote]

I don't think the blown line would have caused the issue. If the line blew and you had to add 4 qts of oil then how much of the oil leaked out AFTER the car was shut off? Probably quite a bit as pressure bleeds off in the system. You have about 5 seconds once you lose oil pressure to shut the engine off. I know this...unfortunately. As long as you had some oil pressure when the engine shut off then I doubt the oil line rupture caused any damage.

If the hose blown and no vanos codes, then the hose opening was small and still provided enough oil pressure for vanos system, and the leak is the exact vanos pump rate.
OP, did you find out how big was the hose opening? I think it was like a small crack and not a total opening.

I

[Icecream]

If the hose blown and no vanos codes, then the hose opening was small and still provided enough oil pressure for vanos system, and the leak is the exact vanos pump rate.
OP, did you find out how big was the hose opening? I think it was like a small crack and not a total opening.

I

Yeah, small crack which again made it more difficult to notice something was wrong. No CEL either. I just can't imagine what else would do it. 1 quart or so is just too low to run on. at least a half quart is being pumped through the motor and one tight turn or two and the pump will starve momentarily. Enough to lose pressure for a second, at high RPM and cause a problem. Again, should have done an oil analysis but being I put in over 4 quarts of fresh oil, the results would be meaningless. So I waited for the next change, forgot to get a clean sample and waited for the next change, which was too long .

[Icecream]

Well hello errbody. Finally got to opening this thing up. Pulled motor and started dissasembly (not before sending the bellhouse for machine work, yay ) but look at my photos below. All the bearings look like this and have the same lines going longitudinally around but not worn and no copper showing.

Nothing spun, crank not scored. Everything was tight. Thinking Mains.

[Icecream]

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.

Not done with the chassis, after tons of shopping around and getting the M6, there is no replacing the M3 for under 80k these days. Thats not to say that I don't adore the M6, it's a beast all it's own. Not a swap type of person unless it was s65/s85 and that's just out of the question, and even then, the S54 is such a sweet engine I appreciate more and more everyday I don't think I could ever not have one (unless a gt3 rolled into my life).
We'll see how good my rebuild skills are after it's complete and running like a sewing machine again lol. If yours ever blows there are tons of resources that I'm sure you could tackle it. Taking apart my sec9nd S54, it really is not that complicated at all. Honestly the biggest challenge by far is keeping it clean during reassembly.

Block gets cleaned this week and most of the parts have arrived.

Now more weirdness that I can't put my finger on. Engine was knocking, pulled apart, nothing spun, no copper showing and no direct indication of oil starvation. However, there appeared to be one particle streak in a bearing, did not look critical, no copper. I am suspecting I was sold a bad motor. Mains all looked excellent. So the bad motor theory is sounding more plausible, just my luck.

Not planning to hone if everything looks healthy when I pull the pistons. With good luck I'll have it buttoned up in a couple weeks and can finish the 6spd swap and we will be in business.

Edited: Marks on crank were from the factory nitriding, shop looked at it and said it was fine. polished, magnafluxed.