Engine ran w/o oil and stalled out...what now?

[drcustom]

A buddy of mind had a very bad oil leak, which we think got low enough to blow the turbo, which we think went and pissed the rest of the oil into the exhaust. However it happened, it took 3.5 quarts of oil to fill it up. The Oil was fine the day before this.

Car was running great, then started knocking, and stalled out at a redlight. Car was towed to the house where we found there wasn't any oil in it. Filled it up with oil for a potential buyer, and it runs fine (haven't really drove it, but engine runs). I think I might be able to hear a light knock (hard to say for sure, there's a pretty good exhaust leak). I can't imagine they got away with this one completely.

So what's the next step? Is it worth crossing fingers and trying to drive at all? With it stalling I have a very hard time believing they could get away with this one, and I'm thinking driving could just push polluted oil through the motor (if it hasn't already). I'm thinkng the first thing to go would have been rod bearings, so start there and see how bad those are? I doubt it could be that easy, but I'm trying to figure out worst case, best case, and most likely scenarios.

[Cloud]

Well... if it is making a knocking sound then you pretty much have to change the rod bearings or you will probably toss a rod and destroy the whole thing. The rest of the bearings are probably junk as well but they are quite a bit less critical unless they are just absolutely destroyed. I ran like 0 oil pressure twice on my setup due to faulty oil cooler lines, up to 30 seconds each time. I replaced the rod bearings only and the knocking went away and I have been running on main bearings that look pretty bad for several thousand miles and beating the crap out of it without issue. Chances are good if it got run without oil for an extended period the cylinder walls and rings are pretty much garbage too though.. but that will just make your compression suck, it should still run just fine but make less power and get lots of blowby.

[D Walker]

Just changing rod bearings might work, but chances are high the rods are oval and you will have rod knock again soon.

[Cloud]

Chances are high? I wouldn't necessarily say that unless it was driven a pretty good amount with it knocking. It's a possibility but I have REALLY done some nasty things to the 1g rods before and they never did anything like that. Just make sure you check the rods for normal specs before you reassemble. Also just to be fair to whoever buys it I would go out and thrash on it a bit when you piece it together and make sure it's at least reasonably solid and that you didn't miss something.

[JackM]

One way to really know for sure is to measure all of the rod journals. Don't eyeball it! The crank could be .010" out and you won't even see it. Borrow or buy the right tools to measure that, and it will give you a good idea what can be saved. Also, look at the big end of the rod for blueing. If it looks dark it's is not going to work.

Jack

[drcustom]

Thanks for all the input. We're going to take it apart this week and see what we can see. If somehow the bearings look really good we probably will just replace the bearings and see what happens in a few thousand miles...if it's questionable we'll measure.

The idea is definitely not to slap something together and let some sucker deal with it...at the least the car will be sold with full disclosure, I think whether or not to sell (whether or not it's going to take a lot of work to fix) is the big question.

I'll post an update letting everyone know how things go.

[Mr. Moose]

Also, look at the big end of the rod for blueing. If it looks dark it's is not going to work.

I thought that for a long time, but I talked with Don Pauter (Pauter Rods owner) and he said that, at least for forged rods, they can take some heat and blueing and not be damaged...

I'd be interested in any other points of view with some backup data on this issue.

[JackM]

Cool, I have some Eagle rods that are a little blue that I'll sell to you if interested.

Jack

[bringit]

Thanks for all the input. We're going to take it apart this week and see what we can see. If somehow the bearings look really good we probably will just replace the bearings and see what happens in a few thousand miles...if it's questionable we'll measure.

The idea is definitely not to slap something together and let some sucker deal with it...at the least the car will be sold with full disclosure, I think whether or not to sell (whether or not it's going to take a lot of work to fix) is the big question.

I'll post an update letting everyone know how things go.

What was the outcome?

[drcustom]

What was the outcome?

The car hasn't been touched as far as I know. I'll post when/if they dig into it.

[drcustom]

I had a chance to take a very quick look at the engine yesterday. They said the car was driven about 100 yards with the knock...

#1 rod has decent blueing, and no bearing at all (at least not on the rod). I think the rod nuts may have been loose which helped to get things started, and the oil issue just made things happen very fast (I should have removed by hand but used an air driver that I don't believe was capable of taking them off without fighting back).

The first rod I pulled was #2, and the bearing looked pretty good - not great but no major damage.

It's not at all what I expected to see, I need to take more time with it. I get the idea that this bearing couldn't have gone that fast - then again with oil and no bearing the car didn't knock - I didn't even have a chance to check, but I'm guessing it spun and most of that bearing will be still on the crank (but I wonder where the bearing material we found in the oil pan came from...possibly #4 or #3 rod).

More info coming, but just thought someone might find this much interesting. I'm assuming that the rod/crank/bearings will be replaced and the engine will be good to go.