Makmov

you just cannot account for all the tiniest pieces, and that is what will take out a bearing or something. The bigger pieces just fall to the bottom and will never get through the pump screen.

And I never liked opening a case up unless going all the way.

The other side of the equation always is there was a failure, which often can not ever be pinpointed, so the potential for another similar failure in another hole is a real possiblity.

Personnally, on a patch job it would always be owner beware, no promises, guarentees, or warrenties. If it blows up it blows up.

Laker

+1, it doesn't take much to clog an oil spray hole.

mshobe

Thanks bobaines - I found Chris originally through Rennlist references when I moved here, and I expect straight talk.

I was planning to sell the car this spring or summer _before_ I got all of this news, so all this is doing is eating into my planned sale proceeds. I don't want to ruin the car's long-term potential – it's got just 69K miles, has run very well outside of these top-end calamities, and looks really, really good for its age. I'll keep interested folks here posted with his analysis, which I should get tomorrow. Frankly, I wouldn't mind selling it with a precise prescription from Chris for what needs to be done and discount from market value by that estimate - I suppose a knowledgeable buyer would consider this issue + Chris's available expertise a pretty through and transparent route to a PPI.

I have complete documentation for the work done on the car since acquisition in December '06.

Indycam

I would need to see the piston and cylinder before answering that , if the piston and cylinder got ground up while the piston ring was making its path to freedom ...
If on the other hand the piston and cylinder showed no "problems" , then all the oil was filtered and any tiny parts of the ring should be in the bottom of the case and or in the filter .

Indycam

For a bit of a ring to get to a spray hole , it would have to get past the oil filter , would it not ?

Makmov

Not necessarily.

think of where all the bits have to go through before it would even get to the filter.

Indycam

So tell me the path , in detail , how something gets into a oil squirter without going to the oil filter first ?

Makmov

It would be difficult, just not impossible. I have seen all kinds of blown up and damaged engine with debris in the strangest places. Realistically anything big enough to get stuck in a oil squirter is likely to never going to get past the magnet on the engine drain plug and never even make it to the filter, in this particular situation.

Would I bet my life on no other damage to any other holes, oil system, bearings or engine in general. NO!

Indycam

Lay it out in detail please . How does part of a ring make it to an oil squirter ?
I see no path that does not involve the oil filter . Please give me detailed info how it could happen .

jody stowitts

Under your breath?!?!!??

Makmov

On paper it sure doesn't look like it could be as we all know wierd stuff ends up in wierd places. How do explaine all the garbage that ends up in the bottom of the tank since all the oil goes through the filter before the tank. How it happens I don't know, but it does.

But if you are so sure, put up, guarentee this guy there is no foreign objects in the oil system. Promise him there is no way possible for a foriegn object include a peice of ring will compromise his engine if he just does a patch, and when if fails are ready to pony up there big guy?

what happens when you turn the motor off? who knows where the piece might go with no pressure pushing it along.

Indycam

Now you are just trying to cover up . Lay out how a bit of a ring get to an oil squirter or simple say you do not know of any way . Don't give another non answer answer . Don't evade .

Makmov

Okay no way, absolutely impossible. On paper, correct, but I don't see you guarenteeing that.

Tell the guy to slap a P&C on it and go.

Metal Guru

The oil is pumped out of the sump, passes through the oil filter and then either goes to the cooler or to the oil tank before being returned to the engine.
The big question is what else was found in the oil besides a chunk of ring. If there's a lot of fine aluminum particles, a full teardown would be warranted.

Makmov

I understand the oil flow of a air cooled 911, but according to Indy there is no way anything can get back into the engine because it has to pass the filter first, which I agree, looks fine on paper.

But who in their right mind would guarentee that?

The other question, unless I missed it, did this piece come from: the case or the tank?

There has to be some small ground up cylinder and piston material. No way the ring can get past without significant damage to those other componets, furthermore, at 85% leakdown it's got major issues. Even with only one ring on the piston in good shape it shouldn't leak that much.