Thought I was finally in the clear...think again

Flitzr951 · 09-15-2007, 05:48 PM

So I've been having some issues wrapping up my 2 year 951 project, today I went through the MAF/MAFterburner connections and found out that the MAF input/output wires were backwards. I fixed the connections and my car finally seemed to be running properly. I was tuning with the MAFterbuner software (while the car was idling) when all of the sudden I lost oil pressure. I immediately turned off the engine and about 2 seconds after I turned it off there was smoke billowing out of the back of the engine and I could hear liquid basically pouring out of somewhere. I looked under the car and oil was in fact pouring out of the back of the engine. So I'm not sure what has happened. My only guess is that the main seal back there popped out, I can't think of any other possibilties so I'm hoping someone else will either have some other ideas or confirm my theory. I'm pretty sure my engine is okay, I was only at idle and it was turned off before it got horrible.

ae1969 · 09-16-2007, 02:14 PM

Rear main or possibly completely blew out the oil pan gasket....

Did you have any issues with either when installing?

Flitzr951 · 09-17-2007, 09:45 AM

I did't have any issues with either of those, but I have a new theory...I beleive what happened was that the plug/cap at the rear of the oil galley was pushed out. I'll be working on getting the engine out over the next few days but that seems to make more sense in that I lost oil pressure instantly along with over a quart of oil. I wouldn't think bad seal/gasket would have such an effect.

2Tight · 09-17-2007, 09:50 AM

Quote:

Originally Posted by Flitzr951

I did't have any issues with either of those, but I have a new theory...I beleive what happened was that the plug/cap at the rear of the oil galley was pushed out. I'll be working on getting the engine out over the next few days but that seems to make more sense in that I lost oil pressure instantly along with over a quart of oil. I wouldn't think bad seal/gasket would have such an effect.

I agree with you about the galley plug. A failed rear seal or oil pan gasket doesn't drop oil pressure so it has to be something that see's full pressure like the plug. Good luck with pulling the motor.

Flitzr951 · 09-17-2007, 11:11 AM

I'm going to tap the end of the galley and use a threaded plug with some locktight, does anyone see a problem with that? I'm just mad at myself for not doing it earlier (I had thought about it back when the block was being modified)

Zero10 · 09-17-2007, 09:11 PM

Don't be mad, this would be the first one I've ever heard of. Not exactly a common failure. You should be able to get that far up with an inspection mirror to see the problem.

If it is the plug I would consider an alternate solution, like threading it and using something like an oil drain plug to fill the hole.

Flitzr951 · 09-18-2007, 07:36 AM

I think I would have to use a threaded plug (i.e. a headless bolt with an inset allen) because it needs to be flush with the block. On the other hand, I made the mistake of re-using the original caps (they had been removed when my block was sleeved) and I think that's the major factor. If I order a new one I shouldn't experience this problem again (seeing that it's not a common failure). I feel like the only way to tap the block properly would be disassemble it and have it flushed etc. The chances of having the same problem are so slim it's not worth running the risk of exposing the internals to metal shavings.

2Tight · 09-18-2007, 07:45 AM

Quote:

Originally Posted by Flitzr951

I think I would have to use a threaded plug (i.e. a headless bolt with an inset allen) because it needs to be flush with the block. On the other hand, I made the mistake of re-using the original caps (they had been removed when my block was sleeved) and I think that's the major factor. If I order a new one I shouldn't experience this problem again (seeing that it's not a common failure). I feel like the only way to tap the block properly would be disassemble it and have it flushed etc. The chances of having the same problem are so slim it's not worth running the risk of exposing the internals to metal shavings.

Do you think the plug might have been compromised when your machine shop tanked the block? My fresh engine back from machining is still on my stand being built but you have me wondering now about maybe replacing it while it's easy. Tapping for a plug at this point isn't an option for me and I think the OE plug installed with Loctite 574 would be as good as new.

Flitzr951 · 09-18-2007, 08:10 AM

The plugs are not supposed to be re-used. They are slightly over sized so when you press them into the block they are a tight fit. Once they are removed they are no good. So if yours were removed you just need to make sure you install new ones. No one told me they were a one time use item, that's where it went wrong for me.

Flitzr951 · 09-18-2007, 09:02 PM

So the culprit was definately the galley plug (I found it in my drip pan this afternoon). Problem is, the part is no longer available from Porsche. I was able to measure the size of the hole (25mm) and my local engine guy was able to order the appropriate freeze plug for me. So for archive purposes, if anyone needs this part, PM me.

2Tight · 09-19-2007, 05:30 AM

Quote:

Originally Posted by Flitzr951

So the culprit was definately the galley plug (I found it in my drip pan this afternoon). Problem is, the part is no longer available from Porsche. I was able to measure the size of the hole (25mm) and my local engine guy was able to order the appropriate freeze plug for me. So for archive purposes, if anyone needs this part, PM me.

Good info - PM Sent