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Discussion Starter #1
Hi guys - after thinking my oil leak was lower than this I found today that it is coming from the upper section of the engine. A bit hard to see here but there is a lot of oil leaking out from here.

It is the most wet/oily on the plane where the engine block and transmission meet. I'm still learning my Alfa engines but does this suggest any specific seal(s) as a likely or common issue?

Thanks for being patient, I asked earlier about this but got the location of the leak wrong.

 

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But Mad North-Northwest
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Valve cover gasket, valve cover half moon seals, or head gasket are most likely candidates. The big hex plug you see there at the back of the head can also leak through the threads.

So lots of opportunities for leakage from the top. I think mine was leaking from all of them at once.
 

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Might be an oil leak from the head gasket. There are pressurized oil passages which have O rings, plus the drain down oil returning from lubricating the cams has several unpressurized returns through the head gasket. Can you get an inspection mirrow and take a look at the rear joint between the cylinder head and rhe rear of the engine block? You might want to quarter wash down the rear of the engine/front of the transmission in order to see any new oil leaking back there after the wash job. Also, you can buy an additive for your engine oil which will show up a leak when searched for with a black light. There is a kit for doing this sold at some Auto Part Stores.
 

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Discussion Starter #4
Thanks guys. Very much appreciate the coaching.

She needs a valve job at this point so seems like I should add resealing all of these to the "now is the time to do this" list right?
 

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But Mad North-Northwest
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Well, yeah, if the head's gotta come off anyway that should take care of all those items.

Beyond replacing all the gaskets, pull off the big hex plugs at the front and rear of the head and give the threads a few turns of teflon tape. Easy to do when you've got the head out and will prevent leaks there.
 

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tdskip,

If you do a valve job, while you have the cylinder head off the engine be sure to stop and research "cylinder head removal and replacement" on this BB for all the tips and tricks to ensure a leak free result when you reinstall the head. There are several tricks which, if ignored, will almost guarantee you will end up with another leaking head gasket on your newly reinstalled cylinder head. Alfa heads and headgaskets are pretty tricky items.
 

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Beyond replacing all the gaskets, pull off the big hex plugs at the front and rear of the head and give the threads a few turns of teflon tape.
I never thought of putting teflon tape on the tapered plugs to prevent oil leaks. It certainly can't hurt. However, I have to say that those plugs haven't caused me any problems; the oil isn't pressurized behind them and by definition, tapered threads are an interference fit.

Replacing the cam cover gasket and "half moon" seals is easy. The oil pools beneath the cams can rise above the bottoms of the "half moons" so they can cause leaks. Installing new "half moons" with a bit of sealant might be worth a try; you don't need to pull the head to replace these parts.

But, the six O rings are the most likely cause of a head-related oil leak. If for no other reason than they are the hardest to access!
 

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Poll: How many of us Alfa owners have leak free spiders?
Mine does not leak very much.:wink2:

Funny thing is, my GTV6 has never leaked and I know that there is oil in it.
 

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But Mad North-Northwest
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I never thought of putting teflon tape on the tapered plugs to prevent oil leaks. It certainly can't hurt. However, I have to say that those plugs haven't caused me any problems; the oil isn't pressurized behind them and by definition, tapered threads are an interference fit.
I got the advice from someone on the board - it works well. The oil isn't pressurized, but the caps seal the cam galleys so oil can seep out through the threads. Made a mess on both the '91 and the Giulia.

Teflon tape is easy and also safer than cranking down on the aluminum threads to try to get them to seal.
 

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In industry tapered threads are almost always sealed with either teflon tape or a liquid sealant.
 

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I never thought of putting teflon tape on the tapered plugs to prevent oil leaks. It certainly can't hurt.
I would NEVER use teflon pipe tape on any threads that may come in contact with gasoline or oil. If you want to seal threads and still be able to remove a bolt or a threaded fitting, Type 3 (Aviation) Permatex is the classic solution.

The only automotive application for teflon pipe tape I have ever heard of is use on brake bleeder threads to prevent air bubbles passing the treads when using a vacuum bleeder. Apparently teflon tape is not affected by brake fluid.
 

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I would NEVER use teflon pipe tape on any threads that may come in contact with gasoline or oil...... Apparently teflon tape is not affected by brake fluid.
I'm no chemist. But I have a sense for what is a "weak" solvent and what is a "strong" one. On that scale, motor oil is pretty weak - it doesn't dissolve much, and I'd be surprised if it attacked teflon. Brake fluid, on the other hand, would probably dissolve kriptonite.

I have heard that teflon tape should not be used on fuel line fittings. Not because gas will dissolve it, but because stray bits of tape might break off and clog the carburetor. Don't know if this is a real concern - I adhere to the "cinch it down tighter until it stops leaking" way of thinking.
 

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I once tried to stop a leak using pipe tape at the compression fitting on the fuel line to an updraft carburetor on one of the cars at the auto museum where I volunteer. It started leaking almost immediately and when our chief mechanic asked what I did, he admonished me not to do any more of what he called "Home Depot fixes", and laughing, added "…or he would put me in his scrapbook."

I took it as gospel from someone I respect but don't know teflon chemistry to be honest. Here are a couple of pictures from his scrapbook. I do not want to be in it, so no Pipe tape for me.
 

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But Mad North-Northwest
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Yeah, teflon is fine from a chemical compatibility standpoint, Richard. People sometimes don't like to use the tape because they're worried about pieces breaking off and clogging something. One could have the same issue with silicone or Permatex, but if you use whatever product sparingly and aren't an idiot that's pretty hard to do in this application.

Permatex is fine too. The stuff I've used in the past is this:

Thread Sealants : Permatex® High Performance Thread Sealant

Which is probably the mass-market version of the aviation stuff. It contains PTFE (teflon).

You generally need to use something on tapered threads to help make them 100% tight. Either of these will work fine, and my engine's a lot less messy since I put on the tape.
 

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I once tried to stop a leak using pipe tape at the compression fitting
That was your mistake. Teflon tape is for tapered threads, NOT compression fittings.

You generally need to use something on tapered threads to help make them 100% tight
+1
 
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