Oil leak by Exhaust Manifold

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rodo
Posts: 364
Joined: Sat Dec 27, 2014 5:50 pm
Your car is a: 1981 Spider

Oil leak by Exhaust Manifold

Post by rodo »

1982 Turbo nearly ready to go and now have a new oil leak. Issue is where. Af first I thought it the head gasket, the front right corner, but that seems unlikely. Then I wondered if I sealed up the new studs enough when installing them. Tried to see with a small mirror and it didn't SEEM to be them. Dizzy just back from rebuild and, yes, new gasket between it and block.

Got the heat shield off to have a look: can't see oil by the fourth stud. Oil seems to gather between block and head. I was able to just barely get a finger on that part near the front of the engine and yes, oil. Hmm, so...I've replaced both cam seals and the crank seal. Unless I totally screwed those up, what does that leave?

Anyone ever had a head gasket with enough of an oil leak that you can see fresh oil down the block?

Hopefully I'll get to remove, for the second or third time, all the parts I've installed before.

I love my FIAT, I love my FIAT, I love my FIAT...
18Fiatsandcounting
Posts: 3798
Joined: Fri Mar 15, 2019 11:23 pm
Your car is a: 1969 and 1971 124 spiders
Location: San Francisco Bay Area

Re: Oil leak by Exhaust Manifold

Post by 18Fiatsandcounting »

rodo wrote:I've replaced both cam seals and the crank seal. Unless I totally screwed those up, what does that leave?
Oil from leaks rarely moves upwards or towards the front of the engine. In other words, the source of the leak is usually above and to the front of where you see the oil. There can be some oil creepage along seams, though.

How about the top two studs (or bolts) of your exhaust manifold? These would be #2 and #4, and they're a common source of leaks as the rear of the threads is open to the oil return passageway in the head. Use thread sealant to stop the leak.

-Bryan
rodo
Posts: 364
Joined: Sat Dec 27, 2014 5:50 pm
Your car is a: 1981 Spider

Re: Oil leak by Exhaust Manifold

Post by rodo »

Thanks, Bryan. I checked the studs first thing and not a drop anywhere near them. Looked again at the front and nothing is below either cam seal (and the crank seal is too low) so that leaves, what, galley plugs? Oh, and checked again the cam covers and they are dry all around.

It really is starting to look like the head gasket but I've never heard of one leaking oil like this. Unless I've a terribly cracked head, I guess.
(I mean the one the car. Already know how cracked my own head is.)
18Fiatsandcounting
Posts: 3798
Joined: Fri Mar 15, 2019 11:23 pm
Your car is a: 1969 and 1971 124 spiders
Location: San Francisco Bay Area

Re: Oil leak by Exhaust Manifold

Post by 18Fiatsandcounting »

rodo wrote:Unless I've a terribly cracked head, I guess.
(I mean the one the car. Already know how cracked my own head is.)
Rodo, you're crackin' me up! Errr, so to speak...

I guess an oil galley plug could leak, but that's pretty rare unless they've been removed and weren't properly reinserted/tightened/sealed. I'm also unfamiliar with the turbo setup, so does it have an oil line for the turbo bearings?

How much of an oil leak are we talking about? Just a bit moist, or enough to start a puddle under the car? Any signs that the engine is burning oil?

It's possible that it's a head gasket, especially if the metal rings around the 6 oil pressure lines from the block to the head got damaged, or the gasket were defective somehow. The oil return passageways are not pressurized, so it would be unlikely that they would leak.

If it were me, I'd do a compression check on all 4 cylinders and see if something looks amiss. You should see 140 to 150 psi on each cylinder, and they should be consistent. 120 psi is marginal, and anything less than that is suspicious (or the engine needs a rebuild).

One final thought: Have you checked the torque on your head bolts? I seem to recall that they are higher for the turbo engines.

OK, that's enough questions from me.

-Bryan
rodo
Posts: 364
Joined: Sat Dec 27, 2014 5:50 pm
Your car is a: 1981 Spider

Re: Oil leak by Exhaust Manifold

Post by rodo »

Well, it was enough of a dang leak that I could clearly see a shiny smear after a five minute drive around the block. Too big to just monitor and not worry for a while. Pulled off the timing belt cover (love that job!) and nothing. From what I can see it sure appears to be the head gasket. So weird, but car did sit for years and years. Whew. For sure, will do a leak down test first. That should confirm it.
18Fiatsandcounting
Posts: 3798
Joined: Fri Mar 15, 2019 11:23 pm
Your car is a: 1969 and 1971 124 spiders
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Re: Oil leak by Exhaust Manifold

Post by 18Fiatsandcounting »

rodo wrote:From what I can see it sure appears to be the head gasket. So weird, but car did sit for years and years.
That is weird. I know this doesn't solve your leak, but I rebuilt the transmission in my spider about 2 years ago (dropped the transmission; didn't touch the engine), and upon first startup, a 6" pool of oil rapidly formed under the engine oil pan, dripping somewhere from the exhaust side near the head gasket. Engine oil, not transmission oil. The even weirder thing was that it stopped as quickly as it appeared. I never did figure out what the issue was, but it's been leak free ever since. Kind of like it burped a quarter cup of oil, and that was the end of it...

-Bryan
rodo
Posts: 364
Joined: Sat Dec 27, 2014 5:50 pm
Your car is a: 1981 Spider

Re: Oil leak by Exhaust Manifold

Post by rodo »

Yep, perfect compression. From underneath the dribble of oil is only from the level of the head/block connection. Head gasket. Fun times ahead.
18Fiatsandcounting
Posts: 3798
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Re: Oil leak by Exhaust Manifold

Post by 18Fiatsandcounting »

Before you pull the head, make sure your head bolts are all torqued to spec. If you haven't already.

-Bryan
Nut124
Posts: 748
Joined: Wed Oct 25, 2017 6:39 pm
Your car is a: 1978 124 Spider 1800

Re: Oil leak by Exhaust Manifold

Post by Nut124 »

Is this a head gasket you recently installed?

If so, then something may have gone wrong with the installation. I would not re-install w/o figuring out what the problem was/is.

Are you using head studs or bolts? Was the head resurfaced?
rodo
Posts: 364
Joined: Sat Dec 27, 2014 5:50 pm
Your car is a: 1981 Spider

Re: Oil leak by Exhaust Manifold

Post by rodo »

No, original head/block togetherness.

I'm still not utterly persuaded it is the head gasket, just seems too weird and unlikely. So, with help from a friend, we have come up with Plan B: I'm going to put the hoses and intake back together, get it ready for drivability. Then I will scrub the heck out of where the oil schmear is located, clean it all up real nice like. Then drive it a bit more and see if it gives me a few more clues as from whence the oils may be oozing.
rodo
Posts: 364
Joined: Sat Dec 27, 2014 5:50 pm
Your car is a: 1981 Spider

Re: Oil leak by Exhaust Manifold

Post by rodo »

Buttoned it up, cleaned it up, drove it for ten minutes: oil oozing down the block from right at the head joint. I guess that settles it. Good times ahead. (See? Good times A Head? Kind of a pun...yeah, well.)
18Fiatsandcounting
Posts: 3798
Joined: Fri Mar 15, 2019 11:23 pm
Your car is a: 1969 and 1971 124 spiders
Location: San Francisco Bay Area

Re: Oil leak by Exhaust Manifold

Post by 18Fiatsandcounting »

rodo wrote:Good times ahead. (See? Good times A Head? Kind of a pun...yeah, well.)
I see what you did there. Reminds me of one of the classic lines of the British actor/comedian Benny Hill: "What's that in the road...ahead?" as in "What's that in the road? A head?".

Well, your diagnosis would seem to suggest the leak is at the block/head interface. Weird, but it has happened. Let us know what you find.

-Bryan
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