Blown headgasket??
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Instructor
Joined: May 2013
Posts: 177
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From: Fairland Oklahoma
Blown headgasket??
Hey all It's been awhile since I've been on here since my '90 383 was at the paint shop but I'm glad to be back!
now on to the bad news
I have been chasing an oil leak for awhile but tonight I changed my alternator and started her up to check everything and it started normal but after a few minutes my idle rpms rose noticeably higher and not too long after smoke poured from the rear of the engine. Now I've always seen a small amount of smoke but this was alot and it even came inside the car. I believe the source is on the passenger side and when I changed my oil a few days ago I noticed my starter is soaked and there are drips rolling down my bell housing. Does this sound like a head gasket? Or rear main seal? Any help is appreciated! I'm about to head out and use a mirror and light to check and I'll get back with what I see. Oh and before I forget is there any certain areas that are most common to check for something like my situation? Once again thanks!
now on to the bad news
I have been chasing an oil leak for awhile but tonight I changed my alternator and started her up to check everything and it started normal but after a few minutes my idle rpms rose noticeably higher and not too long after smoke poured from the rear of the engine. Now I've always seen a small amount of smoke but this was alot and it even came inside the car. I believe the source is on the passenger side and when I changed my oil a few days ago I noticed my starter is soaked and there are drips rolling down my bell housing. Does this sound like a head gasket? Or rear main seal? Any help is appreciated! I'm about to head out and use a mirror and light to check and I'll get back with what I see. Oh and before I forget is there any certain areas that are most common to check for something like my situation? Once again thanks!
Thread Starter
Instructor
Joined: May 2013
Posts: 177
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From: Fairland Oklahoma
Definitely motor oil... I thought oil did run by the head gasket? But then again I have no idea. I caught a drip of oil on the passenger side and it seems to be under the spark plug. I don't mean the oil is coming from the plug but whats further under the spark plug the could leak oil? I seen a bolt but I couldn't see it well enough to see if it was leaking
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Thread Starter
Instructor
Joined: May 2013
Posts: 177
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From: Fairland Oklahoma
There's a blue gasket I noticed on the front of the block that looks wet but that doesn't explain why most of the rear of the engine is oily
Melting Slicks
Joined: Nov 2010
Posts: 2,216
Likes: 113
From: Michigan
If it's not your valve cover I'd say rear of intake gasket, had too replace the one on my 1st tpi car and when changing my dist noticed my C4 is leaking some. I'll be pulling the intake if I ever get my runners and use a good bead of permatex black for the intake ends like many do. Check your pvc, if it's bad could be building too much pressure and blowing out your gaskets.
Small chance it's the headgasket, I've read of mls multi layer head gaskets leaking oil. And oil does pass thru the headgasket, but that's not the exact spot or reason I've herd mls gaskets leak. I herd they sometimes leak at the point of the gasket and more so when your valley is flooded with oil.
Red drainback, Yellow mls leak area (note this is not a mls and it shows the front and not the rear, it's just an example)
Small chance it's the headgasket, I've read of mls multi layer head gaskets leaking oil. And oil does pass thru the headgasket, but that's not the exact spot or reason I've herd mls gaskets leak. I herd they sometimes leak at the point of the gasket and more so when your valley is flooded with oil.
Red drainback, Yellow mls leak area (note this is not a mls and it shows the front and not the rear, it's just an example)
Le Mans Master
Joined: Dec 2006
Posts: 5,139
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From: H-Town Texas
That or the rear seal of the intake manifold, as others have suggested.
Thread Starter
Instructor
Joined: May 2013
Posts: 177
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From: Fairland Oklahoma
Not sure how yours is set up, but on the LTx motors, there's an oil pressure switch/sending unit assmebly on the rear of the engine that has been known to leak. Oil dripping onto exhaust manifolds would explain the smoke.
That or the rear seal of the intake manifold, as others have suggested.
That or the rear seal of the intake manifold, as others have suggested.
Thread Starter
Instructor
Joined: May 2013
Posts: 177
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From: Fairland Oklahoma
After some more digging I noticed my oil flute is loose and will just come right out. Cold start I have close to if not 80 psi and 60 after warming and it's pegs when I rev it. So with this much pressure I would imagine oil is spraying all over down there. Makes me wonder though, why is my pressure so high?
Thread Starter
Instructor
Joined: May 2013
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From: Fairland Oklahoma
Good to know. Guess I'm just not used to the high pressure. I found a house that goes to my throttle body from the vac system and it was unplugged. Also there's a hose the goes from the passenger valve cover to the throttle body and it has oil inside of the hose. What are these hoses?