head questions
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head questions
I'm a subbie newbie and I have a question bout my 91ss that i just picked up I was told the turbo was blown I assumed it was because it smoked bad and smelled of oil I pulled the turbo and found water and oil mixing and the Turbo had no shaft play at all so I did a compression test found one cylinder with 0 the rest perfect I haven't pulled the head yet but if i find it cracked can I use a NA head and just change the cam or are they completely different any help would be awesome so I can get my car on the road again
Just a girl loving to her her hands dirty.
91 legacy ss
91 legacy ss
Re: head questions
With 0 compression I don't think you are looking at a cracked head. I am thinking more along the lines of a piston with a hole in it or a severely burned valve. I am not sure if a bad head gasket would give you no compression or not. There are alot more experienced people here that I'm sure will chime in. Do a leakdown test to see where the air is going and that will give you a good idea what the problem is.
Jeff
Jeff
91 Black SS 5spd. Edm lights, wrx gauges in dash, 45 degree airbox, cryoed drilled and slotted brakes. Invidia divorced downpipe with custom stainless exhaust. To be installed, aluminum a-arms, manual belts, awic.
Re: head questions
I figured a burnt valve or something along that line I was watching in the spark plug hole and the cylinder with no compression had no movement in there the cylinder next to it had something moving valve? The only reason I was thinking crack was because of the fluid mixing the car had just had the head gaskets done and heads resurfaced I need to just take the head off and check it out to really know
Just a girl loving to her her hands dirty.
91 legacy ss
91 legacy ss
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Re: head questions
Yeah, you'll have to take it apart to know. I think a burnt valve is most likely. If that's what it is, they're cheap and easy to replace. There is only one head casting for these engines and the cam gear just reverses from left to right. It's pretty clever. Between the N/A and turbo, the cam timing is different and either the intake or exhaust valves are a little smaller on one of them (turbo, I think) and, of course, and the head that goes on the turbo side is tapped for the coolant and oil lines.
Midnight in a Perfect World on Amazon or order anywhere. The first book in a quartet chronicling the rise of a man from angry criminal to philanthropist. Midnight... is a distopic noirish novel featuring 'Duchess', a modified 1990 Subaru Legacy wagon.
Re: head questions
Probably more then one proble I could be wrong but I didn't think a burnt valve would mix my fluids
Just a girl loving to her her hands dirty.
91 legacy ss
91 legacy ss
Re: head questions
Mixing fluids is either headgasket or cracked block or cracked head. Since yours is a '91, does it still have the oil cooler? That could cause mixing maybe if it's cracked/broken.
Were the headgaskets replaced because of the mixing? Also, you've obviously got oil and/or water getting into the combustion chamber somehow if it smokes while running too.
Were the headgaskets replaced because of the mixing? Also, you've obviously got oil and/or water getting into the combustion chamber somehow if it smokes while running too.
Re: head questions
I thought he was talking about the oil and coolant mixing in the turbo, which would be possible, to what extent I don't know. There could also be some valves that have seized in the open position in that bad cyl.
Jeff
Jeff
91 Black SS 5spd. Edm lights, wrx gauges in dash, 45 degree airbox, cryoed drilled and slotted brakes. Invidia divorced downpipe with custom stainless exhaust. To be installed, aluminum a-arms, manual belts, awic.
Re: head questions
I was told the turbo was bad there was no evidence of blown head gasket no oil in the radiator oil looked clean and smoked black when i pulled the Turbo there was a mixture on the bottom of it only which led me to think driver side head where i found the dead cylinder
Just a girl loving to her her hands dirty.
91 legacy ss
91 legacy ss
Re: head questions
I'm goin to pull the head this weekend and take a look
Just a girl loving to her her hands dirty.
91 legacy ss
91 legacy ss
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- Knowledgeable
- Posts: 9809
- Joined: Mon Jun 16, 2003 11:20 pm
- Location: Beverly, MA
Re: head questions
I thought it already had the head gaskets done. Head gasket failure will very rarely show in the oil or coolant. It tends to go at the fire ring and combustion gases build up in the cooling system, collecting at the water pump cavity until they're enough to cause impeller cavitation and overheating. A cracked head is not common at all, though it sounds like a possibility here. Whatever you do, you'll have to remove the head anyway.
Midnight in a Perfect World on Amazon or order anywhere. The first book in a quartet chronicling the rise of a man from angry criminal to philanthropist. Midnight... is a distopic noirish novel featuring 'Duchess', a modified 1990 Subaru Legacy wagon.
Re: head questions
Sorry if i come across not too smart I am a girl trying to figure this out the head gaskets where done before i got the car but after I saw the mixing in the turbo is when I checked for mixine else where
Just a girl loving to her her hands dirty.
91 legacy ss
91 legacy ss
Re: head questions
Ahh, disregard what I said if the only place you found mixed oil/water was in the turbo.
Re: head questions
Thank-you guys for the info
Just a girl loving to her her hands dirty.
91 legacy ss
91 legacy ss
Re: head questions
Let us know what you find out when you pull the head.
Josh
surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT
If you need to get a hold of me please email me rather then pm
surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT
If you need to get a hold of me please email me rather then pm
Re: head questions
Well pulled the head and gasket and head are perfect no cracks or anything.... what I did find is my number 2 piston is bad prob broken rod damn it. All way worse then i tought.
Just a girl loving to her her hands dirty.
91 legacy ss
91 legacy ss
Re: head questions
Any one wanna buy my 91 ss lol 800 bucks
Just a girl loving to her her hands dirty.
91 legacy ss
91 legacy ss
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- First Gear
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- Location: tigard OR
Re: head questions
i dont want to buy it but i can do the work to fix it cause i have a spare crank rods and pistons from a stock EJ22T
91ss sdn 5spd
taking the time to do it right = stress free fun
taking the time to do it right = stress free fun