My engine is burning crazy amounts of oil. Going to pull the head off soon.

1. What do I look for to determine my valve seals went bad?
2. What do I look for to determine my oil rings went bad?

Thanks,
C

 

I'm not sure how you could diagnose a bad valve seal. To check the ring tolerances, you've got to the pull the pistons, slide the ring into the cylinder and measure the end gap.

Are you sure you're burning this oil and not just losing it from a slow leak? What do the spark plugs look like? Any blue smoke?

There are products out there that will condition old seals and stop some internal leaks, like if you had a bad valve seals. A friend of mine put some Lucas Oil Treatment in his motor and after about 3000 miles, stopped burning oil comletely.

 

No drips/leaks.
Plugs look fine.
Compression ~280, all across.
Leak down says 1%, all across.
Burns at least 3 quarts a week.
Smokes out the back when I 'get on it'. Kinda bluish I guess.

 

To diagnose bad valve seals or valve guides one of the easiest things to do is let it sit and warm up, take it out, beat the snot out of it for a few then park it and turn engine off, give it about 10-15 minutes and start it back up, if it smokes at start-up while idling then the leak is usually up in the head. When this happens basically oil is leaking down through the head and sitting in cylinders, when you start up it burns off right away.

 

If it smokes under full throttle it is typically the rings, if it smokes under deceleration (high vacuum conditions) it is typically the valve guide seals.

 

Well, it definetly smokes alittle after the car sits for awhile. And that last for about 2 minutes. It smokes occasionally when I accelerate hard.

Are there any visiable characteristics to look for, as I will have to remove the head regardless.

Thanks all,
C

 

If you are sitting there for a little while and take off then its the valve seals. The reason for the big puff of smoke after starting the car or just sitting there idling is because the valves are constantly leaking but because its not be pushed hard it is not burning as bad. I dont know if this makes sense to you but most likely it is your valve seals. But they must be pretty bad to burning 3 quarts a week. Good luck fixing it.

 

Are you using a turbo? If so the seals could be worn and oil's leaking into the exhaust. If it passed a compression and leakage test as good as it did, then I don't see how it could be rings/valves. Did you say 280psi compression??

 

this might be a little extreme and quite worksome, but you might wanna check your actual valves themselves, as in take your head off inspecting the underside of your head.

A few years back, a friend of mine had a JDM GSR engine in his EG; he drove on it for quite a while; from memory it smoked from day; we could never figure out why until we took his head off one day. What we found was that 1 and only 1 of the valves (can't remember if it was an intake or exhaust valve) actually had a piece of it missing (like small pie peice cut from the valve's big round foot).....it somehow broke off and was probably like that shipped from Japan too.

so you might wanna check on that if you're up to it...

 

Compression & leakdown tests will not show valve stem seals. The valves themselves are closed, so those tests will show leaking rings or valve seats.

Leaking valve stem seals also leak more under high vacuum, like idling or engine-braking.

 

GSRmatt hit it on the money.





[Modified by GM2000ITR, 6:26 AM 3/26/2003]

 

I think nolimits was questioning the 280psi, kinda high don't ya think?