LenWoodruff

I have driven my car about 700 miles since the complete rebuild of the engine. I changed the oil around 500 miles.

I notice that it engine was losing oil but couldn't find any leaks.

I pulled the 1, 3 & 6 spark plugs and they look like they are burning oil especially #6.

The build put in .040 Forged Pistons & moly rings.

Does this looks like rings or valve seals? The heads have new bronzewall valve guildes & umbrella seals.



Cylinder #1



Cylinder #3



Cylinder #6

jim2527

There was a thread recently covering this....

Intake bolts installed without sealant?
Valve covers without PCV baffles?
Malfunctioning PCV system?

LenWoodruff

Valve covers are the factory L82 cast aluminum.

PCV Valve rattles when you shake it so it should be ok.

I doubt they made that mistake about the bolts but could be.

How do I find the link?

OMF

I'd get ahold of a leakdown tester and see if your leaking past the rings....#6 looks bad

It could also be sucking oil from a bad intake gasket seal.....you'd have to remove the intake to find out though....do a compression test or peferably a leakdown to see where you are first.

v2racing

I don't always trust umbrella seals. I prefer a good push on seal. The top of the guides need to be machined on stock heads for these seals though.

An intake gasket can slide up and cause this too, as sstocker31 said.

Mike

LenWoodruff

I am taking it to the engine builder tomorrow. I was trying to see if there could be other things besides the rings.

Sounds like there are other things to check. Thanks again for all of the reposnses.

jimvette999

Did you or builder use thread sealant on rocker studs? The Permatex Aviation Form a Gasket (brown goop) works well. They will suck oil from around the threads on a few of the the rocker studs that breach a few of the intake runners (on some heads... AFR). Press in studs probably not an issue.

LenWoodruff

I don't know. Are the holes drilled through?

The car is at the Engine Builders shop now. They are going to run a compression check and change the plugs. I know more Monday.

jimvette999

Some aftermarket heads have intake runners enlarged for flow such that there are instances where the rocker stud threaded holes breach the runner wall. If your heads are stock or close to it, your runners make not have this issue. My AFR 195s' did and I had your issue so I had to remove rocker studs on several locations that were not blind threaded and coat threads with that black goop thread sealant and "bingo", problem solved. I'm just mentioning possibilities to consider besides the ones mentioned by others in case those are dead ends.

LenWoodruff

Thanks for the info. Mine are factory L82 2.02 heads with the screw in studs. I will find out more tomorrow when I talked to the builder to see what he has found.

techinspector1

A mismatch of angles at the bottom of the intake manifold/cylinder intake port interface is often the cause of engine oiling and is nearly impossible to find with a flammable substance being used to find such an opening. When there is a gap at the bottom, oily crankcase vapors are sucked from the crankcase and sucked into the cylinder every time the intake valve opens. Builders should use extreme caution to insure that the intake manifold ports and the cylinder head ports are parallel with each other in both directions, front to back and top to bottom.

cv67

hopefully its just an intake manifold gasket, has to be

What machining was done to the block? See you posted they put new guides in

LenWoodruff

Thanks guys I hope so to.

They did true up the heads which are factory.

The aluminum intake was not touched. It is factory L82 too.

techinspector1

Thing is, if you haven't owned the block, heads and intake since they were produced at the factory, then you have no idea who has whittled on them and at what angle. Just sayin'....

LenWoodruff

I have had the car with this engine since 1981. So I think everything is factory except the few changes I made during that time.

There shouldn't be any surprises.

I rebuilt the engine myself in 1985 using these components.

That is 32 years before this rebuild.

I am hoping it is the gaskets on the intake and not something in the lower end like unseated rings.

LenWoodruff

Got the car back from the engine builder today. He changed the plugs and ran a compression test.

He said all of the cylinders were at 120. He said that was ok because of the low 9.5 to 1 compression.

I am going to drive it a few days then check the plugs.

When I check the plugs I will look at the piston tops with the bore-scope.

PAmotorman

if the guide liners are the split vs the solid type you need positive seal as oil can be sucked down the split in the guide liner. if the intake is sucking in oil the inside of the intake plenum will feel oily.

LenWoodruff

I am not sure what split vs solid is.

The Valve Pushrod Guides are factory 1 piece stamped steel for each Intake/Exhaust.

PAmotorman

here are the split guide liners. http://www.cylinderheadsupply.com/kl...hoCto8QAvD_BwE

LenWoodruff

I am not sure what bronze wall valve guides the machinist put in the head. But he did put in new valve guides.