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Oil on plugs after rebuild.

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Old 08-17-2017, 08:16 PM   #1
LenWoodruff
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Default Oil on plugs after rebuild.

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

Last edited by LenWoodruff; 08-17-2017 at 08:19 PM.
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Old 08-17-2017, 08:34 PM   #2
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There was a thread recently covering this....

Intake bolts installed without sealant?
Valve covers without PCV baffles?
Malfunctioning PCV system?
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Old 08-17-2017, 09:18 PM   #3
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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?

Last edited by LenWoodruff; 08-18-2017 at 08:10 AM.
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Old 08-17-2017, 09:39 PM   #4
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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.
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Old 08-17-2017, 09:47 PM   #5
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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
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Old 08-17-2017, 10:33 PM   #6
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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.
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Old 08-19-2017, 04:58 PM   #7
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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.
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Old 08-19-2017, 09:50 PM   #8
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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.
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Old 08-20-2017, 11:04 AM   #9
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Quote:
Originally Posted by LenWoodruff View Post
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.

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.

Last edited by jimvette999; 08-20-2017 at 11:06 AM.
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Old 08-20-2017, 11:12 AM   #10
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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.

Last edited by LenWoodruff; 08-20-2017 at 11:13 AM.
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Old 08-20-2017, 11:46 AM   #11
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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.

Last edited by techinspector1; 08-20-2017 at 11:48 AM.
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Old 08-20-2017, 01:25 PM   #12
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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

Last edited by cuisinartvette; 08-20-2017 at 01:26 PM.
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Old 08-20-2017, 02:29 PM   #13
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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.
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Old 08-20-2017, 03:41 PM   #14
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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'....
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Old 08-20-2017, 06:13 PM   #15
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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.

Last edited by LenWoodruff; 08-20-2017 at 06:14 PM.
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Old 08-22-2017, 04:15 PM   #16
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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.
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Old 08-22-2017, 09:21 PM   #17
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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.

Last edited by PAmotorman; 08-22-2017 at 09:23 PM.
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Old 08-22-2017, 11:10 PM   #18
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I am not sure what split vs solid is.

The Valve Pushrod Guides are factory 1 piece stamped steel for each Intake/Exhaust.
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Old 08-23-2017, 12:01 AM   #19
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Quote:
Originally Posted by LenWoodruff View Post
I am not sure what split vs solid is.

The Valve Pushrod Guides are factory 1 piece stamped steel for each Intake/Exhaust.
here are the split guide liners. http://www.cylinderheadsupply.com/kl...hoCto8QAvD_BwE

Last edited by PAmotorman; 08-23-2017 at 12:01 AM.
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Old 08-23-2017, 08:34 AM   #20
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I am not sure what bronze wall valve guides the machinist put in the head. But he did put in new valve guides.
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