[TCSGTO]

When replacing valve springs last winter I noticed the number 7 cylinder is getting oil from the head. The plug was oily and looking into the port showed the intake valve head had deposits. The guide felt tight and compression was within 3lbs on all 8 cylinders.

I replaced the seals and pulled the rocker stud and resealed it since there was oil in the bottom of the stud hole in the port. This part of the Eheads are practically submerged in oil when the engine is running.

This didn't fix the problem. As far as performance a recent trip to the track has the engine making as much power as ever, maybe slightly more, and idle and street driving are normal. Next I'm going to pull the valve cover stud and seal it since it breaks into the port. The valve cover gasket was wet around that bolt hole.

Are the rocker studs that hard to seal and should I try that again? Could the guide be loose in the head? Outside of that I'm out of ideas. I'd hate to pull the head if it is just a simple fix I'm missing.

[firechickenman]

Could you pull the intake and pressurize the intake port? With the valve cover off you should be able to see the air bubbling the oil where it's leaking.

[TCSGTO]

Good suggestion, I'll give that a try. Thanks

[meanone]

The number 3 port on my engine has always been a little dark with some deposit on the back of the valve. Couldn't find the problem until this past winter when I was putting my intake back on after lashing the valves on my new build. I had poured oil throughout the heads after lashing and called it a night. The next night I found oil coming through the roof of the port. This may or may not be your issue, but it sounds like it's near the same place that your oil is coming from. There is a parting line in the casting between the head bolt and rocker stud. The oil is coming through there. I'm gonna wait until the next time that I pull the heads off to fix it I guess.

[Bill Meyer]

For you guys with oil issues, what head gasket are you using?

[steve25]

The expedient thing to do is use spray brake cleaner to remove all the oil from that top area and then spread black silicone all over to seal wherever it was leaking off and be done with it!
There is a product on the market call Seal Lock that I have used on heads that have over heated, cracked and needed a valve seat and it stands up to 3000 degrees, but that's overkill for a simple issue like this!

[TCSGTO]

Lots to think about here. Meanone, that sound a lot like my issue. Bill, I'm using Cometic MLS head gaskets. Steve, would the silicone stay in place?

I had an external coolant leak on these heads 6 or 7 years ago and poured some block sealer in the rad and ran it for an hour, drained & filled and the leak stopped and has never come back. I hope this fix is as easy.

[BADDTA]

Clean it and use "Right Stuff"

Brian

[steve25]

Yes it will if all the oil is removed from the area where the silicone will need to go, I use silicone to seal the 1/2" brass tubes I use to line the push Rod holes when porting through that area, but for that location the silicone needs to be the fuel proof type!
You may find it easyer when applying the silicone to place a small section of aluminum foil on the top of the silicone to help pack it down and spread it at the same time. Once set up you can simply tare the excess foil off!