Oil pooling on exhaust valve.

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doogievlg

doogievlg

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Tonight I finally found some time to get my engine in. I got it back from the builder back in May and it has been sitting in the engine stand. Well I fought with the headers and finally got the engine mount bolts in when I went to bolt the headers up I noticed oil coming from the exhaust port. Stuck my finger in and there was a puddle on the valve. Same thing was happening on both Exhaust valves on the back two cylinders.

I am seriously hoping this isn’t a bad seal so I figured I would ask you guys if there is any other possibility. No it is not coming from the valve cover.
 
If it's a new build, it's probably assembly oil.
 
valve seals are easy, lets hope its not a bad guide. But from an engine builder is not a good sign. Call him before you dig into it.
 
pishta said:
valve seals are easy, lets hope its not a bad guide. But from an engine builder is not a good sign. Call him before you dig into it.
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I dont plan on digging in any farther than doing a leakdown test. I paid for new seals and guides so if there is an issue this engine is going back to him.
 
Doogievig,

I guess that it did not smoke or otherwise act funny on the stand? Were you there? I can't visualize oil puddle on the valve. It's inverted right? I guess that this was the only time you saw it, did you rotate or crank the engine to create any oil pressure? Is it weeping out? Did you pull a valve cover and take a peek?

Best of Luck!!!

Marion
 
doogievlg said:
The engine was broke in on a dyno and has at least five pulls on it. Also isn’t it a bit strange that it is only those two valves with it?
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Any residual oil in the heads will run to the back when you install it and the engine is slanted back. So that may explain being around the back valves. But the oil drain holes ought to keep it from getting backed up high enough to flow over the exhaust guides and past those 2 exhaust stem seal. Edelbrocks will build up a deeper pool of oil back there. Hopefully, the oil drains back there are not blocked up for some dumb reason.

More than 2 exhaust valves ought to be closed at a given time so you would indeed expect oil elsewhere if it a general valve seal problem.

I'd start by:
  • pulling a valve cover and see how much oil runs out the back corner
  • make sure those 2 valves HAVE seals
  • use a mirror and look into all the ports and look if there is signs of oiling down the valve stems
  • check the plugs as suggested
 
Now it hasn’t run in the car yet? but Because of the angle of the motor I get deeper pools of oil at the rear ends of the heads. What style of valve seals? If they are the o rings it may have just been engine angle and o rings allow some oil through. Did you prime it?
 
furrystump said:
Now it hasn’t run in the car yet? but Because of the angle of the motor I get deeper pools of oil at the rear ends of the heads. What style of valve seals? If they are the o rings it may have just been engine angle and o rings allow some oil through. Did you prime it?
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Only ran on the stand. It was 11 PM when I discovered the oil last night so I didn't take the time to pull the valve cover on that side and get a good look at the seal.
 
I just got off the phone with the engine builder and he said that it shouldn’t be an issue. It did run good during the dyno pulls and there was no smoke with good oil pressure. It still seems very odd to me. I’m still going to do a leak down test on it and check the seals before installing it.
 
If they are J heads, the "valve seal" really is just a short umbrella that keeps most of, but not all, of the splashed oil from the springs off of the valve stem. There's always going to be some oil in the guides, if there weren't, the valves would seize up in the guides. I would ask the builder how much clearance they machined into the guides. More clearance, more oil.
 
Take a picture of the seal. It could be an umbrella, or a positive seal, or just the square o ring.
 
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