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3000 oil leak from side of engine

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GregW

GregW

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So I tracked down an elusive oil leak on my engine. There were small puddles on the flat recessed areas just underneath the sparkplugs. At first, I thought the usual which would be the valve cover gasket, but there was no oil on the upper part of the head. Pulled a plug wire and using a mirror, I found a threaded hole. Turns out, the six studs for the rocker assembly are leaking. What might be good for sealing those up? Hylomar, Locktite, anti-seize, or the old favorite, Teflon tape.

Thanks,
Greg
 
Hi Greg,never heard of that one.However, I think I would go with the Teflon tape.A similar problem in the Daimler Engine allows oil into the spark plug tubes the tape stopped it cold.---Keoke
 
I'm glad to hear that someone has a similar problem. I've had my 100/6 engine overhauled a bit more than a year now and although it's running fine, I also have the above mentioned puddles on the flat recessed areas.

The difference to GregW is that these puddles are only on cylinder 2 , 4 , and 6.

Is this the same problem? I guess this means that the engine would be burning oil?

Like always, in awaiting your responses I'll have a /ubbthreads/images/graemlins/thirsty.gif or two.

OOps forgot that I'm on a water diet this month. /ubbthreads/images/graemlins/cryin.gif
 
Hi Keoke,
Thanks, I think I’ll live with the leak for a while. I’ll do the Teflon tape chore when I re-torque the head.
 
Hi Higgins,
If your leak is the same, it won’t be burning oil. Which is not to say there isn’t a leak somewhere else. /ubbthreads/images/graemlins/rolleyes.gif
 
Please excuse my being dense but I didn't follow the mirror, threaded hole and six rocker arm studs. I have this leak too and have for years. Are you saying the studs that hold down the rocker assembly are not seated all the way down? I didn't follow where you where looking with the mirror.
 
Hi TH,
Sorry, I should have re-read my first post before sending. The threaded holes for the six rocker pedestal studs on the spark plug side are drilled all the way through the head. I didn’t know this until I pulled a spark plug wire and used a mirror to look up in the recessed area above the plug. Sure enough, I could see the end of the pedestal stud. I thought it was a mistake (on my new aluminum head), but I checked the original head, and it has it too.
 
Ah, thanks. So you think the oil is comming from the valve area? Can you see oil on the bottom of these studs? My leak appears to be between the block and head. Very small and I see them on MANY Healeys. Can you remove the rocker arm and just tourque the studs tighter? (If I followed this correctly)
 
Yeah, I’ll tighten them down. I don’t recall if there was a specific torque setting for these studs. I think I’ll add the Teflon tape anyway, ounce of prevention as it were.
 
I doubt if torquing the studs tighter will help. Studs should never be tightly bottomed out either in a blind hole or an open hole. In this case of an open hole, the leakage is likely along the threads & sealer would be the only way to stop leakage.

Any time a stud is tightly bottomed out there is a possibility of pulling the top hole threads up or distorting the surrounding surface which will prevent the mating parts from fully seating & sealing.

TH, There is a slim possibility that retorquing the studs would stop the head to block leakage but doubtful. Maybe worth a try.
D
 
Hi Dave, on the six clyinder engines a torque of ~ 35 FT/Lbs is required on the cylinder head studs. That is pretty tight if you do not do it there is a chance the head after installation will leak---Keoke
 
As I said, it's worth a try. I don't think that torquing to 35 ft/lbs necessarily means that the stud is bottomed out in the threads with this much force.

Even if the stud was firmly bottomed out on the top thread, there is not likely to be a perfect seal between the stud shank & the head. I would certainly use sealer.

To each his own /ubbthreads/images/graemlins/wink.gif
D
 
Okay, this sounds like a plan for the next time the valve cover is off but if oil is in fact getting into the chambers how does it get out the side of the block and why aren't the plugs black and shinny? If oil can get out then the pressure test would be lower due to poor sealing??? Is the compression blowing the oil out? /ubbthreads/images/graemlins/confused.gif
 
Hi TH,
These six threaded holes aren’t under any kind of real pressure, it is more of a gravity leak. They go from the top of the head straight down to come out above the spark plugs. There is probably two inches of metal between them and the combustion chamber. I’ll take some pictures of my spare head today and show you where I mean.
 
NO NO TH,the oil that collects in the void around the studs creates a head.Consequently, if there is a passage to the outside world containing no head it will simply seep out until the void is depleted of oil.--Fwiw--Keoke
 
In the intrest of sanity and such, how about cleaning the bottoms with a squirt of carb cleaner and useing some sealent untill you get things apart later to put on the teflon tape?? Bad idea huh? Oh well.
 
Thanks, I misunderstude. Greg said he pulled the plug WIRE. I misread the wire. I thought he pulled the plug and was looking into the combustion chamber with a mirror. Like duh! Now I'm on track. SORRY (Hey, I use to be blond)
 
Hi TH,
Well I pulled the heavy head off the shelf, took some photos, struggled to hoist it back on the top shelf, and tidied it up with Photoshop. I would feel soooooo unappreciated if you didn’t look at them. ( end guilt trip) Anyway, the highlighted area on the right is where the stud peeks out and the left side shows the stud from the topside.
/ubbthreads/images/graemlins/grin.gif
224858-headhole.jpg
 
AN where is the picture Greg do they also change sides when posted?????--Keoke-

OK OK it just showed up---Keoke- /ubbthreads/images/graemlins/grin.gif
Very interesting what year is your car and the engine type Greg ?
 
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