82' 750 Maxim Oil Leak out of Head Bolt base???

I spent about 30 minutes in the search trying to find a similar instance and I could not, so here we go. Bike has had a small oil leak since I bought it, when parked,maybe 3 drops at most a day, when running it leaks much faster. It looked like it was head gasket but after a closer look it is originating from the base of the outside And 2nd inward head stud. After the ride I looked close and could see it bubbling up from the base of the stud.

What are my repair options?

Is there an o-ring on the base, or is it a silicone seal or interference fit?

All the other studs look fine and have no sign of leaks.

Thanks a ton!!

 

Check around the cam chain tensioner and oil delivery pipe to the head. They are the most likley places for oil to leak. They can leak oil and it will run down the cylinder fins and collect around the studs. How about the valve cover gasket. There is no pressurized oil around the studs , its probably coming from somewhere else.
You don't really want to remove the cylinders, its a PITA.

 

I also have a leak in an odd place but it is from the right side between the cylinder and the head. I think it is the oil feed line for the head. And what is a PITA?

 

PITA= pain in the ass

 

Not so on the 650/750s, witness the two copper washers that seal the two left cylinder head studs. They keep the oil from the top end oil gallery feed from spewing out all over the head.

That we can argue but in general I'd agree. The base of the cylinders are sealed with very thin o-rings and a gasket (yes, both) that do go bad once in a while.

 

Thanks for clairfying Robert, I thought my 750 had that oil pipe. Though its been 20 years since I worked on it, Sorry guys for the wrong info.

 

No worries, I've seen oil feed pipes on a few Yamaha models. Helps me appreciate the awsome design of the XJ power plants! Glad I don't have to futz with that.

 

If you saw it bubbling out at that point then it's probably a pretty good bet that's where it's coming from.

You can try retorquing the head; otherwise it might be base gasket time and yes it's a PITA.

 

I'm confused by the photo.
That spot on my Bike is Cast. Not a Mating Surface.

What's leaking?
A Crack or a Mating Surface?

 

After a closer look, it seems there are plastic "sleeves" on the head bolts that are 50% there, the rest of the sleeve is breaking off or broken. At the base of the head stud it was bubbling up. I untorqued the head and re-slammed them in and no leak it seems. I will know in the morning for sure.

RiCo, yeah pic wasnt the best angle, but I was trying to point at the head stud base.

 

I'll bet it's upstairs in the vicinity of the cover gasket. Capillary effect oftentimes leads the owner to believe the leak is elsewhere.

 

Is your engine vent plugged off? Seems strange to get oil pumped out at that location.

 

You might as well Re-torque the Head Bolts.

Takes about an Hour.
Lube the Washers and Fastener Threads.
Get an accurate force on all the Studs.
It's a low-cost maneuver.