Leaking Head Gasket

I just got mike bike back from getting the carbs rebuilt and my valves adjusted on my 1982 XJ750 Maxim. Now when I ride it appears that the head gasket is leaking oil, to the point that it drips. This was not happening before I had the work done. The mechanic said they didn't go that deep into the motor so it couldn't have been caused by them.

Anyone have an idea on why my head gasket would start leaking now after having that work done? Also, the mechanic suggests that I take the bike back in to them and they will re-torque the heads to see if that tightens it up enough to stop the leak. Is that a possibility? I might as well have it torn down again to replace the gasket if I take it back in - took a month last time to get the bike back since they were so busy.

Thanks for any advice folks might have!

 

Are you talking about the head gasket, or the valve cover gasket?

Post a pic or two; don't let the shop do any "re-torquing." If they "re-torque" the valve cover bolts they'll strip the holes in the head or break something.

Exactly where is it leaking?

 

Are you sure its the head gasket? Oil could be running down from the cam cover. Usually a head gasket will cause a misfire as compression leaks from the "blown" area. Oil leaks just starting from the oil passage in the gasket are rare but not unheard of.

 

I'm pretty sure it's the head gasket and not the valve cover gasket. I'll try to post a couple of photos tonight to let you see what I mean. Thanks.

 

Look closely. Often a leak is coming from somewhere other than where you're seeing the oil.

For instance, a valve cover gasket leak toward the inside on the front can run down thru the small cooling passages in the head and end up looking like a head gasket leak.

The reason I bring this up is that adjusting the valves would require removing the valve cover. If they re-used the original 29-year old gasket and 'donuts', there's a good chance it's what has now begun to leak. The work they did wouldn't have caused a head gasket leak.

 

Thanks Fitz. I'll clean it off and see if it is coming from the valve cover gasket somewhere. That would certainly make sense since they had the cover off. They did say that the put a new valve cover gasket on though (it took an additional week to get the gasket). I'm pretty bummed out since I had to wait a whole month for them to get me my bike back and now it comes back with this problem ($900 later). I think I better learn to wrench and save some labor costs, lol!

 

I'll bet any money they DID'T replace the "donuts" on the valve cover bolts, and the new gasket is leaking.

The rubber/metal composite "donuts" on the bolts are what actually push the cover down against the head/gasket, because the bolts themselves have 'stop' collars on them to prevent overtightening. The donuts get compressed and baked hard and quit doing their job; and even a new gasket will leak.

Re: learning to do it yourself. I just did a valve clearance check, it didn't even use up all of my Sunday morning. I'll be going back in tomorrow to replace the one shim I needed and didn't have.

Heck, for $800 I'd have come out there and done the job for you and still made a profit, travel expenses and all. Even if I'd had to stay over for three whole days waiting for parts from XJ4Ever.

You need a service manual.

 

Yeah you're right Fitz - and I would have even provided the beer/adult beverages of your choice! Gotta get me a service manual and some decent tools if I'm gonna continue on with riding this ol' bike. I grew up owning Yamaha's of this vintage but they were all bought brand new and I didn't have to worry about these kind of maintenance issues back in the 80's.

One other question - I've read some posts referring to a spray-on leak stopper. Is that something I should try to get me by for a while (until I have the head gasket replaced - if needed)? If so, what would you suggest?

 

I had all my head studs walk right out and had to replace my head gasket... my lower gasket leaks now ... +1 on bigfitz, when mine went, it stopped running.

 

Hey Fitz! You're the man! I cleaned off the head and valve covers and started it up to let if run for a couple of minutes and noticed that the oil is leaking from the valve cover gasket near one of the inner spark plugs and is running through the hole to the front of the head. Whew! Now I can take it back to the shop and have them fix it under their 30-day warranty. Many thanks for the great suggestions!

 

MAKE them replace the "donuts" on the bolts. (See pic.)

DO NOT let them try to simply tighten the bolts up; they'll strip them. The bolts have stop collars; the donuts are what push the cover against the gasket. They should have been replaced along with the gasket.

 

Hello , I'm planning on attempting to do the top end in my bike and am ordering all parts off the web , is there any brands I should steer clear from or any I should look for ?

 

I assume you are aware of XJ4EVER? Well regarded around here.

http://www.xjbikes.com/Forums/viewtopic/t=14561.html

 

No I wasn't . Thanks