Oil leak after valve gasket replacement XJ750

So...the bike leaked oil on the right side primarily on the jugs. I replaced the valve cover gasket, used red gasket sealer on the top side, oiled the bottom side, bolted down w/o over tightning. So I take the bike out for a 25 mile ride, come back, and there is a film of oil all over the #4 carb boot, spark plug wire, and all over the right side jugs/motor case.

Is there any other problem that could be causing this? I'm puzzled because if I botched the gasket wouldn't it be leaking in other places? If it still leaks in the same place is it something other than the gasket?

 

Did you replace the "donuts" on the valve cover hold-down bolts?

If not, that's the problem.

 

No, and they looked to be in fairly good condition, I guess I was kidding myself.

 

The only way to truly tell is to compare them to new ones.

Those donuts are what actually push the cover down against the gasket & head. If you don't replace them, even a new gasket will leak.

 

Ok so the the donuts are replaced, thanks to Chacal.
So I go for a ride tonight, look down, and see oil all over the right engine case.
So I put the bike on the center stand while its funning and stare at the valve cover trying to see if I could see the leak. I did! Its coming from the intake half moon part of the gasket. So, since the bike leaked with an old gasket and old donuts, and still leaks with a new gasket and new donuts, any suggestions? I really don't want to put black gasket maker down in that spot, but I can't think of anything else.

 

I'm curious what the half-moon thing you are talking about it is... is it the part of the gasket on the right-hand side that faces outward?

I noticed my new gasket is 'missing' a part of the cover, near cylinder 4 on both intake and exhaust (inside of cover) not sure if it leaks, I haven't done extensive testing, maybe tomorrow I'll post a picture. Maybe the gasket manufacturer changed and they are missing a portion of the cover?

I'm sure I'm wrong though...

 

Did you replace the cam plugs (half moon part)? They are like $3.00. Seems silly to go through all that work and not replace them while you were in there.

 

RobDrech

What are these cam plugs?

I basically am used to tearing the bike apart multiple times now... practice makes perfect...

 

They look like this but gray... XJ4ever sells them

I found the part number (sorry!!! they're $6 bucks)

HCP1619SET2 Reproduction CAM-END PLUGS

 

Hmm... I did a little research, couldn't find this part for the 750 XJ Maxim...

I searched Chacal's parts list and found this for the 750 Maxim:
HCP2096 OEM rubber VALVE COVER GASKET, for all 1982-3 XJ650 Maxim models, all XJ750 models, and all XJ700 non-X:
$ 60.00

HCP1625 Reproduction rubber VALVE COVER GASKET, for all 1982-3 XJ650 Maxim models, all XJ750 models, and all XJ700 non-X:
$ 34.00

No mention of cam-end plugs, I think it's for the 650, as the cam-end plugs are available for that model... looking at your signature, tells me you needed these parts, but myself and the OP both have a 750 XJ

Anyone else confirm this? On my gasket, I have two "half-moon" sections built-in to the gasket.

 

The 750 uses a one piece valve cover gasket with the molded cam plugs. I think all the smaller models used separate cam plugs.

 

Yes, that is what is leaking, and they are in the one piece gasket.
I guess I'll take the valve cover off and try to reposition the gasket. If it still leaks I think I'll try a very small amount of black rtv around the cam plug, I just did the valves it shouldn't need cracked open again for 5k miles.

 

The only place you'll need sealant will be in the very "corners" where the cam plug portions meet the gasket itself; and very sparingly.

 

this is EXACTLY what i just searched for on here. did you remedy this somehow? does anyone know?

 

Gee, over a year later and same solution still applies...

Yes, use a small dab of RTV in the very corners, be sure it's a SMALL dab we don't want it squeezed out inside (you can wipe off any excess outside.) I've only had to do this when re-using valve cover gaskets, but it's not something to worry too much about.

 

i just replaced the gasket and the donuts, was thinking of maybe just re-seating it with extra special attention to those half moons, because a tiny drop comes from the bottom of both of them. but you think that your solution on the bottom of those would work?

 

I just replaced my valve cover gasket also (XJ750 K). I took a small amount of gasket sealer on my finger and did more than the corners, a thin film on surface of end piece and let setup for 24 hours. No leakage.