OIL LEAK VALVE COVER OR CYLINDER GASKET

I have had my Maxim about 3 years. This year, the oil leak has gotten to be a regular oil shower, But only on my left pant leg. I was looking through the Yamaha Service Manual and see that there is a gasket on top of the cylinder (which I would think is the valve cover gasket.) and one on the bottom of the cylinder. Is the bottom one the Head Gasket? The whold front of my Maxim is now oily.

HELP!

 

The top one is the valve cover and is most likely your problem. A new gasket is a good idea but not always necessary. The old one may just need a bead of high temp RTV many of which are available from Permatex. So pull the cover, clean the gasket and mating surfaces and replace. Remember to let the RTV sit overnight. Trust me, I works better that way.
IF the headgasket is leaking you may not know for sure until you get the valve cover to stop leaking. Replacing the headgasket is not a job fo rthe faint of heart or anyone in a hurry. I requires removing the camshafts and a close check of the cylinderhead for warpage. The most likely reason for a headgasket to leak other than age.

 

Please allow me to offer my opinion concerning Cam Cover Leaks.

When the Cam Cover Begins to Leak it is because the Cam Cover Gasket is failing and a NEW Gasket is DUE.

The use of Sealants to Cam Cover Gasket related installations is LIMITED to those Models which employ separate "Half-Moon's" on the Cylinder Head.

Otherwise, the Cam Cover Gasket is designed to COMPRESS between two absolutely clean mating surfaces.

Any foreign matter and any sealant used between the two surfaces only serves to obstruct the oil tight seal maintained by squeezing the gasket between those two extremely close tolerances of the design.

The best treatment, to insure a no-leak Cam Cover is to thoroughly CLEAN the Cylinder Head Mating Surface. Spotlessly Clean.

Using an Artist Style Paint Brush ...
Paint-on a very thin coat of Light Machine Oil (3 -'n- 1)
Do the same on the Surface of the Gasket.

When the Cover is tightened-down in the "Small incremental tightening fashion" as the Manufacturer suggests ... the sheen of oil will allow the surface of the Gasket to SPREAD as it Compresses.

The seal is Oil Tight

 

The reason I suggest a gasket sealant is due to the bolts that hold the cover on. The thicker part of the bolt shank will sometimes contact the cylinder head. This will not allow the gasket to compress and form a proper seal. rather than remilling the bolts we have found that sealant fills the gap and stops the leak. I use this on my cover which doesn't have the seperate half moons. A close inspection of the mating surface will show indentations where the bolt bottoms out on the cylinder head. For more clarification on this matter you can contact Dwayne Verhey.

 

Most likely the valve cover gasket is what's stressed & need's some service or replacement, Go along with any of the tip's mentioned above & im sure it'll be a safe ride to fix the oil leak once & forever.

Might as well check the valve cover bolts prior removing to make sure none of them are loose. these do tend to break loose since the vibrations are pretty strong if traveling at mid/high rpms or on long trips or bumpy ones. not very likely but definitely worth a try

 

My valve cover gasket is also leaking and I was thinking of replacing it until I started calling around for the part. I called two Yamaha dealers in the Minneapolis area and they wanted $65-85 for the gasket!

That's a lot of money for a gasket.

Does anyone know where to get the gasket much cheaper? If not, I may have to try the RTV solution.

 

partsnmore.com has them for $19. But they also have a $35 minimum order. So look around for some other neat stuff like the rubber washers on the valve cover bolts. $2 a piece.

 

$70.00 for a Gasket that lasted 25-years.

That's about ... what??? $2.80 per year?

That ain't bad for stopping an ugly leak!

 

Are the rubber seals for the bolts the things that are listed as the valve stem seals or the cam cover seals. I would think that valve stems seals are for the valves themselves. I'm guessing when they say cam cover they mean the same thing as valve cover. How many of those cam cover seals should I get? Do all 12 bolts have a separate seal?

This place is a great deal over buying from a dealer. With the $35 minimum order and $3 flat rate shipping I get many more parts for $38 than the dealer wants for just the valve cover gasket.

Too bad they don't list brake shoes and pads. Mine are starting to get worn and I'll probably replace them over the winter.

Here is my shopping list:

Valve cover gasket $19
Alternator brushes 2 @ $5 each
Cam cover seals 3 @ $2 each

Edit: They do have brake pads and shoes! I'll be well over the minimum now! They don't list the brake parts in the XJ650 Maxim section, but when I look under the brake parts section they have the maxim parts listed.

 

I believe you are referring to the seals that go on the camshaft cover (valve cover). You need 8 (I believe their listing indicates this).

These seals are for the 8 outboard bolts. The four inboard use a different seal and Partsnmore doesn't list them.

The outer 8 bolts have a shoulder in them that bottoms out on the head. The seals compress to apply the tightening pressure to the camshaft cover. When these seals get old they become stiff and may not hold the cover down tight enough.

The inner four actually tighten against the camshaft cover, so it is less critical that they be flexible.