Valve cover gasket leak

[DMW]

Removed valve cover cyl 2&4, leaking. Had replaced once before around 50,000 miles, now have 98,000. Was leaking into spark plug area. The gasket had splits in it. Almost looks like it melted.

Has anyone seen this before? Pixs attached.

Is their something I need to check before replacing?

 

 

[slowrollwv]

Looks like they may have been drawn down too tight or a bad set of gaskets. I do not think they would deuterate from heat.

[MiCarl]

You shouldn't be able to draw it too tight. The proper bolts have a shoulder and the rubber donuts apply the correct tension to the gasket. Make sure you have the correct bolts. Put in new donuts with your new gasket.

 

When the donuts don't get old the rubber looses its elasticity. Normally this keeps them from applying enough pressure on the gasket but in your case maybe they got hard and applied too much pressure.

[Marcarl]

You may have used the wrong kind of sticky material to hold them in place when you installed them. You don't want to use something that gets hard.

[Flyinfool]

Or either the head or the cover were not clean leaving some of the old gasket in there.

Or whatever you used to hold the gasket in place was not compatible with the rubber of the gasket.

Or at some point you added something to the oil that was not compatible with the gasket.

Or while you were installing the gasket it was trying to slip out and got pinched and cut before it finally slipped into place.

 

Any normal amount of heat should not hurt the gasket. If at some point you over heated the engine it might have damaged the gasket.

[luvmy40]

If the XVZ engine got hot enough to do that kind of damage, I'd bet it would not be in running condition any longer.

 

I have an '81 Yamaha Seca 750(air cooled inline 4 that runs lean) that was tortured with a 160mi. daily commute in the Phoenix heat for two seasons and the rocker box gasket(same setup for the most part) did not look damaged at all.

[Karaboo]

Just curious, what brand gaskets were used at the 50,000 mile service? That could make a difference. Those look scary.

[DMW]

Update,

 

I think I found the problem with my gasket. I used orginal yamaha part. I did not want to buy the bolt grommets, just to pricey,$9 ea.( I can't under stand why they are so high, the ones for my previous GoldWing were only about $3 ea. and still are.

Used a suggestion from Tech section about using washer. Just checked I have a thinner washer on the 1-3 covers, the ones on the 2-4 are twice as thick!

Therefore, I created the problem!!

Going to do some research to seeing if I can find a better price on the grommets.

 

Thinks for all the input,