VintageVmax.com

Hi All,

I picked up an 87 Vmax last year as most of you know if you have been members for a while. I also restored an 86 as you can see on the picture page under "George". I got the 87 running and after a little while it started to leak antifreeze at the thermostat housing, it was also blowing whitish smoke out of the pipes so I bet the antifreeze was getting by the O-Ring gaskets. More than likely the thermostat was frozen so pressure built. I have a new OEM thermostat housing, thermostat, and a set of O-Ring Head gaskets. Any tricks or advice? I imagine that I would want to coat the O-Rings in grease to keep them in place while setting the head. I have all of the sequencial torqu specs as well. Would white grease be o.k.? Also, any tricks for keeping them in place while setting the head??? I didn't need to do this on my 86 during resto, I only needed to pull the motor so I have not wrenched on a 540 as of yet with the exception of carb cleaning....

Any advice would be greatly appreciated.

George

dont greese them, it will rot the rubber, just use a few drops of super glue to hold them in place.

A little grease would be fine to help keep the O-rings in place. Won't hurt a thing. I would not use any kind of quick setting glue as the O-rings need to move while the head is being torqued to seat in the groove. Glue could cause problems here. Do NOT!!! use any type of silicone based sealants for heads, cylinder bases, crankcase halfs or any other areas that come into contact with fuel. Use a proper type of flange sealant that is compatable with fuel.

One other thing I have seen with cylinder O-ring sealing issues on these engines is that some cylinders that have been sleeved will have a deeper groove cut in them for the cylinder O-ring than the OEM chrome bore cylinders have. If that's the case new O-rings may not be thick enough to seal.

Good Luck, Phil (opsled)

Last time I had after market gaskets, to me the fit was horrible they were to large and didn't want to lay down in the groove. In karting we use the same style o rings for a carb bowl gasket. We use methanol ae a fuel. Soaking the o ring in a little alky causes it to shrink up some. Soaked my VM rings and they fit nice and tight in the groove, and stayed there

Thanks for the replies!!!
Bob, when you say Alky... is that alcohol???? I haven't tried the fit as of yet, but of they are big I might need to do that.

Thanks again for all of the responses. The manual calls for Yamaha Grease.... is that like simple white grease????

Again many thanks!!!

I used Methanol which is what we use for fuel in karts. I had after market gaskets Would assume it depends on the rubber the gasket is made from