Case Reassembly - Yamabond

[stanG]

I'm getting ready to reassemble the cases on my 1st gen and have a question about using the Yamabond #4, Would I spread a thin layer of the sealant on just one of the case halves? I can see about 95% of this stuff squeezing out on the machined surfaces when the bolts are torqued. I noted that the service manual states to keep sealant at least 2mm away from bearings. Any suggestions here?

[Venturous Randy]

I'm getting ready to reassemble the cases on my 1st gen and have a question about using the Yamabond #4, Would I spread a thin layer of the sealant on just one of the case halves? I can see about 95% of this stuff squeezing out on the machined surfaces when the bolts are torqued. I noted that the service manual states to keep sealant at least 2mm away from bearings. Any suggestions here?

 

I just put it on one side. Make sure the surface is real clean like you wiped it with an alcohol pad. It may help to do a test fit a couple of times as it can be a little tricky getting the forks to line up. Also, I just put it on the surfaces that are exposed to the outside.

RandyA

[jeffg]

I've probably rebuilt 20 bike engines and 3 or 4 VW aircooled engines using Yamabond or the Threebond equivalent. I just put it on one side. A lot squeezes out which is why they say keep it a little bit away from the bearings.

 

Make sure that the mating surfaces are smooth, clean and dry. Once I get the old sealant scraped off as best I can with the gasket scraper, I use a Scotchbrite pad to clean up the surface and then brake cleaner to degrease.

 

If you get it clean, you won't have a leak.

[icebrrg3rd]

What is the Threebond equivalent for Yamabond 4? And where do you get them for a good price? Inquiring minds want to know...

 

I did find the Yamabond for about $10 plus shipping, just seeing if there was better price. Couldn't check ebay at work.

 

-Andrew