Need an exploded view of .............................

[UD LOSE]

a 340cc Yamaha engine. Somewhere in the early 80's. Can anyone help? I don't have comp. in the left cyl.. Oil doesn't give it compression either, so it must be in the reed valve??(if it has one)? Thanks, Mike

[reelrazor]

http://www.yamaha-motor.com/products/categories.asp?lid=6&lc=sno

Pull down the menu from 'parts and service' and go to parts catalogs.That will open a new window, at the top left of that, under 'catalogs' select 'snowmobiles' and it will give you a tree on the left with years. You will have to start at 1980 and open all the 340 sleds. The first page on each will have the engine i.d. #. You will have to find the one that matches yours.


" Oil doesn't give it compression either, so it must be in the reed valve??(if it has one)? "

I don't believe Yamaha made a 340 in the 80's that HAD reed valves, but oiling a two stroke cylinder to see if it is rings or valves doesn't work on two strokes. You might have a broken ring, bad head gasket or a holed piston, hell, look in the hole...is the piston moving?

[UD LOSE]

That's what I was looking for! Thanks! Now that I think about it, you are right about the "oil" trick. Hell, I should have known that! I am helping a friend out & he caught me after work. I told him to check some things out & he found no comp. on 1 cyl.. I will see if he tore it down tomorrow. Mike