stephenlamb wrote:
Ok so its not the thru frame bellow. So if the carb is attached and tight where should I b looming for the air leak. And do I half to remove the engine to really check the engine side of the manifold. Thanx
To check the engine side of the manifold properly you will need to lower the engine a bit by disconnecting the rear shock (you won't need to remove the carburetor unless you plan on lowering it more or removing the intake manifold).However... You can check the security of the manifold without doing this. You'll need two 10mm box wrenches, ideally, of different manufacture. The reason I say this is because different brands will have different off-sets; you'll be able to tighten the nut on the top of the manifold possibly 1 to 2 mm at a time, and using the same wrench won't allow you to get the wrench back onto the nut with enough room to turn it, so you'll have to alternate between wrenches as you run out of room (the wrench will hit the cylinder/case). Sorry for making this seem so esoteric.
Getting to the nut holding the bottom of the manifold is simple enough because there is plenty of room. Don't get any ideas about removing the tire to get more access, because you won't find it to be true, unless you lower the engine enough to also remove the cylinder shroud. Of course, remember that if the intake manifold base at the case has a failed gasket simply tightening the nuts won't improve the air leak much.
The second place you'll need to check for a leak is where the carburetor slides onto the manifold. There is a felt gasket that should be greased and stuffed onto the manifold before installing the carburetor. I have been using 2 instead of the usual 1. Grease both of them up and slide them on. The carburetor will then stuff them back up the manifold to close off any spaces that could let air in.
