Pressure/vac testing question

[wseibert]

In videos I've seen metal plates fabricated to block off the intake and exhaust sides of the cylinder with the pressure vac hose going into the spark plug hole via an adapter.

My question is whether I can use red rubber sheet packing from a plumbing supply or hardware store to make the blanking 'plates'? I don't have access to the tools I need to make the metal plates.

I'm testing the clutch side crank seal I've replaced on my recently purchased MS440, and I just got a Mityvac. Thanks.

Will

 

[Breckinridge Elkins]

My question is whether I can use red rubber sheet packing from a plumbing supply or hardware store to make the blanking 'plates'? I don't have access to the tools I need to make the metal plates....

That's exactly what I did.
I bought the sheets of rubber gasket material and a sheet of plexiglass. I cut the plexi with a jigsaw blade specifically made for that material and drilled holes with a brad point drill bit. Once you roughly cut the plexi you can lay it over the ports and mark the bolt holes with a sharpie. If you want, you can add a hose barb or schrader valve over the port.

 

[pioneerguy600]

An occluder between the muffler and one between the carb is all I use these days, I have an assortment of metal plates I made that fit almost all saws I encounter but don`t use them. I made my rubber occluders from 1/4" thick black rubber. Google occluders and you will find them,just a tapered cut slice of rubber sandwitched between the carb and muffler.

 

[J D]

Yup, doesn't need to be anything flash, a piece of inner tube wedged between the cylinder & exhaust/carb works just fine. Most tyre shops will happily give you an old tube

 

[pioneerguy600]

Most any hardware store or plumbing supply shop sells an assortment pack of gasket materials very reasonable priced. In those packs there is handy sheets of black rubber, a bit harder or dense red rubber, and cork sheet material I have used to make sealing gaskets for vintage saws, think oil and fuel sealing rings for the caps. Just an alternative supply rather than chasing down innertubes .

 

[muddy42]

Yes, even wood will work with rubber inner tube. Then the best way to locate leaks is to put the whole disassembled saw under water and look for air bubbles.