Vintage Mcculloch Power-Mac 310

[monster318]

Hello All,
I have an old Mcculloch power mac 310 chainsaw that I picked up at a flea market this past fall. The reason for picking it up was both my father and grandfather had this exact same saw and used theirs for years on end. Also this one was in awesome condition at a good price so I got it. When I got it home...i got it running...but it had some issues...so I figured for the price I got it at wouldnt hurt to get some maint. done on it. So I got a carb kit, air filter, fuel filter, new throttle cable, Spark plug. I soaked the carb for 2 days in thinner and ran it once through my ultra-sonic cleaner. Put everything back together and she fired right up!

But what i cannot seem to fix on it is if i am running it, it will run great, but if it idles for about 15-20 seconds right after cutting with it, it will shut off...not even sputter or anything..just as if you shut the ignition off, and if you pull the rope..its starts right back up and keeps on cutting.

So I took it apart again and replaced the fuel line and the vacuum line going from the engine to the fuel pump on the carb, and rewired the whole chain saw, thinking it might have been shorting and killing the ignition somehow..but it still did not fix it

any other ideas?

ALSO: When my father became aware of this problem, he said his old Mcculloch did the same exact thing, so I guess its a Mcculloch problem, I am just trying to find a solution to it!

 

[DT86]

Of all the saws my father and grandfather had not one of them would idle for long. I think it may just be the nature of those older 2 strokes.

 

[Fixemall]

Most of those old saws need crank seals, I would not keep running it until I did a quick pressure test.

 

[monster318]

Well I believe I have finally found the problem, These saws have a plastic intake manifold between the block and the carb, on this manifold there is rubber grommet that is the actual mating surface between the carb and the manifold. That grommet was dry rotted very bad and basically falling apart. I replaced that with one from a parts saw I have and it started right up and runs strong!

I guess a weekend out at our cabin cutting wood will determine if that was the cure or not :thumbsup: