McCulloch Chain Saws

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I have a PM55 with carb issues. When I first took the carb apart the lever was well below the normal set height and it did hold pressure. I rebuilt the carb and can't get it to hold pressure. This is a Walbro SDC with the single adjustable jet. I have the Walbro tool for setting the level on order. Anyone have thoughts on this?
Did you inspect or replace the inlet needle?
 
And I sprayed the gaskets with soapy water. No leaks there.
Take some tubing and push your needle into it (not the pointy end lol) and ten apply a small amount of lapping compound or toothpaste onto the end of it and gently spin it against the seat. It doesn't take much but that should fix a damaged seat if its slightly pitted or banged up.
 
Not sure if this would be relevant, but I have seen kits for the SDC carbs of far east origin that had a shorter fuel needle. That would explain the over bending. I’m on the road this week, otherwise I would measure a good one for you.
 
Did you replace the metering needle? Even so, sometime the needle seat will be dirty of have a spot of corrosion. I use a bit of toothpaste as polishing compound and really lap the needle to the seat.

The SDC carburetors utilize a forked metering lever that must be connected to pip on the metering diaphragm. You wouldn't be the first one to miss that little detail with reassembling a carburetor.

Mark
 
Just when you thought you'd seen everything...

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I will do some digging to see if I can find the Popular Science magazine article that discussed the virtues of McCulloch's new high speed plywood saw.

Mark
I have so many questions..........
What's the button for?
The recoil?
The colors look to match factory paint, so came from Mac that way?
Is it meant to be operated from the muffler side, with the deflector blowing up to your left?
What kind of chain is that? It looks like old two man chain with no rakers.
 

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