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
 

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