I have been trying to fault a problem with a mcculloch mac cat chainsaw. The saw starts up and runs fine, but after about 5-10 mins work it stops. After a few mins it will start and run fine again. I have checked all the fuel lines and primer bulb for leaks/blockages, stripped down and cleaned the carby, the diaphram and gaskets still seems in good nick. Any ideas on what may be causing the problem? the carby is a Zama.

Cheers
Paul