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Some run issues with carbs and what the fixes were.
Problem, saw runs eradic and eventually dies. Also passes a crankcase pressure/vacuum test and is fine mechanically and has good spark.
Leaving the fuel system suspect.
Carburetor passes a standard fuel inlet pressure check.
However, it fails when a light vacuum is applied to the primer outlet, with the inlet blocked off.
Upon disassembly it was found that one of the little flaps on the fuel pump side was lifted up with some crud growing under it on the carburetor body due to the use of ethanol fuel. This allowed a short circuit to the main nozzle, which makes it uncontrollable.
Carburetor was cleaned along with a new gasket and diaphragm kit and reinstalled. Tests were now passed as well as running confirmed saw was back in proper condition.
Problem, saw runs eradic and eventually dies. Also passes a crankcase pressure/vacuum test and is fine mechanically and has good spark.
Leaving the fuel system suspect.
Carburetor passes a standard fuel inlet pressure check.
However, it fails when a light vacuum is applied to the primer outlet, with the inlet blocked off.
Upon disassembly it was found that one of the little flaps on the fuel pump side was lifted up with some crud growing under it on the carburetor body due to the use of ethanol fuel. This allowed a short circuit to the main nozzle, which makes it uncontrollable.
Carburetor was cleaned along with a new gasket and diaphragm kit and reinstalled. Tests were now passed as well as running confirmed saw was back in proper condition.