Craftsman 2.3/16. I am muffed about the impulse

[skippymud]

Hello All

Looking for help. I have a really nice late production red Craftsman 2.3/16 with electronic ignition in hand that does not want to suck fuel

Carb is rebuilt properly and compression is excellent. Fuel line pressure and vacuum tested good at 15psi. Impulse line is clear

What else should I be looking for?

Ken

 

[heimannm]

That is a long fuel line, it can take quite a few pulls to get it going initially, I usually give them a little prime down the carburetor to get things pumping first time around. The impulse signal comes through the carburetor mounting flange, there is no separate impulse line. Do you have the carburetor gasket properly positioned with the impulse passage open?

Beyond that, if the reed is not sealing or the crankshaft seals are leaking you won't build enough pressure differential in the crankcase to drive the fuel pump. I think that model has a detachable cylinder, same story there; if the cylinder is loose the crankcase won't create the pressure differential needed to drive the fuel pump.

Are you sure the fuel pump diaphragm is against the carburetor body and properly oriented?

Mark

 

[skippymud]

Hi Mark

Thanks for your quick response and the info. The mounting flange is positioned properly (impulse hole aligned), reed valve seats nicely, and the diaphragm inside the Carb is mounted properly. So, the saw does run very well if I prime with a 40:1 mix from squirt bottle. With all this, I am thinking the crank seals are weak because once it does run, it runs very well

Ken