BigRed96
ArboristSite Operative
Good Day All, I am currently fighting a fuel issue on a 290 that we rebuilt using a 390 piston and cylinder. This is the second one I have rebuilt and the other runs great. My question is how easy is it to accidently get sealant into the impulse hole on the cylinder while putting the bottom end together. I have put two different rebuilt carbs on the saw and it does the same thing. I have faith in my carb cleaning and rebuilding abilities as I have done dozens so I don't think that's the issue. I disassemble, ultrasonic clean, blow out with compressed air, and reassemble using a kit. Right now in order to get the saw to fire up I put it on choke and pull it till it pops, then flip it to the high idle and pull till it fires, it will run for a few seconds and if I try to give throttle in just peters out. The saw won't idle either and just dies when it goes from high idle to normal idle. After stalling I have to full choke to get it to fire again, that tells me the saw has a fuel problem I let my brother seal the bottom end as the saw and parts where a Christmas present and he wanted to try doing the rebuilding, I forgot to warn him to be care not to seal up the impulse line plug. I didn't think he used a large amount of sealant but I may be wrong. I have flywheel/coil gap with a business card as I have done al my saws I have rebuilt. The impulse is the only thing I think could be the problem as I checked tank vent by removing it and blowing/sucking (not funny comments) and it seems to function fine, it has a brand new fuel filter and fuel line. What do you all think? Should I just bite the bullet and tear the saw back down?