Engine cutting out on undercut

[smallengineguy]

Hello.

I'm stumped.  I finished rebuilding my 330 with new boot/fuel line etc. 

The chainsaw runs great when I'm doing normal bucking, but when I attempt an undercut, the engine starts to cut out immediately (almost as if it is losing spark).  And then if I decide to go back to normal bucking, it runs fine again.

Any ideas on what the problem is? 

Thanks.

[undee70ss]

Does it do it will a full tank of gas? Gas line in tank may be to short or stiff uncovering fuel filter.

[smallengineguy]

Position of saw and amount of fuel in tank make no difference. The engine starts to cut out as soon as the top of the bar hits the wood. It seems like ignition.

[undee70ss]

How are the AV mounts? Inspect wiring and look for frayed wires.

[smallengineguy]

Av mounts are good. I have not checked the wiring. I'll do that.
Thanks.

[blythkd]

I agree with Undee on the wiring. I believe you can pull the muffler to take a look at the switch wires. I've seen them bare in the past. Undercutting could be shoving the muffler back against the switch wires.

[smallengineguy]

You guys are absolutely correct. Thanks. I took the muffler off and the muffler shield was rubbing on the switch wire when the bar gets pushed down. I've never had that happen before. I learn something new every day.

[onlyhomelites]

Ditto on the wires. I just finished up a 330 with the opposite problem; the ground wire was broken internally, so the switch wouldn't work. I like to zip-tie the leads over a bit closer to the spark plug wire on reassembly.

[farmer1]

I have had both of the above described problems befor with the 330s. Once I bought a used coil just to get a good kill wire.