Chainsaw Repair

Saw now runs turned on l/r sides.  Problem now is surging when in bucking position.

Sorry, I came in a bit late on this. What you mentioned seems typical of a bad jet valve (check valve) in the carb. Air blowing into the metering chamber through a badly holding jet valve will lower the fuel level in the metering chamber.
You hold the saw sideways, it runs lean and rpm goes up. You hold the saw the some other way, the saw runs rich and dies.
You try to rev and the engine sounds like it is running out of fuel.
If you had not mentioned the above symptom, I would have told you to check the ignition system, viz. the ignition module and the short circuit wire.
An ignition module that is on its deathbed will show all signs of being healthy, except when the saw starts up, it will just supply current for a few sparks then go on the blink. Till to try to start up again.
The short circuit wire (the black one ) could have lost a bit of insulation and could earth out the current when the bare wire comes into contact with the body.

Joe

I'm not sure exactly which style ignition coil is used on that model .However on an 042 which uses a self advancing coil I once had a similar problem .

The way that thing works is through the electronics within the circuitry as the engine reached a certain RPM it would self advance .In that case the modual would cycle on advance ,then to retard .About drove me nuts until I changed the coil with a known good one .

I had the same or almost same thing happen on a Briggs and Stratton 18HP engine .Except the modual would stay on advance thus firing early and when warm it was impossible to start  .It nearly let all the magic smoke out of the starter .Not good .