Dolmar PS 3410 Ignition trouble?

[pycoed]

I have a little PS3410 which I use for hedgelaying/coppicing etc. I got it from Andrew on here a good few years back. It's perfect for the job but the other day I was cutting some hazel rods from a stump & I heard it missing at high revs. I thought I'd clean up the stump (about 12" - bar is 12" too) & it was missing badly right throughout the cut. Hazel is quite hard & the little saw was at full capacity, but finished the cut. On revving it was popping & backfiring badly at revs. Switched it off, gave it 15 mins rest & it wouldn't start at all. Following morning  it started fine but was still missing at revs. Put in a new plug - just the same. Checked air filter (desperation!) - was fine & now saw won't start at all. No spark at plug, but if I use a spark tester there is a weak spark at the lamp, but not enough to jump a plug gap.

Coil is a silly two piece affair with a separate trigger module (why why why? its a CHAINSAW for Gawd's sake not a racing car) any hopes of sourcing one sensibly priced in UK - they seem to be $130 in US !!!

[billpierce]

Have you tried andrew?

 

Or miles machinery or l and s have makita parts I think

[pycoed]

I was hoping Andrew might see this, since I seem to have lost his contact details! Cheers.

[openspaceman]

@shavey??

[Fatboy2017]

I heard of someone used one of these in conjunction with his coil

 

Ignition Coil – Red – 2 Pin | DBRacing

DBRACING.CO.UK

 

[pycoed]

Thanks - that's interesting - I have used the Atom ignition on a couple of old magneto engines, perhaps something similar could be cooked up using this - looks like some experimentation is called for. For now I'll carry on with my old Husky.

[pycoed]

Success! My problems were simply a fracured earth strap from the coil frame to the saw body. The first coil next to the flywheel, where you would expect, has an earth strap to the saw body, since it is mounted in the plastic housing (though with nice brass inserts). This strap (no.125 in attached)  had fractured just where the screw connects it to the coil. I had thought this was just a washer, but once fully clean I could see it had a little tab with a broken face. 

Fiddly job to clean, drill & solder a wire to the existing strap (I didn't really want to pull the flywheel to get at it) but 20 mins later & saw is back to normal👍