Partnet K650 Active 111

[howburn]

To follow-up on all the advice and help I have received.

The owner brought back to me the barrel and piston, piston picking up on the exhaust side, some witness marks on the bore. Top of piston normal black colour. Both piston rings complete, but bottom ring stuck in where dealer mechanic missed the gudgon pin with the hammer, and consequently the piston is quite bashed up (think he missed lots of times)!

After reading your comments, replies and the workshop manual, I think it was down to air leaks the damage doesn’t fit with the description on the workshop manual for over revving ether.

Going by the witness marks for the gasket faces for the barrel to crank case and carb they don’t look perfectly even, air could have leaked through. Explained to customer that crank seals could be leaking or the crank case could even be cracked and to the best of my knowledge this has not been checked.

Spoke to the supplier of the coil and he strongly doubted that the coil was the cause, has supplied loads been in business 40 years. As goodwill and without asking he supplied a new barrel and piston.

I have had somebody else look at the damage and their thoughts fit with what I have described above, as does the coil supplier.

 

So to summarise the original damage, the general thoughts are ether poor workmanship when fitting barrel and piston or other air leaks. The owner did say the first he was aware that the saw was not right after they had repaired it was when it constantly ticked over very fast (air leak?).

Suggested he went back to the dealer and asked a few questions, did it run OK when they put it back together? Did they check the engine revs? If the coil that was fitted was so detrimental why did they re-fit it or advise him?

And also say that he had had advice that the damage may be down to what I have said above. The head mechanic/Forman replied "spoken to Husqvarna and they say it’s the coil". The dealer would take no liability what so ever.

I spoke to Husqvarna about the coil yes it could cause the damage the dealer claims.

I however in this case disagree.

Cheers