Stretchsaws

Agree with above. First and easiest job is to pop off the muffler and have a gander. Work the piston up and down and give the ring a gentle prod with a small screwdriver to check that it does flex. Unfortunately some workshops don't have a clue or aren't interested enough to work on small 2 stroke equipment, so they fudge it off by saying 'not economical to repair.' I know because I've had to do it, it's down to my service manager, not me personally. If the top end looks naffed, then give it a go replacing, but should only be done after finding the cause of the damage. Try to find a local shop/person that actually know what they're doing, or if you're in Suffolk, come and see me! ☺

Could be a few different things. Pot and piston may not be scored, but remember you can lose compression at the bottom end as well, sounding like a bag of nails could be worn bearings and leaky seals. Best off pressure vacuum testing before taking the pot off. We can all guess, but it's testing that gets the answer right....usually.

Unfortunately, us dealer techs are restricted by huge parts markups and our high labour rate. I've been forced to write off many saws because the cost creeps up to 60-80% of the cost of a brand new saw with hardly no time at all. My company is an agricultural as well as horticultural engineering firm, so you can imagine our labour rates, and I work on everything from tractors to leaf blowers! Dealers often get a bad name, but it's the nature of the market. It's often more economical to have a small independent business work on small kit, as long as they know what they're doing and try to stay updated with current kit.

The error codes in the CST can help to point you in the right direction, but I find the fuel settings info more useful IMO. If you know what the Autotune chip is looking for when it's doing its micro-adjustments, then you can get a snapshot of where going on inside the saw. For example, if it's adding a lot of fuel to compensate for a leaky de-comp valve, (550xp/560xp) then it could be too flooded to start correctly. Just an example. The CST is just another tool in the toolbox, it doesn't replace all the other tools.

Don't mistake a small build-up of fuel vapour in tank after running saw for a while for a vacuum.

An 026 will be getting on a bit now, so there's a chance seals, and rubbery parts will be starting to stiffen and wear a bit. An issue that arises when unit is hot suggests that it's either to do with expansion and contraction. I.e part is fine when cold and contracted, but is failing when heated up and expanding. E.g seals, etc. Or another shot is ignition module failure. When hot, the teeny tiny solder connections in the module move apart and break contact, then re-join when cold. As usual, nothing is certain without seeing the unit.

I do the same with the classic smashed/dropped top-handle, it works out cheaper for the customer in the end.

No, they had the older style flat cover.

I've had to put new cranks in 4 of the earlier ones under warranty. Lately I've had a few of the newer (2015/16) with destroyed bearing cages, however the cranks were not worn.

There are many highly skilled and knowledgable people on this forum who can help with any number of problems, but at the end of the day, you're the one with the actual chainsaw that has a problem. So it boils down to hands and eyes...take it apart and look at it. How does the chain brake function? A band, essentially a big spring, tenses and relaxes, gripping or releasing a clutch drum. So either there's not enough gripping going on or none at all. Check all parts of the system, for wear and contamination, or if any are missing! Swap the side cover or drum with a known good one if you can beg or borrow (not steal) one.

Not really right mentioning names of employers.

On my bench last week was a 346xp that has sat with fuel in it on someone elses bench for a year or two! Carb went through the ultrasonic cleaner 3 times and fitted carb kit in Monday. She runs sweet as ever now, saved the customer £130 for a new carb (yes I work for a dealer!)

No offence taken Spud, perhaps I was a bit defensive. We've all had different experiences, when I sprayed it in small amounts around a Husqy 350 intake it sent me around the houses, yet on the 026 clutch side seal, it was a handy pointer.

I suspect you're correct, there are so many variables with chainsaws, more so than other 2-strokes in my opinion. There's chain, bar, type of wood (or plastic..go figure) being cut, fuel, carb, tank vent, hoses, mating surfaces, gaskets etc. etc. That's why I love em I guess, the challenge. Hope you get to the bottom of your issue.

At the risk of getting shot down in flames by making suggestions, I'll share a few ideas. If the saw is idling, then fuel is reaching the carb, however it might not be getting enough.Take the top cover off and look at the intake area when in the cut, anything out of place? Hoses all intact? You can do quick checks by taking the exhaust off and having a peep at the piston. All quick little visual tests that can save a lot of guess work.