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...turn it OUT just a touch.... ? Better pick up if it's a tiny bit rich. Nice ' how to' though.

Pretty old saw. There comes a time when is not worth the effort to keep 'em running unless you have a desire to do that sort of thing. My 009 has been on loan and been a compete pain in the back side, wouldn't start from cold and then when finally going you darn't stop it. If it ever ran out of fuel... that was the end of the day as far as that saw was concerned. But then we discovered as old as the saw was, it had one of the modern day disaster features - a carburetor with accelerator circuit (to chuck in more fueling during engine acceleration). It's a disaster feature because it wears out, rendering the carburetor next to useless. With that fixed, it was possible to tune the thing and it became reliable to start hot or cold. I guess it all depends on the condition of the saw - even an old one with low miles is worth fixing up but only you know whether that's what you've got or if it's a beaten up wreck. And probably best to learn how they work coz most repair bills wont make it an economic proposition.

Ah, yes, let me explain - they are the special ones that go ' SNAP' as they slip off the really stiff chain brake springs ..... damned auto correct. .....

Easy, quick job - assuming the springs are just weak, and no subsequent damage to fix broken pieces. There are different spring arrangements from different manufacturers - for the MS260 there are 3 little springs holding the 3 weights together. It'll be quite obvious once you've taken the clutch drum off, so, chain cover off, bar and chain off, ping the circlip off the crank, remove washer and clutch drum and the bearing. Don't lose that circlip. Remove and replace each spring in turn, you do need to do all three. Long noise pliers or even better rounded noise pliers to avoid scratching the spring ... but they are pretty tough little beggars so just go for it. HTH.

It'll be something to do with fuel system and it being bounced about on its travels, maybe it's sitting on its side in the car / van? I bet its sat on its base and left for a bit when it gets home.... Or maybe you're grumpy with it at home and pull the cord a bit harder Good luck, be interesting to know what you find.

As Eric suggests not likely to be a worn cylinder, the metal plating on the inside of the cylinder is very hard wearing. Usually any wear is limited to the piston rings and piston. Probably the test they did in the shop was a compression test - it just tells you how much gas leaks part the piston assembly. From the outside there's no way of knowing which aspect of the piston assembly is responsible. Could be just the piston rings stuck ring grooves though to piston assy and cylinder repacement if its been seized... If the shop pulled the exhaust off (to inspect the piston through the exhaust port) then maybe they diagnosed a seized piston but usually that results in an engine that doesn't run at all, not running problems. Take the exhaust off have a look for your self.... just 2 torx screws and 5 mins.

That a stihl piston? Looks like it, you can just see an 'S' in a box on the top face, near the seized area, second picture down.... That looks like a good one, never fails to amaze me how bad the seizure can be and yet the cylinder can be rescued. On the piston, I think that's 'just' a melted or vaporised surface - i bet the inside of the exhaust is grey too. Do you get the feeling the aluminium is actually burning during the melt down You think it's failed twice then Spud? Guess you'll be looking for a reason then. ...

That's a bit of a shame not to get to that sooner but nevertheless a good result. I've had the same issue with these small plugs, insulation cracked, arcing happened inside the plug, not across the electrodes. Never seen a bad std sized plug. I've posted about this before, can't remember when so I'll add the picture again here. Edit: the black lines across the ceramic are the arcing lines. ..

Damn, now I KNOW I'm getting old. ... I'm being over taken by technology (again), only seen and worked on 'old fashioned' carbs myself.

I expect the pump itself will be fine, it probably won't notice the change. If it has a plastic drive gear that might be an area of concern - but given an oil pump can usually tolerate a small amount of wood dust (oil filters are more like rock catchers than filters, ie crap) then I'd expect that would be fine too.

Stihl 028 Woodboss from Bedford auction for 40 quid, 1995'ish. Chain was hanging off, bar knackered. ...non runner, bag of bits. Didn't know the first thing about saws but luckily it was complete and engine was sound. Cost more in parts to bring it back to working order but still got it and it's a good saw.

Yes, it could be. But have you considered the obvious? Is the clutch spring weak, causing the clutch weights to expand / engage the clutch drum at a to low speed ?

Or the intake boot thingee (between carb and engine) or impulse line. Fuel line could have been tugged if the weight of fuel filter got thrown about. ..

We're obviously trolling round in the same circles - parts diagrams seem easier to come by, actual parts less so, compared to Stihl. I'll give the local dealer a try. ...

I believe we are in agreement, along with the OP ..... Edit: measured my much used depth gauge - like 0.6mm, little wear despite the use. But i think a much more relevant measurement would be to measure the raker depths of the sharpened chain (not the gauge).... which I've yet to do.

Where are you buying your Husky parts, are you buying online or local dealer? Reason for the question - I've had all my Stihl parts from L & S Engineering online, can't find equivalent Husky supplier. ...

Depends what you mean by "an issue" i suppose. I thought the OP had simply made an observation and took the time to investigate it. Results shared on here. Nowt wrong with that. And if after 37 years of sharpening chains he spots an improvement that can give him a better chain - even though he was happy with previous chains, that's no bad thing either. I have always blindly used the depth gauge to set rakers but i don't really know what depth they are at. ... might be some room for improvement. Just my 2 pence worth.

It's actually pretty good isn't it. If you have the time and a carb on the bench it will teach you how the carb is supposed to work but watch out for a few variations on the general theme. Can't remember, does it have the good old acceleration jet circuit in there too?

Not looked into it in any great depth, but similar to you I had been using a Stihl depth gauge and moved on to Oregon (new chain maintenance kit) and noticed the Oregon depth gauge was suggesting I file more off of the rakers. ... I didn't follow it up to find out which was in error. Might be worth a measure of a new chain, although i guess there is no guarantee that is correct.

Emissions are worse, assuming all other running conditions are the same. ... Fundamentally, the manufacturers were forced by legislation to improve on emissions - so the first thing they did was to make the exit hole in the exhaust smaller. That works by increasing the back pressure on the engine, forcing some of the unburnt fuel and air back into the engine, reduced emissions but also reduced performance. So guess what the first step of tuning is ?? Ok, so thats a very general comment and primarily applies to older generation (pre strato saws) but it is still true to a lesser extent on more modern saws. Other aspects of tuning that improve combustion can reduce emissions - as simple as tuning the carb properly or more complicated an increase in compression ratio, spark advance. Porting changes including port timing - in general will increase gas flow through the engine, most likely to increase emissions .... I'd wager any one interested in getting more from a saw is also likely to maintain it and keep it running properly which in itself will reduce emissions. ...

Link to Rob's You Tube on this. (If it works ! ? !) https://www.google.co.uk/url?sa=t&source=web&rct=j&url=https://www.youtube.com/watch%3Fv%3DV7P-jyBgu_Q&ved=0ahUKEwirsuiGlqDYAhXPFsAKHTzTBUoQwqsBCE4wBg&usg=AOvVaw3g5KyRz7d8iLIut2wDCuip

Trouble is lots of stuff gets sold when there are problems. Sure there are a few genuine "got no use for it" or "need the money" type sales but there are very few real bargains because the value is so easy to establish with the Internet. Plenty of stolen goods too i guess but i digress. Caution is the order of the day which you clearly know. Personally I'm never happy with a used saw until I've found (and fixed) a few problems, in the hope that was why it was up for sale. .... Twisted logic

Nope..... not a chance. .....

Yes, well, that's the same the world over. But my point: 181 is basically a 171 with a tiny bit bigger piston (same stroke). If a clapped out 171 out cuts a 170 then a 181 will too. The 211 is the one to have though in this class of saw, biggest engine in the same saw frame.

Something not right with the 181 then. A bit of a coincidence - i was checking a rebuilt 171 today. Needed a bar and chain so i borrowed the one off my 170, and took the chance to compare the two saws. The 171 has a misfire at peek rpm, coil i think, but it was still quicker in the cut than the 170. Wood varied in sized but upto 10 ", same bar and chain. A 181 should be a step forward.