bmp01

The oil pump on a saw is a fairly simple device but also a fairly pathetic vacuum device. You've seen you can suck oil through the lines with a proper vacuum pump but don't expect the pump to achieve anything like that sort of vacuum. The reason the pump falls over as soon as it is asked to pull a vacuum is because it will find it easier to suck in air past the seal....and often there is no seal, it relys on a good fit between the oil pump shaft and the housing. With time and wear this clearance increases such that the pump can't pump anything before it sucks air in preference - ie. worn out. Another possibility - the pump shaft is not travelling its full stroke. Maybe gummed up or the return spring might be weak, maybe damaged or even rusted away if it's been in contact with water. I'd pull the pump apart and have a look for wear and / or scoring. See what you can learn. It's unlikely to get any better with time .... BMP01

Length of bar might be an issue but only if your using the full length of bar. If it's a 10" diameter log, I can't see the bar length makes any difference. Assuming the engine speed is not being dragged down near to stalling, then I'd guess the clutch needs a good clean out. Some of these saws can get a bit oily or maybe the clutch bearing has had a dob too much grease in the past. The 181 uses the same clutch as the bigger 211 - assuming genuine parts. BMP01

This. Beat me to it.

It's on the floor, pict 3, just to the right of the gob. But the gob doesn't look like a big enough angle so what you say might still have happened. ...

Dunno if this helps. .. I've never tried this starter cord compression test. My 028 has 155psi after 10 pulls, using an old fashioned "pencil" compression tester (looks like the extending tyre pressure testers but it has a one way valve in there and is rated for cylinder pressures). Anyway, no long tube prior to the one way valve which should avoid low readings. Drop test - the 028 weighs 7 kg with bar and chain and takes appox 20 seconds to get to the end of the starter cord, 3 or 4 revoulutions (each compression event is very obvious). In hind I might have done this wrong? I held the saw in the air and dropped it while holding the cord. It slowed down more and more with each subsequent revolution so by the final compression event it nearly stopped. Didnt attempt to build up any pressure at start... 20 seconds feels like forever by the way, definitely need to do the "1 Mississippi, 2 Mississippi,.....etc" thing And a bit disappointed with only 155 psi, this saw has had new Caber rings and has been squished to 20 thou. But then again it is an old saw design and the combustion chamber is probably a bit big compared to modern saws... runs fine, good torque.

On a sample of one.... bag of excrement. Golf piston for a Husky 136 (so a low value engine), the inside forging was 1 mm offset to the machined detail, so one wide boss and one narrow boss for the gudgeon pin to run in, off setting the rod to one side. The piston was also 8 grams heavier than the original (thats 48 grams instead of 40, 20% heavier). The gudgeon pin, the hole was visually eccentric and not parallel to the outside diameter. Don't know about durability, this particular one was not fitted. Avoid fitting to anything you remotely value. All IMHO based on a single piston, purchased through that auction site from a dealer, came in manufacturers packaging.

+ 1

Have a look at my post in your other thread ..... I suspect you are going to find the same thing in due course. Or you could bite the bullet and overhaul the carb and fuel lines now. The trouble is you can chase your tail backwards and forwards ad-infinitum - if bits of the system are misbehaving.

...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.