Problem with chainsaw

iron man

Well. She starts on the button and revs up no bother. Put her on a piece of timber and she starts to die out. I have taken off the air filter and cleaned it. No good. Any one any suggestions.

CJhaughey

iron man wrote: »

Well. She starts on the button and revs up no bother. Put her on a piece of timber and she starts to die out. I have taken off the air filter and cleaned it. No good. Any one any suggestions.

Sounds like low compression.
Is there many hours on the saw?
Have you checked the Compression with a gauge that has the valve down near the plug?

iron man

No. I have no way of checking the compression. She is a fairly fresh saw. Stil has original chain and bar. Is there any adjustments that can be made to improve its proformance or improve the compression.....

Figerty

iron man wrote: »

Well. She starts on the button and revs up no bother. Put her on a piece of timber and she starts to die out. I have taken off the air filter and cleaned it. No good. Any one any suggestions.

Aside from low compression which is likely, are you using old mix?
Could there be moisture in the petrol mix.
Is the spark plug knackered?
Have you cleared the fuel lines?
Is it starved of fuel?
Is the filiter in the tank clogged?

snowman707

sounds like the carb is off tune

this might help

http://www.youtube.com/watch?v=lDhG0Hk01sc&feature=related

CJhaughey

iron man wrote: »

No. I have no way of checking the compression. She is a fairly fresh saw. Stil has original chain and bar. Is there any adjustments that can be made to improve its proformance or improve the compression.....

What is the saw make and model?
If the compression is down then new piston and rings might solve the problem.
Its not that big a job to replace them but it needs to be done with care.
Does it rev out fully with no load?
I couldn't watch that video for long, that guy has no clue, the chain is hanging off the bar!
Anyone that can't even maintain their chain shouldn't be trying to tell people how to tune their carb.

pakalasa

Sorry to hijack the thread but a simular question. My saw, a Stihl, starts fine from cold, cuts fine, but when I stop it, it is very hard to start again. It seems flooded. I noticed that if I let it idle a while before stopping then it sems to start ok the next time. I wonder is it just running too rich at high revs. I adjusted the Carburetor according to the number of turns of the screws, but no real change.
I agree with you on that guy in the video. He may be right in what he is saying, but running a saw at full revs with only one hand is madness. You should always have two hands on a saw when chain is turning.

iverjohnston

Hi Ironman, what make is your saw? You should ask a few farmers or tree surgeons who they use for tuning and rerpairs. Some guys are better than others. If there is a main dealer for your make of saw, thats a good place to start. Pray to God you haven't bought one of those "no-name" Stihl/Husqvarna look-a-likes being peddled around markets at the moment. Average life time about 2 hours.............
There are lots of instructive videos on www.youtube.com re tuning etc if you fancy having a go yourself. Nigel in Cavan

PS I bought a little Stihl MS170 about a year ago, intending to use it only for light fencing jobs etc., but I find it so handy I would go for it before either a Husqvqrna 61 or a Stihl MS440 I have, for anything except full size trees.

iron man

hi ya lads

she is a stihll.... i looked at the tuning video. and had a go. i have to say she is going really well. its just when i get into timber about 3 inches down the chain stops turning and the saw labours slightly. i might free up for a few turns but then goes back to stopping and labouring. any suggestions????

snowman707

iron man wrote: »

hi ya lads

she is a stihll.... i looked at the tuning video. and had a go. i have to say she is going really well. its just when i get into timber about 3 inches down the chain stops turning and the saw labours slightly. i might free up for a few turns but then goes back to stopping and labouring. any suggestions????

get the saw heated up and try peaking the tuning screw about 1/8 of a turn at a time usually the high it takes time and patience and you do need to have it a full throttle

as mentioned check the fuel filter and air filter and plug

we have a husky and a stihl < i could tune the husky in my sleep but the stihl is a PITA

iverjohnston

Hi Ironman, if the saw only gets into trouble when 3 inches or more into the log, is the bar cutting straight?

Avns1s

iverjohnston wrote: »

Hi Ironman, if the saw only gets into trouble when 3 inches or more into the log, is the bar cutting straight?

I agree. This is more likely a problem with the chain or the bar rather than the engine.

If you had a problem with the compression, then it would likely be very hard to start when hot.

Figerty

snowman707 wrote: »

get the saw heated up and try peaking the tuning screw about 1/8 of a turn at a time usually the high it takes time and patience and you do need to have it a full throttle

as mentioned check the fuel filter and air filter and plug

we have a husky and a stihl < i could tune the husky in my sleep but the stihl is a PITA

Be careful about messing with the tuning settings. If you alter the tuning to make it run cleaner the saw will seize and score. 2 Stroke engines run 'dirty' to maintain lubrication. Leave it to the experts.

CJhaughey

Figerty wrote: »

Be careful about messing with the tuning settings. If you alter the tuning to make it run cleaner the saw will seize and score. 2 Stroke engines run 'dirty' to maintain lubrication. Leave it to the experts.

Its a very fine line between running well and a hot seize, the saw needs to blubber at WOT and run clean under load.
A Tacho is the safest way if you want to find that line.

edanto

Total amateur suggestion here, but if the chain is sticking, would there be an oiling problem? Would that even cause the chain to stick after a few minutes?

CJhaughey

edanto wrote: »

Total amateur suggestion here, but if the chain is sticking, would there be an oiling problem? Would that even cause the chain to stick after a few minutes?

Not unless it was under heavy load, then you might see galling and the bar rails getting blued.
But usually no oil isn't a deal stopper that soon, it shows up as increased wear later.