ms200t maybe carb problem?

[Lively]

I have a ms200t that revs up fine and works perfect apart from when its idling, it idles fine unless its moving about then it revs up and down a little bit, carb looks fine in my eyes cant see anything wrong with it and adjusting the carb doesnt help, any ideas?

[Rich2484]

Where to start.....

 

How are you adjusting the carb.

 

Is there a sponge type filter behind the air filter under the inlet port.

 

Is the comp good.

 

Is the plug a good colour.

[mikerecike]

something is loose I'd guess letting air in - all screwed and bolted down properly? - crank seal leakijng air? have you pressure tested the fuel line - sometimes a crack only opens when twisted one way? sure there's enough petrol in there covering the pickup?

[spudulike]

Sounds like it may be a dodgy crank seal, what age is the saw and what sort of use has it had - and I don't mean "I have used it for cutting wood":001_rolleyes:

 

If the idle fluctuated with the saw just sitting on the deck then I would say typical carb problems but the moving thing makes me think crank seal or fuel pipe/impulse line related.

 

Try moving it from side to side so the clutch cover and recoil cover are parallel with the deck and see if that does anything but DONT hold the saw with the top handle.

 

Then try moving the top handle about with it sitting normally on the ground.

 

Let me know if one, the other or both make the saw play up.

[mixedangased]

check the inlet manifold for splits,has it been dropped ?

[Lively]

the saw is about 7 years old with nearly everyday use, i took the carb and handle off and relieased the manifold was nearly ripped off completely, replaced it from an old breaker 200t and works like new, cheers guys, no its not been dropped just very old.