MS290 giving me fits

[dallypost]

I have an MS290 that is giving me trouble.

Last year it stopped running so I
1. Put a carb kit in it
2. replaced the fuel filter
3. replaced the fuel line
4 replaced the spark plug

It ran good after this work

Now, it starts easy and runs strong for about ten minutes. Then it starts to bog on accelleration and does not want to idle. A few minutes later, the RPM at full throttle begins to surge up and down. After that, give it up because no new work will be accomplished.

I just cleaned the air filter and retuned the carb. It fired right up and repeated the above problems. I tune as follows:
1. H and L one turn out
2. LA up until it wants to crab the clutch
3. L in until it starts to die then back one half turn
4. H out until it starts to burble pretty good at full throttle

Any suggestions

Lance

 

[fearofpavement]

How long did the saw sit since you used it last? You may need to go back through the carb.

 

[w8ye]

Something is opening up a air leak when it gets hot?

Might be seals?

 

[biggus]

Not sure where the fuel vent is on the 290 but maybe that's the culprit - when it starts to bog down you can turn the unit (as to not spill gas ) and loosen the gas cap and see if performance cleans up. Also check the spark screen @ muffler and make sure it's free of crud - these are both simple and free checks then if you have the equipment pressure and vacuum test for seal failures. But for things like this I would second the carb. Always a good place to start.

 

[Somesawguy]

I'll second the fuel tank vent. Open the cap, and see if the problem temporarily goes away.

 

[biggus]

speaking of which... there it be...





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