066 stopping when wormed up

[chevy]

I was looking at a friends o66 and it runs good untill it warms up.After it gets warm it will stop and wont start untill cold agin. Any idaes what it wight be??

 

[Maui Palm & Tree Care]

piston rings could be shot. when an engine is cool the metal expands and when it gets hot it shrinks. so when the rings are cold there is good compression and runs until it gets warmed up then it looses all the gases to make a combustion chamber work. how is the idle speed? is it jerky or smooth? could be running lean too. does it bog down in the cut? does it stall when you rev the trigger?

 

[Jeff_Cochran]

when an engine is cool the metal expands and when it gets hot it shrinks.

you got that backwards but we got the point. merry christmas josh

 

[Winterbush]

check the coil/ magneter thingie.

 

[chevy]

I was thinking rings also. It idles great have not put it in any wood yet. My friend is looking to get rid of the saw and I think I can get it from him for $150. For that price even if I have to put a new top end on it I'm ok with that.

Thanks Guys Merry Christmas!

 

[Treetrim]

[ QUOTE ]
check the coil/ magneter thingie.

[/ QUOTE ]

Thats my bet to it is too. Had a little poulan trim saw do the same thing and new used coil fixed that.

 

[TimberJack]

It might be the crank seals. My 460 was doin the same thing and thats what was wrong.

 

[Maui Palm & Tree Care]

oops sorry bout my reply. had a bit to drink when i posted that. thanks for catching that jeff.

 

[Saw_House]

It sounds more like you might have a compression problem. Have you check for any piston scaring?

The MS 066 has a tendency to over rev, causing scaring when unit has been ran with a dull chain.