# 2 stroke is dieseling



## chuck_thehammer (Oct 24, 2007)

Homelite 18 inch chain saw.

cutting down bushes, maybe 20 minutes .... went to stop engine... 

On/Off.. no change.
engine running at 1/2 throttle speed
put chain onto large branch to stall engine .. no good
pulled off spark plug wire.. no change
pulled chock out.. killed engine...

86 degree day and high humidity.
low hours engine.. synthetic oil, 2 month old fuel.
used this fuel 3 days ago in weed cutter.. all good.

carbon from synthetic oil??? just excessive heat.
what caused the dieseling? and Damage????

Open to ideas.... I am a retired auto mechanic.. 
and have rebuilt maybe 20 2 strokes in my life..

other then the dieseling.. engine ran fine and responded to throttle as normal.. just engine would not go below 1/2 throttle speed but carburetor control and shaft did return to idle location.

Have not tried to restart it. 

Thank You for your help.


----------



## 30yearTech (Sep 14, 2006)

Perhaps an air leak causing engine to run hot. 

I can't say I have ever run across this, but then I rarely run equipment long enough to get really hot. 

I have not had this type of issue on any of my personal equipment.

What model chain saw was it?


----------



## chuck_thehammer (Oct 24, 2007)

Thank You 30yearTech.

Homelite UT10848, 27av c/c 18 inch
s/n MB0490437

purchased date 4/27/2000 .. I did not think it was that old. 
price was $179.00 Home Depot.... I keep records and manuals...

I only use it once or twice a year.. some years are not used.. 
only cut down 2 trees with it.. mostly bushes..

tank always emptied. engine run dry.. cylinder oiled before storage.

now thinking parts maybe difficult to locate.
will try to restart today... going to lightly oil cylinder before starting. if overheated.


----------



## chuck_thehammer (Oct 24, 2007)

Strange. refueled it, check plug, ohm the on/off switch and wires....

started up fine... ran fine ... idled normal. 

did not work it... must have been heat... or it wanted to mess with me...

not possible of a fueling issue..

a 1 gallon for pre-mix... 
all others are 5 gallon....

yesterdays work was 20 minutes Max... mostly doing 1 inch or less bushes...

Mystery.. THANK YOU. Mr. 30yearTech.


----------

