I rebuilt my ms650 new rings piston and head .It start up but won't rev up I bought a new carb and still the same problem no rev up and spitting gas.Thought it was the timing so I changed the key on the flywheel.I checked the spark screen and that's clean even ran it without the muffler all can out with the same result starts up idol no rev up and spitting gas.
Chainsaw
- Thread starter Flip1860
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Spitting gas out of the muffler?
to me it sounds like your running rich (too much fuel)
if your not comfortable tuning (and risking ruining a saw) take it to a shop, and have them tune it, should run right afterwards
if not, I dont know what to tell ya
if your not comfortable tuning (and risking ruining a saw) take it to a shop, and have them tune it, should run right afterwards
if not, I dont know what to tell ya
It's doing the same thing with the new carburator I was of the impression that it comes factory tuned (set)
cuinrearview
Red saw lover
The factory cannot tune a carb for any local conditions where it may be sent to.
it should come close if its OEM and has the limiter caps
check your fuel filter, if it came off the saw will run like crap
check your fuel filter, if it came off the saw will run like crap
If you can swap a carb, you can definitely tune one.
Sounds like either bad carb tuning or incomplete combustion to me. A new carb "shouldn't" be set that rich from the factory, but who knows.
I'd change the spark plug (ideally for a known good one, if you have another saw that takes the same plug), and tune the carb.
Sounds like either bad carb tuning or incomplete combustion to me. A new carb "shouldn't" be set that rich from the factory, but who knows.
I'd change the spark plug (ideally for a known good one, if you have another saw that takes the same plug), and tune the carb.
I just about change everything plug carb fuel filter piston rings and head I even changed the coil the saw runs but will not rev up just spits out the fuel threw the carb and now the muffler.Can this happen if the rings shifted from the Lock position and is not seating properly just a thought
If the rings shifted & you somehow managed to get it together you'd have a broken ring. What's the compression like?
Where did your cylinder kit come from? I think you might be getting to the point of pulling it apart & looking for damage or a defect
Aftermarket parts or OEM?
You did not say if the parts were China crap? I'm guessing they might be! Not easy without info.
Oh it's aftermarket I guess that's where it's from but the thing is when the saw got damaged I just replaced the piston and rings the original head was good and it was the same problem so I decided to change everything still the same the only thing I can think of if too much air is comming from the crankcase hose leading to the carb and blowing the excess fuel don't know is that makes any sence
So Vac and pressure test it next.
How confident are you in you compression tester?
If the dimensions of the piston are off or a window or the skirt is damaged it's possible that could cause the blowback, as could a substantial air leak which is probably the more likely.
The impulse can't really do that unless there is something horrendously wrong with the carb (which you have already changed)
I agree with Lone Wolf, next step is a pressure/vac test. This should be done as a matter of course after a saw has been apart anyway, especially if there was the possibility of an air leak in the first place (ie scored piston/cylinder)
