Stihl 441 CM won’t start when hot.

[Squatch]

Title says it all. Mtronic carb. Anyone ever had this issue? How’d you correct it? Looking for suggestions.

 

[Fatherwheels]

Title says it all. Mtronic carb. Anyone ever had this issue? How’d you correct it? Looking for suggestions.

Take off the muffler and look to see if the piston and cylinder are ok, you need to be sure of this before you
start replacing parts elsewhere.
You could also take off the fuel cap in case the vent is not working, do this with the saw on its side, then replace the cap and see if it starts.

Were you working in very high temperatures, is a vapor lock possible, did you take out the plug to see if its wet when the issue arises.
All I know is the MT saws solenoid go into open mode when they fail, in other words they flood the engine and that will cause a no start.
Maybe hold the throttle full open as you try to start the saw, see if that helps when its hot.

 

[Squatch]

Take off the muffler and look to see if the piston and cylinder are ok, you need to be sure of this before you
start replacing parts elsewhere.
You could also take off the fuel cap in case the vent is not working, do this with the saw on its side, then replace the cap and see if it starts.

Were you working in very high temperatures, is a vapor lock possible, did you take out the plug to see if its wet when the issue arises.
All I know is the MT saws solenoid go into open mode when they fail, in other words they flood the engine and that will cause a no start.
Maybe hold the throttle full open as you try to start the saw, see if that helps when its hot.

I would be shocked if it was the cylinder. I’ve taken extremely good care of it, and power / compression is good. Maybe the solenoid. I’m working in high temp and high altitude 85 - 110 and 5,500’+ . I did remove the fuel cap and held full throttle. After removing the cap I can get it to pop, but then it quickly dies.
It fires right up when cold. Yesterday I was cutting firewood. It fired right up I cut 9 or so rounds. Sat it down to split some and toss in my truck. Then when I went to cut again I couldn’t get it started. This is like the 4th time it’s happened to me.

 

[Fatherwheels]

I would be shocked if it was the cylinder. I’ve taken extremely good care of it, and power / compression is good. Maybe the solenoid. I’m working in high temp and high altitude 85 - 110 and 5,500’+ . I did remove the fuel cap and held full throttle. After removing the cap I can get it to pop, but then it quickly dies.
It fires right up when cold. Yesterday I was cutting firewood. It fired right up I cut 9 or so rounds. Sat it down to split some and toss in my truck. Then when I went to cut again I couldn’t get it started. This is like the 4th time it’s happened to me.

I would have thought the MT system would have no issue with altitude, fuel solenoid could be the problem. What color is the Solenoid in your saw,
what age is the saw, I think the newer white solenoid is less problematic, you may need to take it to Stihl and have it put on the computer.

I can tell you one thing, leaving a saw in the heat for fifteen minutes can cause the fuel in the tank to get pushed into the engine, I left my fuel
can in the sun and it looked like a ball when I went back for it, that kind of pressure could cause plenty of trouble.

 

[Squatch]

It is a newer 441. Bought in 2018. I will need to check on the solenoid color.
I live in the southwest Sierra mountains and cut anywhere from 2500’ of elevation up to 7500 - 8000’ which is why MT appealed to me.