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STIHL The Official Stihl Chainsaws Thread

heimannm

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Customer brought in a MS210C today that I had worked on in November, said he used it a few times and last time it wouldn't start.

"When did you try to start it"

"Yesterday, not even a pop"

Choke off, throttle pinned open, popped on the first pull, sputtered on the second, ran on the third.

Mark
 

Woodwackr

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Customer brought in a MS210C today that I had worked on in November, said he used it a few times and last time it wouldn't start.

"When did you try to start it"

"Yesterday, not even a pop"

Choke off, throttle pinned open, popped on the first pull, sputtered on the second, ran on the third.

Mark
🙄
Did you charge him the full diagnostic fee? 🤣
 

heimannm

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Another one dropped off yesterday, MS251, wouldn't start.

Tried a few pulls with throttle open, nothing.

Removed the top cover (only one screw...) and tried it again, saw the choke rod flopping around loose. Connected the choke rod, set the choke, started on the next pull.

Sharpened the chain and sent him on his way.

Mark
 

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Another one dropped off yesterday, MS251, wouldn't start.

Tried a few pulls with throttle open, nothing.

Removed the top cover (only one screw...) and tried it again, saw the choke rod flopping around loose. Connected the choke rod, set the choke, started on the next pull.

Sharpened the chain and sent him on his way.

Mark
Easy money, lol
 

eric4

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I've got a 400c on my bench right now, that fires right up but runs at a wicked fast idle... Checked the piston and cylinder, and they look great.

I'm worried to try reprograming the m-tronic, if it's an air leak or fueling issue, so maybe a solenoid/filter replacement should be done first?

Is it common for a 400c to develop an air leak, around the intake boot perhaps?
 

hacskaroly

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that fires right up but runs at a wicked fast idle
Try spraying brake cleaner (non flammable) around both oil seal areas and the intake boot. If there is an air-leak it will suck in the spray and cause the saw to turn off. If it does that then you will have a good idea about an air leak and location. I would say that the fuel filter is not an issue, if it is racing, it is getting plenty of fuel. How does the air filter look? I wonder if whoever was running it was running with a really dirty filter and through running the mTronics adjusted for it as best as possible and if they changed to a clean filter, the mTronics may not have adjusted back. At this point it might be worth running through the reset.
 

eric4

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Try spraying brake cleaner (non flammable) around both oil seal areas and the intake boot. If there is an air-leak it will suck in the spray and cause the saw to turn off. If it does that then you will have a good idea about an air leak and location. I would say that the fuel filter is not an issue, if it is racing, it is getting plenty of fuel. How does the air filter look? I wonder if whoever was running it was running with a really dirty filter and through running the mTronics adjusted for it as best as possible and if they changed to a clean filter, the mTronics may not have adjusted back. At this point it might be worth running through the reset.

Ok thanks for the advice! I am not too familiar with m-tronic saws, so this is new terrain.

I'll try the brake clean test first, and then attempt a re-tune. It was sold as good and running, so maybe it's just running improperly due to differences in fuel and tuning location/environment.
 

hacskaroly

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I'll try the brake clean test first, and then attempt a re-tune.
Luckily the retune run isn't that long, not like you have to run it pegged for 20 minutes...its pretty quick to go through the cycles.

That's a good tip about the non-flammable brake cleaner, I'll have to remember that.
Yeah, some people like to use ether or other flammable products which cause the saw to race (running really lean), but without the added benefit of having lubricant. I had a guy that had been running his 066 and it was dirty after using it, so he used ether to try to get the crap and pine sap off while the saw was still hot...caught the saw on fire, melted most of the plastic and rubber parts. Sad day.
 
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