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Stihl MS 250's

anderson3754

anderson3754

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Up date..... The new ms 250 now has 3 tanks of fuel through it. Starting procedure is has follows, Full choke pull twice, 1st pull no false start, 2nd pull the false start can barely be heard , but it is there. Move control lever to high idle 1st pull nothing, 2nd pull it starts and runs great. If you leave it on full choke and pull 3 times it's flooded.
The saw runs great 16 inch bar, 3/8 LP full chisel chain, the cuts are smooth and fast.
 
sundance

sundance

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Up date..... The new ms 250 now has 3 tanks of fuel through it. Starting procedure is has follows, Full choke pull twice, 1st pull no false start, 2nd pull the false start can barely be heard , but it is there. Move control lever to high idle 1st pull nothing, 2nd pull it starts and runs great. If you leave it on full choke and pull 3 times it's flooded.
The saw runs great 16 inch bar, 3/8 LP full chisel chain, the cuts are smooth and fast.
Mine is hopelessly flooded at two full choke pulls. Remove plug, turn it over and cycle to clear gas.
I have yet to figure out a reliable starting sequence.
 
HarleyT

HarleyT

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Yes. If I can get it to start I really like the saw. Runs and cuts very well.
Just try starting it with no choke first off.
If it doesn't hit, then try a light pull with the choke on, then follow with several pulls with the choke off, and see what happens.
 
SteveSr

SteveSr

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Getting really tired of it getting so locked up I can't even pull it.
Sounds like you may have a carb needle and seat problem. To prove or disprove this theory perform a pressure test on the fuel inlet to the carb. Carb should hold 7-10 psi indefinitely. If it leaks down you have a direct path for fuel from the tank into the engine i.e. flooding.
 
sundance

sundance

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Sounds like you may have a carb needle and seat problem. To prove or disprove this theory perform a pressure test on the fuel inlet to the carb. Carb should hold 7-10 psi indefinitely. If it leaks down you have a direct path for fuel from the tank into the engine i.e. flooding.
@SteveSr , I don't have equipment for a pressure test. Cheap source? Or a work-around?
 
HarleyT

HarleyT

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SteveSr

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@SteveSr , I don't have equipment for a pressure test. Cheap source? Or a work-around?
You can also use a sports inflator (or bicycle pump) if it has a gauge on it and doesn't leak by itself. You can test it before you buy it by plugging the output hose. Or make one with a few simple parts like Harley shows above.
 
sundance

sundance

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Ordered a Mityvac MV8500. When I found it for about $55 it didn't make sense not to get the additional capability instead of ~$20 in parts.
When it gets here I'll see what it adds to the saga. I like the saw for it's niche when it will start.
 
sundance

sundance

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Just try starting it with no choke first off.
If it doesn't hit, then try a light pull with the choke on, then follow with several pulls with the choke off, and see what happens.
Tried it today, no choke. Started after 6-8 pulls. Reckon this will be my plan until I can pressure test the carb. Depending on that, be curious to see what happens when it gets colder,
 
sundance

sundance

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Depending on the carb model you can probably just put in an OEM kit for considerably less. The only carb that I wouldn't kit would be if it had a fixed "H" jet. Which carb do you have?
To be honest I wasn't smart enough to verify when I was testing. According to the IPL it "should" be a Zama C1Q-S85B.
 
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