SRM225, runs fine, then not

PTmowerMech

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New NGK BPM8Y plug, fuel line, filter and cleaned the spark arrestor. Had to removed the little plugs in the carb so I could adjust it. Got it started, adjusted it what I think is spot on. It idled pretty smooth, had lot of power on the WOT. Let it sit for about 10 minutes and it fired right up, without the choke.
Let it set about an hour and it's right back to trying to start, but just won't. Almost every pull, I get a little something, like it's gonna start. Like a "hubba hubba" sound. With the choke on or off. With throttle pulled or not.
It almost sounds like the timing is off or it floods easily. But this is the 2nd time this has done this. And once it does start, it runs and idles great.

Plug is wet.

Any advice would be appreciated.
 

Hammermechanicman

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You need to do a pressure test on the carb. See if the metering needle is leaking down. Clue, you had to adjust the carb to run good. If tank is pressurizing and saw sits and needle very slowly leaks down it can cause flooding. Try running saw then shutting it off, remove and replace fuel cap and let it set for an hour and try to start it.
 

PTmowerMech

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You need to do a pressure test on the carb. See if the metering needle is leaking down. Clue, you had to adjust the carb to run good. If tank is pressurizing and saw sits and needle very slowly leaks down it can cause flooding. Try running saw then shutting it off, remove and replace fuel cap and let it set for an hour and try to start it.

It held 7lbs for the 5 minutes I pressure tested it.

Also something I noticed, nothing really changes now about the L side. It idles fine, even when it's completely closed.
 

Hammermechanicman

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It held 7lbs for the 5 minutes I pressure tested it.

Also something I noticed, nothing really changes now about the L side. It idles fine, even when it's completely closed.
You got a carb problem. Check valve or metering needle most likely.
 

Mower King

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It held 7lbs for the 5 minutes I pressure tested it.

Also something I noticed, nothing really changes now about the L side. It idles fine, even when it's completely closed.
Those carbs are SOOOO hard to get just right! I quit screwing with them and just get an O.E.M. replacement carb, less headache and they always work well.....so far!
 

PTmowerMech

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Those carbs are SOOOO hard to get just right! I quit screwing with them and just get an O.E.M. replacement carb, less headache and they always work well.....so far!


I got the carb in yesterday. But before I put it on, I thought I'd crank it up and see what it was doing again. (it's been a week or so since I've messed with it).

Darn thing fired right up, tuned right up. And ran like a champ for about 20 minutes. So now I've got a new carb for it, but no reason to install it.

Things that make you go hmmm.
 

StarTech

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So you did remove both EPA plugs on that rotary carburetor? Sometime high speed needle needs to be removed and cleaned as it has a tiny center metering port. Low speed is the hardest to get the EPA plug ; unless, you got the extraction tools. 2.5 mm and 3 mm ones. The 3 mm is for those plugs that someone F'd up.
 
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