Stihl 025 has me stumped

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I worked on an old saw of that series last year, the flywheel key was sheared, so I grabbed another junk saw off the shelf and popped on a good flywheel, the saw wouldn't even pop. I tried a few other coils, still nothing. I finally put
back on the original flywheel and coil, lined up the key, zipped it down with an impact wrench. It fired right up.
The flywheel part number was different, and, no, I didn't write it down. The guy was in a hurry.
 
In fact, media cat only shows one coil for the 021,023,025,210,230,250 all the same coil and flywheel unless it's the easy start, that's the only one that is different, and if it were an easy start flywheel, you'd never get an 025 recoil over the flywheel.
 
I build kits and your problem may lie in what you said. Its all new, I see it often in what i do. As harley mentioned your old parts you might backup and try your original coil if it was oem, i guess you checked your magnets on the new flywheel?
 
In fact, media cat only shows one coil for the 021,023,025,210,230,250 all the same coil and flywheel unless it's the easy start, that's the only one that is different, and if it were an easy start flywheel, you'd never get an 025 recoil over the flywheel.
easy start has the pawls on the flywheel on the 250. flywheels have two magnets and a builtin keyway in the two i have seen. One oem and one a copy. the ipl is current.

ms250 flywheel.JPG ms250 flywheel 2.JPG
 
Found this online. Same page as Obama's birth certificate....

View attachment 608691

Correct, there are multiple flywheel revisions, but there is only one coil number, so all the flywheels used the same coil. Unless it's the easy start that uses a thicker flywheel. What I'm trying to say is there isn't multiple coil/flywheel combinations that have to mate up like the 066 model nightmare.
 
easy start has the pawls on the flywheel on the 250. flywheels have two magnets and a builtin keyway in the two i have seen. One oem and one a copy. the ipl is current.

View attachment 608692 View attachment 608693

I understand the flywheel differences between the easy start and non, but if you have an easy start flywheel on the saw, a non easy start recoil will not physically fit over the flywheel.
 
I think your saw is severely flooded, I've seen this exact issue when I had an arrestor screen plugged solid on an 025. Took air cleaner off, held saw upside down with throttle held wide open and gas ran out of carb.

Hdtoolmkr765, you are the winner! The latest posts tell me the coil and flywheel are matched. I bought an inline spark tester on the way home tonight and , as expected, lots of spark. Opened it up and tipped it upside down and as you suggest, some gas poured out. I put the 18 year old original plug back in and it fired. Yay!

Adjusted the carb and its running pretty good now. I've been a hobby mechanic for 30 years and have worked on all kinds of 2 strokes but have never seen this exact problem. Usually a dry plug in a flooded engine will give some sort of feeble pop at first. Now I know - thanks for all your kind help and prompt answers.
 
Hdtoolmkr765, you are the winner! The latest posts tell me the coil and flywheel are matched. I bought an inline spark tester on the way home tonight and , as expected, lots of spark. Opened it up and tipped it upside down and as you suggest, some gas poured out. I put the 18 year old original plug back in and it fired. Yay!

Adjusted the carb and its running pretty good now. I've been a hobby mechanic for 30 years and have worked on all kinds of 2 strokes but have never seen this exact problem. Usually a dry plug in a flooded engine will give some sort of feeble pop at first. Now I know - thanks for all your kind help and prompt answers.

Glad you got her running, it still cracks me up how you can have fuel and spark and not get it to cough, but for some reason, severely flooded ones just won't fire sometimes. I've been around a saw or two, glad I could help.
 
I understand the flywheel differences between the easy start and non, but if you have an easy start flywheel on the saw, a non easy start recoil will not physically fit over the flywheel.
I was just giving you the differences. I had the ipl. It's great it's running. Whole point.
 

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