Bernie’s MS250 Upgrade

[lehman live edge slab]

Did you unhook the wires and try cranking it just to be sure a wire isn’t rubbed or the metal ground strap on the switch isn’t messed up. I had a 250 the wire was rubbed and grounding on the block

 

[Paul Fithian]

Yes, I looked that over real close. All of the wiring looks factory perfect and unmolested. If there was a short in the wiring, it should have shown similar resistance when the coil was disconnected, right? Looks like there is a weak connection inside the coil.

Bernie did mention that it was getting harder to start as it got older.

New coil ordered for the fix.

 

[Loony661]

Yes, I looked that over real close. All of the wiring looks factory perfect and unmolested. If there was a short in the wiring, it should have shown similar resistance when the coil was disconnected, right? Looks like there is a weak connection inside the coil.

Bernie did mention that it was getting harder to start as it got older.

New coil ordered for the fix.

I would check Ohm resistance on each wire individually to be sure you don’t have a broken wire. Although rare, I have had it happen to me on a saw.. Disconnect each wire from both ends and check resistance with your meter.

 

[lehman live edge slab]

Yes, I looked that over real close. All of the wiring looks factory perfect and unmolested. If there was a short in the wiring, it should have shown similar resistance when the coil was disconnected, right? Looks like there is a weak connection inside the coil.

Bernie did mention that it was getting harder to start as it got older.

New coil ordered for the fix.

Ok, new oem coil or aftermarket?

 

[Woodpecker]

What’s the spark look like? I may have missed it but did you check?

 

[Paul Fithian]

What’s the spark look like? I may have missed it but did you check?

No spark, even when black wire terminal removed from coil. Farmertec coil ordered.

 

[Loony661]

No spark, even when black wire terminal removed from coil. Farmertec coil ordered.

Did you Ohm test the spark plug to see if the plug itself is bad? I’m being serious.

 

[Paul Fithian]

Tried 2 different plugs, one that was previously used in another 024.

 

[Loony661]

Tried 2 different plugs, one that was previously used in another 024.

Swapnostics works too.

 

[Paul Fithian]

Happy to report saw runs perfect after installation of a Walbro WT-215-1:




Old vs new carbs:



Put the OEM Stihl coil back in and sharpened both of his chains.

Runs, handles, and cuts great, these are nice light saws. Feels more nimble than an 024/026 model.

 

[Paul Fithian]

Bernie dropped his saw off the other day, and said the new maintenance guy at his shop tried to run it and it would not go above idle. On the bench I found this:


Center post on the hand guard was broken off and it was jammed on the muffler in the forward position, locking the brake. No other damage, this numbskull used about 1/2 tank of fuel and there were saw chips/dust all over it. For sure he had cut a fair amount of wood with it, but told Bernie it was like that when he grabbed it from the bench and didn't cut with it.

Found a used Stihl part on eBay and put it on, all good:


Original and replacement had the same part number, but they are different designs and came from different molds: