Stihl 025 no spark

[cuerno]

I had not used this saw in over a year, so I clean it up and made some fresh fuel and it started up and I made about ten cuts on a large limb. The next day it would run for no more than 5 seconds and when I did get it running alot of smoke came out underneath, I turned it off and waited the next day to try again but this time I'm geting NO spark. I removed the spark plug from the engine and reconnected plug to the wire and grounded the plug to the engine metal, pulled the starter rope but no spark. I tryed it in choke and run position, brake on and off but no spark with plug grounded. Did I burn up my brake system or the coil went bad??? It has a new plug, new fuel filter, new air filter...

 

[cuerno]

up date

I did a compression check and got 120. I do have spark now but still no start up, will take the carb apart tomorrow and try again, still wondering about the smoke but it didn't have a smell to it...

 

[Saw Dr.]

You tell us if you burned up the brake. If it got hot enough to fry the brake, you could have melted the crank seal a little also. Did the smoke smell like burning plastic, burning metal, or burning oil?

 

[cuerno]

it smoked for about 3 second but no smell. and it has 120 lbs per sq. in. of compression after the smoke issue. I'm going to do a carb break down in the morning.

 

[cuerno]

update II

I took the carburator apart and then put it back together and still no start, so I removed the muffler to see if it could start without any restriction, but no start. Then I happen to look in the exhaust hole and I saw about a teaspoon full of fuel in the cylinder, I tilted the saw every way possible but the fuel didn't come out so I used a paper towel. I guess I have a flooding issue but you would think after taking the spark plug off about 4 times it would have dry-ed on it own, I'm wondering now if fuel leaks down pass the rings could I have a crankcase full of fuel or is there enough gap for the fuel to leak out of the saw at the bottom?? Do I have a bomb here? XDo I need to break down this thing completely??

 

[cuerno]

update III

Well it didn't blow up but started up and after adjusting the mixture its running good. So we had a one time flooding issue that first had me thinking bad coil,

 

[babaoriley]

Poor thing, talked to himself most of the time. I have a 025 with similar problem, changed the coil, it started and ran great for a couple days now back to no spark. I cleaned the flywheel and the coil, still no spark.

 

[babaoriley]

I don’t get this saw at all. It ran when it wanted too. And now definitely doesn’t wanna run. I checked every point, they’re all good. I have 3 ignition coils that I swapped back and forth just so I’m sure that’s not the problem. The flywheel looks good and all, why there is no spark still?

 

[lone wolf]

I don’t get this saw at all. It ran when it wanted too. And now definitely doesn’t wanna run. I checked every point, they’re all good. I have 3 ignition coils that I swapped back and forth just so I’m sure that’s not the problem. The flywheel looks good and all, why there is no spark still?

Flywheel could look good and be bad, I suppose! Swap it!

 

[babaoriley]

Will do lonewolf, I picked up a red lever 025 the other day, cleaned the carb and tuned it back to factory. It’s a little monster compared to this handicapped one.

 

[babaoriley]

How can the flywheel be bad though? It’s a solid piece of aluminum, what could be wrong?

 

[lone wolf]

How can the flywheel be bad though? It’s a solid piece of aluminum, what could be wrong?

I can tell you from my own experience it can, try it! I guess you already took the kill wire off right?

 

[babaoriley]

I can tell you from my own experience it can, try it! I guess you already took the kill wire off right?

No. Everything is still intact.

 

[babaoriley]

Red lever 025 and normal 025 both running earlier today.
View attachment IMG_0985.mov

 

[lone wolf]

No. Everything is still intact.

Take the kill wire off the coil.

 

[Brushwacker]

Does the wire go behind the carb? Maybe it got pinched.
I have lotta hours behind 025 s and very rarely an issue.

 

[babaoriley]

Take the kill wire off the coil.

What’s the purpose? If the saw runs then what’s next?

 

[babaoriley]

Does the wire go behind the carb? Maybe it got pinched.
I have lotta hours behind 025 s and very rarely an issue.

Will check it tomorrow, thanks!

 

[babaoriley]

Take the kill wire off the coil.

Just did and the saw runs well, I had to dump the fuel out to shut it off lol so next move is to check the kill wire?

 

[lone wolf]

Just did and the saw runs well, I had to dump the fuel out to shut it off lol so next move is to check the kill wire?

I would check the switch with an OHM meter, then look for frays in the wire where it can short to ground also. Its either one of these!