Stihl 026 headache

[Dieselcamino]

Hey guys, been busy at work but got back at this weekend, think I may of found the issue but have never seen this problem before.but I'll start with: checked compression, 115 psi all day. Changed crank seals and pressure tested. All good.

What was found was strange, with the spark plug out and plugged in (touching the jug) it won't spark (regardless of the kill switch)
Place some space between the plug and the jug and the spark plug sparks and even arcs to the jug.
Everything looked good, removed the grey wire on the coil and reinstalled it and seems to be good.
I'm lost on this one.

 

[JMCK]

Hey guys, been busy at work but got back at this weekend, think I may of found the issue but have never seen this problem before.but I'll start with: checked compression, 115 psi all day. Changed crank seals and pressure tested. All good.

What was found was strange, with the spark plug out and plugged in (touching the jug) it won't spark (regardless of the kill switch)
Place some space between the plug and the jug and the spark plug sparks and even arcs to the jug.
Everything looked good, removed the grey wire on the coil and reinstalled it and seems to be good.
I'm lost on this one.

Get a good new plug Bosche or ngk, etc. and check your kill switch with known good switch even if it’s not the right one. Or just omit it for now and see what happens. Maybe the switch is gunked up and causing intermittent on/off ??

 

[Dieselcamino]

Swapped a few plugs in and out, cleaned out the connections at the kill switch as well. I've just never seen on any motor where the plug will spark when near a ground but not at all when grounded

 

[BrettS]

Get a good new plug Bosche or ngk, etc. and check your kill switch with known good switch even if it’s not the right one. Or just omit it for now and see what happens. Maybe the switch is gunked up and causing intermittent on/off ??

The 024-026-260 don't have a switch like a Husky, more a lever type arrangement.

 

[JMCK]

The 024-026-260 don't have a switch like a Husky, more a lever type arrangement.

Duh ! I was just working on a echo and forgot the 026 is a lever. Brain fart!!

 

[JMCK]

Swapped a few plugs in and out, cleaned out the connections at the kill switch as well. I've just never seen on any motor where the plug will spark when near a ground but not at all when grounded

How about if you wound a wire around s/p threads and then attach to the jug , just for curiosity sake?

 

[Dieselcamino]

How about if you wound a wire around s/p threads and then attach to the jug , just for curiosity sake?

Actually tried that, it won't spark then. But when you dangle the plug near the jug it arcs to the jug and the plug fires.

 

[JMCK]

Actually tried that, it won't spark then. But when you dangle the plug near the jug it arcs to the jug and the plug fires.

Hmmmm. So it’s obviously Taking the path of least resistance. I’m

Actually tried that, it won't spark then. But when you dangle the plug near the jug it arcs to the jug and the plug fires.

Maybe try doing this in dark room and see then what it’s doing. Perhaps the coil lead is “ leaking “ or the boot and it’s arcing that way ?

 

[L34]

Seems like a bad plug to me.
As above taking least resistance

 

[Dieselcamino]

Seems like a bad plug to me.
As above taking least resistance

Tried multiple plugs, same results

 

[Dieselcamino]

Hmmmm. So it’s obviously Taking the path of least resistance. I’m

Maybe try doing this in dark room and see then what it’s doing. Perhaps the coil lead is “ leaking “ or the boot and it’s arcing that way ?

Good or Bad however you look at it is, I took the coil out for inspection and reinstalled it, now it is working fine. Haven't reassembled it yet but don't want the problem to reoccur

 

[kevin j]

I hate problems when the symptom just mysteriously goes away without an explanation. It’s not solved it’s just hiding in the weeds to come back and bite me later on

 

[Dieselcamino]

I hate problems when the symptom just mysteriously goes away without an explanation. It’s not solved it’s just hiding in the weeds to come back and bite me later on

Exactly, fixed isn't fixed until I know how I fixed it

 

[KASH]

It had to be bad plugs there is far more resistance for electricity to go to ground from the spark plug outer shell across a Say 1/4 inch air gap than to travel and jump the 20 thou gap of a good plug to go to ground.
Lightning and electricity take all possible paths to ground.
Kash

 

[Dieselcamino]

It had to be bad plugs there is far more resistance for electricity to go to ground from the spark plug outer shell across a Say 1/4 inch air gap than to travel and jump the 20 thou gap of a good plug to go to ground.
Lightning and electricity take all possible paths to ground.
Kash

Unless I have 3 bad plugs, 2 of which being brand new

 

[Oletrapper]

Good or Bad however you look at it is, I took the coil out for inspection and reinstalled it, now it is working fine. Haven't reassembled it yet but don't want the problem to reoccur

Bingo! "I took the coil out for inspection and reinstalled it, now it is working fine."
There was obviously a bad connection at the coil. Corrosion probably, not allowing a proper ground. Take the coil off, clean all mounting areas and wire connectors. Make sure there are no bare spots on any of the wires. Reinstall using a business card or feeler gauge (very difficult for me) between coil and the magnets on the flywheel. The gap must be measured between the coil and the magnets on the flywheel. You should be good to go. Let us know how it works out. OT

 

[JMCK]

Bingo! "I took the coil out for inspection and reinstalled it, now it is working fine."
There was obviously a bad connection at the coil. Corrosion probably, not allowing a proper ground. Take the coil off, clean all mounting areas and wire connectors. Make sure there are no bare spots on any of the wires. Reinstall using a business card or feeler gauge (very difficult for me) between coil and the magnets on the flywheel. The gap must be measured between the coil and the magnets on the flywheel. You should be good to go. Let us know how it works out. OT

I’ve been suspicious of that coil from the start.

 

[Dieselcamino]

I’ve been suspicious of that coil from the start.

New coil ordered, with everything else eliminated it's the only suspect left

 

[ihookem]

Lucky it was just coil and you figured it out. I hate problems with my tools. I have no time for patients when my tools stop working and I get very upset. Some guys just like that type of troubleshooting but not me. I got mad when my miter saw plug fell out last week. The 7 tin trailer wires came out last week too and they are not wired on the truck the way they should be so I had to guess a bunch . However I got the trailer wires figured out and it sure feels good to not have to take it in to a mechanic so I do much of it myself .

 

[mikerudder]

Pull the plug turn saw muffler down pull you heart out,, and let it sit overnite,, hanging by the handle.
Some saws get flooded,, they need to be dried out good. No choke full throttle first start.
Go from there if it dont fire.
At this point it cant hurt,,,

Just did this on an 034 that wouldn’t start for the life of me
Now it’s a runner. Sometimes it’s the simple things.