I have an older Husqvarna 50 that has been running great. I was cutting last week and found that it wouldn't turn off. Had to choke it to get it to stop running. Figured it was a bad switch so I ordered a factory switch. Installed the switch today. Still have the same problem. Thinking I may have a short somewhere, but not sure where it could be. this is what I have tried so far... Installed new switch and verified it is working correctly. Checked wire from coil to switch for continuity. It's fine. Even took it off and did a shake test with multi meter attached. Checked out good. Cleaned wire connector ends. The weird thing is that the switch verifies working correctly with the multi meter, but when I hook up the wire coming from the coil to the switch, the switch does not work right. The saw still starts and runs fine, just wont shut off with the switch. Where do I go from here? I just hate taking it into the shop when It has to be something simple. Thanks in advance.
Where does the other switch terminal go? Should go to a ground screw. Make sure that screw isn't corroded .
It does go to a ground screw, which is new with a new hole too. Checked continuity on the new switch and it is working correctly. But when I connect the wire from the coil to the switch, they switch will not ground. I have been thinking about it. There must be a ground that isn't making contact somewhere and it's not letting the switch ground it. Going to pull the coil off tomorrow and make sure all connections are clean. I did notice lat time cutting that when I cut using the top of the bar, the saw died a couple of times. That could be an indication there is a wiring problem somewhere I guess.
I had a Stihl that had a mangled plastic switch. The contacts couldn't quite touch, barely scrub. So I killed it with choke until I could remedy. Clean contacts and inspect visually. Keep at it, sounds like you know what to look for, just keep looking.
I had a coil module that the only thing left to be wrong was the internal kill circuit had failed. Try a new AM coil for ~$10. I've used 5 of them for for 51, 55 and they all work.
Probably a dumb question...but the new hole that this ground screw is in...is it metal...as in an actual grounded point? I'd grab a jumper wire and hook up to the shut-off wire...if you take that to ground it should shut off...if not then the wire into the coil must be broke...or inside the coil itself.
take the wire off from the switch, with the saw running touch the metal terminal to a part of the unpainted case. this will prove that the coil and wire are fine. I suspect the screw holding the switch in or that there is something on the teminal. with the saw off. and the switch in the off position place one multimeter lead on teh saw jug and the other end where the kill wire goes into the coil. what is teh reading in ohms?
That is the problem. With the wire connected to the switch, it doesn't matter if the switch is on or off position, there is resistance there. With the wire off the switch, the switch works as normal.
I bought an AM coil, once. It failed in a few short months. Guess it was a good $10 answer to a question. Only oem from then on.
It's more model-specific than that though. Why the 394 coil is junk, I have no idea. Chinese ms361 coils are the same way. Junk out of the box. But the Chinese 066, 044, and 350 coils seem perfect. Lol.
By the way, I didn't listen to your advice. I bought that same POS 394 aftermarket coil and threw it in the circular file after it wouldn't run. Such a crap shoot, but for ten bucks I thought it was worth it. Not
Good to know. Even when the shy-knee one ran, seemed it must've had different timing curve. The saw was on the flat side. When I went back to OE it was like I was spraying NOS. Throttle response was night and day.
Update: Pulled coil and cleaned all conections. Reinstalled coil and checked switch continuity again. Still worked fine except when wire from coil to switch was hooked up. Put it back together as I needed to leave the house. Fired it up to make sure it ran after pulling coil. Ran fine. Flipped switch off and the saw shut off. Tried it a few more times and it seems to be working fine. Now not fully sure what fixed it. Weird...
Probably a little corrosion somewhere on a ground connection. Or the switch wire has a break in it and it's making contact now. If it does it again you know where to look
