John deere snow blower?

[Thunderman]

I own a john deere walk behind snow blower thats about 7 yrs old. When I am removing snow while it is snowing I can get about half of my driveway done and it quits, something electrical is getting wet and it won't start untill it dryes is there something I can do to stop this any info would be appreciated thanks

Thunderman

[The_Duckslayer]

Best I can think of it to check all the wires for a fray. Could be that it is not touching any metal but when it gets wet it is making contact through a drip of water somewhere. Fortunately there are not that many wires on a snow thrower. Hope that helps. Take care and N Joy the Hunt././Jimbo

[BIG DS]

Have you checked for spark after it quits? If the plug wire gets wet, just put some di-electric grease in the plug boot and that will solve that problem. If the boot is still dry and there is no spark, it will more than likely be a problem up under the flywheel. Also make sure that the carb is not freezing up. Make sure and warm the blower up before putting it to work. That will get the carb clean and help keep it from freezing. There is also a hole on the carb that serves as float bowl vent that gets plugged and contributes to the freeze up problem.

[harleyharry]

There is no wiring on your engine that can get wet and short out, causing the engine to quit. The only way to shut down the engine electricaly is by shorting the ignitioon to ground.

When the engine quits, test the engine for spark at the spark plug. If you have spark just after the engine quits, you do not have an electrical problem. If there is no spark, look under the air box shroud which covers the carb. You will see two or three wires that attach to a small screw next to the throttle control. Remove the wire that goes up into the shroud area. Retest for spark. If no spark, you need an ignition coil. If you have spark, check the safety switches at the handles for loose wiring.

If all of your tests show good spark at all times, I suspect that you have one of the engine valves sticking when the engine heats up. Not very common on a snowblower engine, but can happen.

Also, check the fuel cap and make sure the small disc is not pushed all the way to the top of the cap. This will shut off the fuel tank vent, and cause the engine to starve for fuel .

Hope this is helpful.

Harry

[Macgyver55]

Quote:

There is no wiring on your engine that can get wet and short out

Sure there is! Any wiring that is necessary to run or shut off the engine can get wet, ground out and kill the engine. This would include the plug wire, any wires that go to a key or on/off switch, or safety switch and/or wires the go to the throttle stop on the engine that kills the motor when you close the throttle. If any of these get wet and ground out it can kill the engine.

A couple trouble spots to look at are where the plug wire comes out of the recoil housing (or shroud) and if it uses a key switch it could have moisture in it. Another thing you can try is running it and using a small spray bottle to mist different areas to see if you can make it die to narrow it down to where the problem is.

[harleyharry]

I have been repairing these engines since 1970, and other than the old engine with points and condensers in them, have never seen or heard of a water related problem on a mag style ignition system. Battery ignition, yes, magneto ignition, no.

If there is a spot in the wiring that is bare enough to allow water to cause a problem, that problem will arise weather there is moisture or not.

Thunderman can run his engine for quite a while before the engine quits. If his ignition is shorting out, it will do it long before he says the engine quits.

Thunderman, please let us know what you find wrong. It may help others with the same problem in the future.

Harry

[Thunderman]

Thanks Guys for your input I will trouble shoot when it happens again.That is one thing about the FM site we are a big family here and I enjoy all the topics weather we need somthing fixed or ect.Happy Holidays to all and thanks again.

Todd

[Macgyver55]

Quote:

I have been repairing these engines since 1970, and other than the old engine with points and condensers in them, have never seen or heard of a water related problem on a mag style ignition system.

Me too....started my first job as a mechanic in 1972....still doing it today (at a different place for the last 32 years). I wasn't refering to the actual "ignition" system as much as the engine shut down wiring. They normally use some type of ground to shut off the motor. If any of the wiring for that part of the system gets wet or rubs through it to ground it can most certainly shut off. It really doesn't matter which style (battery or mag) they use, if the coil wire shorts on the shroud from moisture or rub through it can/will die also.

Thunderman, does it die like you shut it off or kind of sputter and die slowly when it does it. Can you sense it coming with any erratic symptoms before it dies?

And, are you sure its a moisture related problem or could it simply be heat? Coils that are bad can sometimes quit working when they get hot and work again when cooled off. If it turns out to still have spark after it dies, don't overlook the gas cap vent. It could be plugged causing a vacuum in the tank and not letting it flow enough fuel.

[harleyharry]

Thanks for the clarification Macgyver. I took from your original post, that you felt that moisture alone would cause the igniton to fail, like the old style ignition on autos.

By the way, good to hear there are some of us old timers out there still gettingit done. I am semi retired, which means I do not work weekends anymore.

Harry

[Thunderman]

Quote:

I have been repairing these engines since 1970, and other than the old engine with points and condensers in them, have never seen or heard of a water related problem on a mag style ignition system.

Me too....started my first job as a mechanic in 1972....still doing it today (at a different place for the last 32 years). I wasn't refering to the actual "ignition" system as much as the engine shut down wiring. They normally use some type of ground to shut off the motor. If any of the wiring for that part of the system gets wet or rubs through it to ground it can most certainly shut off. It really doesn't matter which style (battery or mag) they use, if the coil wire shorts on the shroud from moisture or rub through it can/will die also.

Thunderman, does it die like you shut it off or kind off sputter and die slowly when it does it. Can you sense it coming with any erratic symptoms before it dies?

And, are you sure its a moisture related problem or could it simply be heat? Coils that are bad can sometimes quit working when they get hot and work again when cooled off. If it turns to still have spark after it dies, don't overlook the gas cap vent. It could be plugged causing a vacuum in the tank and not letting it flow enough fuel.It just dies like I just shut it off the only time it does it is when alot of snow is getting on top of the motar otherwise it works OK. Thunderman