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Jlg 40H carb setup?

rbcanaday

Well-Known Member
Joined
Mar 11, 2015
Messages
72
Location
Walterboro, SC
That's called an "anti dieseling solenoid" and yes it shuts of flow of fuel through the carb, JLG uses it to shut the engine down. That way, when you shut the engine off, runs till it dies, that clears the gasoline from the intake system, now when you switch over to propane there's no mixture interference from gasoline. Make sure that pin inside the solenoid will move in and out easily with your fingers, ethanol gas will cause those solenoids to get stuck. If it moves freely, put a jumper wire from a battery on the wire and ground the solenoid body, see if it clicks and works the pin. If it works, you likely aren't getting a signal on the wire going to the solenoid.

fixed one issue but still think solenoid is bad. It wasn’t getting power because somebody flipped the switch to lp.
Got that fixed but it doesn’t want to shut down without killing master switch. So I think the solenoid maybe isn’t closing off right. The bad fuel had corroded it pretty bad. We got it free and even tested it but something must be bad with it since it won’t shut off. Thoughts?
 

rbcanaday

Well-Known Member
Joined
Mar 11, 2015
Messages
72
Location
Walterboro, SC
I have one of those carbs, new in the box with a Genie part number number on it. Same engine. Customer changed his mind after I bought it, I got stuck with it. I'd let it go pretty cheap. Let me know if you're interested.

ive got this one going but something still seems not quite right. I’d be interested but depends on price. Email me and let me know price.
rbcanaday@gmail.com
 

OFF

Senior Member
Joined
Sep 30, 2009
Messages
1,048
Location
Alberta, Canada
Occupation
HD Mechanic
fixed one issue but still think solenoid is bad. It wasn’t getting power because somebody flipped the switch to lp.
Got that fixed but it doesn’t want to shut down without killing master switch. So I think the solenoid maybe isn’t closing off right. The bad fuel had corroded it pretty bad. We got it free and even tested it but something must be bad with it since it won’t shut off. Thoughts?

Normally when I see this "not shutting off" thing happening, it involves the alternator.
The alternator needs to have ignition power applied to it to begin charging (excite it), but once charging begins, that excite wire become powered by the alternator. There is always a diode (one-way valve) in the circuit to prevent this back-flow from keeping the engine running after you shut the engine off.
Often happens when someone has changed the alternator to a different style or brand, or maybe just messed with the wiring. Diodes don't normally fail, but it can happen when subjected to high current.
The game will be to find the diode or add another diode to the smaller power wire at the alternator.
 

rbcanaday

Well-Known Member
Joined
Mar 11, 2015
Messages
72
Location
Walterboro, SC
Normally when I see this "not shutting off" thing happening, it involves the alternator.
The alternator needs to have ignition power applied to it to begin charging (excite it), but once charging begins, that excite wire become powered by the alternator. There is always a diode (one-way valve) in the circuit to prevent this back-flow from keeping the engine running after you shut the engine off.
Often happens when someone has changed the alternator to a different style or brand, or maybe just messed with the wiring. Diodes don't normally fail, but it can happen when subjected to high current.
The game will be to find the diode or add another diode to the smaller power wire at the alternator.

thanks. Let me know how much for carb
 

rbcanaday

Well-Known Member
Joined
Mar 11, 2015
Messages
72
Location
Walterboro, SC
Just an update. Got machine running ok after going through carb 3 times. still doesn’t idle as good as I think it should. Almost shuts down when I swap from ground to platform. Throttles down too low it seems. It didn’t want to shut down without dieseling, so I replaced the fuel shutoff solenoid at 150$. Still wants to diesel when shut down unless master switch is shut off.

It’s running but still got some work to do. Would like to try lp but that side of machine hasn’t been used in a very long time and I don’t have a tank.
 
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