321d fuel/electrical problems

[banshee350]

I just had to replace my wiring harness in my 321d due to mice chewing the other harness. Now when I try to start the mower the only way I can get it to run is to hold the key switch in the start position. As soon as I release the switch the mower shuts off. I am pretty sure it is an electrical issue. It looks like the fuel solenoid opens when I turn the key but then closes when I let the key go (I have bled the fuel system). I have looked at the schematic and can't seem to figure out what I have hooked up wrong. If anyone has any suggestions I sure would like to hear them.

Thanks

 

[KennyV]

There are two common type DIESEL fuel solenoids...
One pulls and then holds the fuel on...
The other type pulls to shut the fuel off.

Since you are saying it holds the solenoid during starter engagement... then when started you release the key to run and the solenoid releases ... I suspect you have the first type... The pull and hold type.
You can verify that by checking At the solenoid... If it has 3 wires one is Common, One is Pull and the other is Hold.

if you have a copy of the schematic, look at where those wires On the solenoid should connect... :smile:KennyV

 

[banshee350]

Kenny
I see what you are saying. According to the schematic the white wire is the hold wire. I got so frustrated I put the old harness back on and it is doing the same thing now (worked fine before). Do you know what inputs would cause the solenoid to close (lo oil press hi water temp Etc) and how I could test those switches. Do you think the fuel solenoid failed? I really want to figure this out without taking it to a shop (I bet that will be expensive)

 

[KennyV]

Check what you have available on the white connection... BOTH at the solenoid & the tractor wiring harness that feeds the white wire.
Depending on how the system is configured... the tractor could either apply 12 volts or Ground to the white wire...
If the common on the solenoid is wired to Ground, then the Pull & the Hold will need 12 volts to work.

If the common on the solenoid is wired to 12 volts Then the Pull & the Hold will need a Ground source to work. (I have one set up like this using Murphy gauges to watch oil pressure and engine heat)....

I suspect yours is the first type that is looking for a 12 volt hold source... that should be available from the key switch whenever the key is in the run position...

With the key switch in the Run position,check if you have voltage on the tractor side that connects to the white wire . If not check for a fuse problem.. :smile:KennyV

 

[173abn]

I'm looking at my wiring diagram and the white wire goes to a module-switch interlock as well as the green.could be it went bad.also as Kenny said I'd check the fuses if you have'nt already.could be a bad solenoid.Might not hurt to replace it.Curious as to how much that wiring harness set you back? Mice are a bummer, I 'm at constant war w/them in my barn.Let use know what you find..russ

 

[banshee350]

I think I have figured out the problem. The new harness plug for the interlock module has the green and white wires reversed. I looked the harnesses over prior to installing but I didn't notice these wires were reversed. So it appears I burned up the interlock switch when I tried to start the mower (12 volts to ground). I noticed this after reinstalling the old harness. I emailed grasshopper service and they gave me some helpful troubleshooting guidelines. I ended up hooking a fused wire from the red/white wire on the ignition switch straight to the hold wire on the fuel solenoid and the mower started up and ran fine. When I turn the ignition off it closes the solenoid. I am going to order a new interlock switch (which is alot cheaper than a solenoid) and I guess I will have to cut my brand new harness and splice the wires in correctly. I paid $125 for the harness (brand new) from george o hays(maybe it was defective and that is why it was so cheap). Have you figured anything that will keep mice out of your wiring? I am thinking of trying moth balls. Once I get the module I will let you know if it worked. Thanks for all the help

 

[KennyV]

Have you figured anything that will keep mice out of your wiring?

Cats..... :smile:KennyV

 

[banshee350]

My cats prefer to eat baby pigeons, they think the mice are their "buddies".

 

[reynoldston]

My cats prefer to eat baby pigeons, they think the mice are their "buddies".

Sure sound like my cat, a mouse is something to play with.

 

[173abn]

Glad you figured out the problem,sorry you bummed some things up though.I always keep half a dozen traps going and bought this covered bait station at TSC.I put every thing where my dogs can't get to them.I had 4 piegons trying to nest in my loft a week ago so I went up at night w/a small flashlight taped to my bb rifle and got rid of that problem.Piegons are very messey and they tell their friends so I had no other choice.....russ