CUB CADET FUEL SOLENOID SPECS

[Denis_Veilleux]

Good day all,

I got myself a Cub Cadet AGS2160 with a 16hp motor model 303447. The previous owner did not quite know electricity and ended up frying the majority of the electric circuit.

I'm at ease with that; I found the electrical diagram to rewire it but my issue is with the fuel solenoid. While starting, the fuel solenoid get it's electricity from the starter and there is a diode on that circuit to prevent the starter from drawing electricity (from that circuit) once the engine is running.

The diagram is really clear but, I have no specs on that diaode or the fuel solenoid current requirement. I know it's 12VDC fed but that's not enough to get the proper diode size/spec. Can anyone help?

Thanks
Denis

 

[Williy]

You might want to check this out:

CUB CADET,DIODE ASSEMBLY,759-3689,959-3689,

willy

 

[Richard001]

Welcome to TBN.

Where do you live ?

Search locally for a diode, 50 to 100 volts and 1 amp.

Here is an example:

https://www.jameco.com/z/1N4934RLG-On-Semiconductor-Standard-Diode-100V-1A-Through-Hole-DO-41_2308527.html

Here is another source:

https://www.newark.com/onsemi/1n4002g/standard-diode-1a-100v-59-10/dp/42K2816?st=100v%201a

I don't know if there are any Radio Shack places left, but there maybe other similar stores in your area.

Richard

 

[Mike1955]

And also Richard, Amazon has exactly what he wants!

 

[Richard001]

And also Richard, Amazon has exactly what he wants!

Can you show the link ?

 

[tomplum]

A point or two to consider. The fuel solenoid should be switched on in crank and run. You never want power to the coils and would find a diode in the kill harness for the coils. Creative wiring previously done could have damaged the diode for the kill harness as well.

 

[Denis_Veilleux]

You might want to check this out:

CUB CADET,DIODE ASSEMBLY,759-3689,959-3689,

willy

Thanks Willy. How / Where did you find the part number?

 

[Denis_Veilleux]

Welcome to TBN.

Where do you live ?

Search locally for a diode, 50 to 100 volts and 1 amp.

Here is an example:

https://www.jameco.com/z/1N4934RLG-On-Semiconductor-Standard-Diode-100V-1A-Through-Hole-DO-41_2308527.html

Here is another source:

https://www.newark.com/onsemi/1n4002g/standard-diode-1a-100v-59-10/dp/42K2816?st=100v%201a

I don't know if there are any Radio Shack places left, but there maybe other similar stores in your area.

Richard

Thanks Richard, It's not a problem finding a place to get the Diode but, I'd like to know how did you come up with 50 to 100 volts and 1 amps?

 

[Denis_Veilleux]

A point or two to consider. The fuel solenoid should be switched on in crank and run. You never want power to the coils and would find a diode in the kill harness for the coils. Creative wiring previously done could have damaged the diode for the kill harness as well.

Thanks Tomplum, Regarding fuel solenoid, that is why I was asking for the Diode in the first place so I could get current to the solenoid while starting. As to the Diode in the kill harness, I looked the the diagram over again and there is no Diode. I don't know how power could get to the coils when all the kill harness does is ground (-) the coils to stop the motor...

 

[Richard001]

I'd like to know how did you come up with 50 to 100 volts and 1 amps?

The battery voltage is 12V normally. Could go to 15 with a good charging alternator. So a 100V reverse voltage rating will be more than adequate to prevent the voltage from bleeding back into the fuel shut off coil.

The 1 amp forward current rating should be more sufficient to power the fuel solenoid during the engine crank cycle.

I looked the the diagram over again and there is no Diode.

This line is confusing me. You ask for a recommend diode so that the fuel solenoid could be power while the engine is cranking. There clearly is a diode in the wiring diagram you posted.

Richard

Retired Electric system engineer.

 

[Williy]

Dennis_Veilleux I was a storekeeper in the Navy and know how
to get around in the system. I was the only one who could pull parts
from the supply rooms on board ship by cross referencing part numbers
etc. All the other storekeepers had to order from the states for weapons
systems parts.

willy

 

[Denis_Veilleux]

The battery voltage is 12V normally. Could go to 15 with a good charging alternator. So a 100V reverse voltage rating will be more than adequate to prevent the voltage from bleeding back into the fuel shut off coil.

The 1 amp forward current rating should be more sufficient to power the fuel solenoid during the engine crank cycle.



This line is confusing me. You ask for a recommend diode so that the fuel solenoid could be power while the engine is cranking. There clearly is a diode in the wiring diagram you posted.

Richard

Retired Electric system engineer.

Thanks Richard, very clear.

It's Tomplum that was talking about a diode on the Kill circuit and I replied to him that I did not see one on that specific circuit ''Kill circuit''

 

[Denis_Veilleux]

Dennis_Veilleux I was a storekeeper in the Navy and know how
to get around in the system. I was the only one who could pull parts
from the supply rooms on board ship by cross referencing part numbers
etc. All the other storekeepers had to order from the states for weapons
systems parts.

willy

Army myself for 34 years, we called you guys Supply Tech. And yes, some of you guys could pull out a rabbit from any places you could think of . Thanks again

 

[rScotty]

That small picture of the wiring doesn't tell me what the purpose of the diode is in that circuit. As shown, it apparently prevents a backflow of current to the starter from some other source voltage - but I can't imagne what that might be.
Based on what is shown, I would wire it differently. Simply wire the fuel solenoid to a key switched terminal on the ignition switch.
Be sure to place a fuse in the switched line to the fuel solenoid. You can also add the diode if you wish. I can't see what it does so cannot say why or not. But rating one correctly is easy:

To calculate the amp rating of the fuse or the diode use your VOM to measure the resistance of the solenoid coil. Then by ohm's law the amperage drawn by that amount of resistance is the system voltage (12 volts ) divided by the solenoid coil resistance. Check for any other circuit in series and add those amperage draws as well. Then select a fuse and diode with at least twice that total calculated amp draw to allow for heating and voltage spikes.

 

[Denis_Veilleux]

That small picture of the wiring doesn't tell me what the purpose of the diode is in that circuit. As shown, it apparently prevents a backflow of current to the starter from some other source voltage - but I can't imagne what that might be.
Based on what is shown, I would wire it differently. Simply wire the fuel solenoid to a key switched terminal on the ignition switch.
Be sure to place a fuse in the switched line to the fuel solenoid. You can also add the diode if you wish. I can't see what it does so cannot say why or not. But rating one correctly is easy:

To calculate the amp rating of the fuse or the diode use your VOM to measure the resistance of the solenoid coil. Then by ohm's law the amperage drawn by that amount of resistance is the system voltage (12 volts ) divided by the solenoid coil resistance. Check for any other circuit in series and add those amperage draws as well. Then select a fuse and diode with at least twice that total calculated amp draw to allow for heating and voltage spikes.

Thanks Scotty, Your explanation is very clear. As to the electric diagram, I'll attach it to my reply but you figured it out correctly: it was to prevent the backflow of the current to the starter once the motor is running. Could not hook up the solenoid to the key switch as the current is cut off from all other position while starting.

 

[Richard001]

Denis, can you give us an update on your progress ?

 

[Williy]

On the cub cadet that I had I added a small pump for fuel got rid of
the one on the carb put choke on full turn key to start instant start
saves wear and tear on started

amazon has them for around $10

willy

 

[tomplum]

Thanks Tomplum, Regarding fuel solenoid, that is why I was asking for the Diode in the first place so I could get current to the solenoid while starting. As to the Diode in the kill harness, I looked the the diagram over again and there is no Diode. I don't know how power could get to the coils when all the kill harness does is ground (-) the coils to stop the motor...

Twins w/o a controller use a diode in the kill wire between the two coils. You'll see a lump in the harness.