Electric Fuel Pump Wiring

[Bill D 2,042]

Hi,

 

I am thinking of adding an electric fuel pump to one of my tractors with a Kohler M12.  I would like to wire it to shut off if one of the safety switches shuts off the machine.  How do I do this on a Magneto equipped tractor?  If it had a powered ignition, like my Onan equipped machine it would be easy.  Thanks for the help.  Bill

[johnnymag3 2,554]

Bill, why not just install it inline with one of the safety switches that use 12 volts...if the switch opens....power is interrupted....pump shuts off ???

 

my .02 cents and now I have .23 cents left from my .25 cents I made off you .

[gwest_ca-(File Mod) 11,161]

What is the model number of your tractor?

 

Garry

[peter lena 8,950]

BILL D , this what i did for mine , also used th  CARBOLE MICRO ELECTRIC FUEL PUMP , 2 - 3.5 PSI RATING , VERY QUIET ON THE UNI STRUT MOUNT ,  pete

 

[953 nut 56,458]

I like the way you think.           safety is very important. You can pick up a five pin relay and socket at any auto parts store for very little money. Here is how it will work;    With the key in the on position power will go to the relay coil  but it would not close because the blue wire to your magneto is not grounded. Power will also go to the fuel pump through the 87a/30 contacts. if  the PTO is off Or it is on and a driver is in the seat the 87a/30 contacts will continue to supply power to the fuel pump as long as the key is on.. If the driver leaves the seat while the engine is running and the PTO is on then the seat switches will ground out the blue wire to the magnito which will also activate the relay making up the 30/87 contacts and power to the fuel pump will be interrupted.

Do Not do as I had suggested, it could fry the magneto!

 

Edited September 29, 2020 by 953 nut
bad idea

[Bill D 2,042]

Have you done this on your tractor?  The way I read the schematic, the coil of the relay will allow 12V+ to pass to the kill wire for the magneto and fry it. 

 

I like the concept, and I thought of something like this.  I afraid it would fry my magneto.   I would be doing this on a 1982 GT 1142, and a 1988 312-8 Thanks.  Bill

Edited September 29, 2020 by Bill D

[953 nut 56,458]

7 hours ago, Bill D said:

Have you done this on your tractor?  The way I read the schematic, the coil of the relay will allow 12V+ to pass to the kill wire for the magneto and fry it. 

 

I like the concept, and I thought of something like this.  I afraid it would fry my magneto.   I would be doing this on a 1982 GT 1142, and a 1988 312-8 Thanks.  Bill

Bill, you are correct.      I woke up in the middle of the night questioning if there would be a problem with this. It probably could be done if the ignition switch were changed over to a Battery type switch and a Kill Relay added, that would allow the safety switches to be powered with 12 Volts rather than being grounded.

Here are a couple of threads that cover most of the information needed.

My morning is rather full, but I will work on this tonight.

 

[Bill D 2,042]

No rush, and no apology necessary.  I'm not in a hurry to convert my tractors.  The mechanical and vacuum pumps I have are currently working.  This is just for future use.  Bill

[rick 237]

I installed electronic pumps in two of my WH's to get rid of long crank time with the under seat gas tank.  I took power from the accessory circuit and protected the pump with a 5 Amp fuse.  No safety lectures, please, I wanted the pump to prime the carb after setting for weeks at a time.  The seat switches failed and are bypassed, the pto switches on the grass cutter machine are toast and bypassed. NO ONE uses the tractors but me, no kids in the house.

[johnnymag3 2,554]

Hide the keys...!!!!!!      For future reference....

[953 nut 56,458]

8 hours ago, Bill D said:

no apology necessary.

The most important thing to me is that any information I share is accurate and safe because these posts live on and are used as a reference years later. If others put out inaccurate or irrelevant information we try to correct them if we can.

 

I think we have a winner!

The '92 to '97 300 series use a seat switch relay which would require the leads on the seat switch to be changed from NC to NO and the ignition switch to be changed to a Battery switch 103-990 and some minor rewiring. No kill relay, PTO switch remains the same, and no way that 12 volts will get to the magneto. Just connect the fuel pump to the wire between the seat switch and the relay.

 

[Bill D 2,042]

Any idea how I could do this on my 1982 GT 1142 with out a major rewire?  I was hoping to avoid major wiring changes.  If not I may just stick to electric pumps on the tractors with powered ignitions.  I have had pretty good luck using pulse pumps to replace the mechanical pumps on my Kohlers.  Bill

[gwest_ca-(File Mod) 11,161]

1982 and 1983 should have the same wiring.

Garry

 

[gwest_ca-(File Mod) 11,161]

For the GT-1142 I would add a second seat switch that is normally open. NO The one there now is normally closed. NC

Power the fuel pump with the Accessory terminal of the ignition switch. It only delivers power in the Run switch mode. Wire to the new second NO seat switch and then to the pump.

 

Sit in the seat to start the tractor and turn the key to Run for a few seconds to build up fuel pressure. Then advance the key to the Start position. This may not be required depending on how long the tractor has sat idle.

 

Operator falls off the seat - original seat switch closes and kills the ignition - second seat switch opens and kills the fuel pump.

 

Garry

 

[gwest_ca-(File Mod) 11,161]

1988 312 wiring

Garry