Repairing glow plug/starter switch wiring farmall 504

[down_right]

So I have replaced most of the electrical system including starter/solenoid, upgraded to a 1 wire “fast start” alternator (63 amps), added voltmeter, new glow plug meter, and replaced the old key—>starter button to a convenient turn-key ignition switch. The tractor starts, but then (as I stop turning the key over), it dies. The issue was the same when I had the original setup with the original key/starter button combo, and along with old wiring and bad readings on the plugs, I am working on that next.

I plan to replace all 4 plugs, and install a switch relay powered by the key switch. If I’m right the 4 plugs take about 8 amps each, so 32amps from the alternator’s capacity of 63, so the relay I get shouldn’t need to be more than 35-40 right? I’m not sure of whether they make 35amp relays, or just in steps of 10amps 40), or whether I should just get a 40 amp relay in the first place though. Also should I place the inline 40A fuse before the relay, or after it on the high amp output?

From what I have seen how I would install the electrical lines so that the power to the glow plug setup is only receiving power when the key is on are as follows:

1) ignition key switch (accessory/ignition terminal) feeds the low amp input side of the glow plug relay
2) other end of the low amp side of the relay attaches to ground somewhere on tractor’s chassis
3) high amp input to the relay comes from the same terminal post on the starter that the battery cable/lead from alternator is attached to
4) high amp output then goes to the glow plug switch
5) other terminal on the glow plug switch goes to one side on the glow plug meter
6) other side on the glow plug meter then finally leads to the little “terminal” where the first glow plug is connected to which then provides power to heat the plugs (in series)

Does this sound correct?

Last thing I am unsure about it how it appears that from the output on the glow plug meter are two 12AWG wires ran in parallel (crimped under one o ring terminal) that then runs to the block near the first glow plug, where the same 2 wires (once again crimped under the same 1 connector). Is there any reason for this? Or could I simply have a single 8 or 10 awg wire leading from the meter to the plugs?

 

[wore out]

So I have replaced most of the electrical system including starter/solenoid, upgraded to a 1 wire “fast start” alternator (63 amps), added voltmeter, new glow plug meter, and replaced the old key—>starter button to a convenient turn-key ignition switch. The tractor starts, but then (as I stop turning the key over), it dies. The issue was the same when I had the original setup with the original key/starter button combo, and along with old wiring and bad readings on the plugs, I am working on that next.

I plan to replace all 4 plugs, and install a switch relay powered by the key switch. If I’m right the 4 plugs take about 8 amps each, so 32amps from the alternator’s capacity of 63, so the relay I get shouldn’t need to be more than 35-40 right? I’m not sure of whether they make 35amp relays, or just in steps of 10amps 40), or whether I should just get a 40 amp relay in the first place though. Also should I place the inline 40A fuse before the relay, or after it on the high amp output?

From what I have seen how I would install the electrical lines so that the power to the glow plug setup is only receiving power when the key is on are as follows:

1) ignition key switch (accessory/ignition terminal) feeds the low amp input side of the glow plug relay
2) other end of the low amp side of the relay attaches to ground somewhere on tractor’s chassis
3) high amp input to the relay comes from the same terminal post on the starter that the battery cable/lead from alternator is attached to
4) high amp output then goes to the glow plug switch
5) other terminal on the glow plug switch goes to one side on the glow plug meter
6) other side on the glow plug meter then finally leads to the little “terminal” where the first glow plug is connected to which then provides power to heat the plugs (in series)

Does this sound correct?

Last thing I am unsure about it how it appears that from the output on the glow plug meter are two 12AWG wires ran in parallel (crimped under one o ring terminal) that then runs to the block near the first glow plug, where the same 2 wires (once again crimped under the same 1 connector). Is there any reason for this? Or could I simply have a single 8 or 10 awg wire leading from the meter to the plugs?

Since the tractor "dies" when you release the starter switch/button you must somehow have the fuel shutoff solenoid on the injection pump connected to the "START" circuit?

(1.) Your plan to activate the glow plug relay from the "Accessory" terminal on the key switch won't work because the "ACC" terminal is "hot" in run, as well as in the "ACC", and you don't want the glow plugs to be activated at all times that the "ignition switch" is "ON".

(6.) The G.P.'s are connected in PARALLEL.

 

[used red MN]

So I have replaced most of the electrical system including starter/solenoid, upgraded to a 1 wire “fast start” alternator (63 amps), added voltmeter, new glow plug meter, and replaced the old key—>starter button to a convenient turn-key ignition switch. The tractor starts, but then (as I stop turning the key over), it dies. The issue was the same when I had the original setup with the original key/starter button combo, and along with old wiring and bad readings on the plugs, I am working on that next.

I plan to replace all 4 plugs, and install a switch relay powered by the key switch. If I’m right the 4 plugs take about 8 amps each, so 32amps from the alternator’s capacity of 63, so the relay I get shouldn’t need to be more than 35-40 right? I’m not sure of whether they make 35amp relays, or just in steps of 10amps 40), or whether I should just get a 40 amp relay in the first place though. Also should I place the inline 40A fuse before the relay, or after it on the high amp output?

From what I have seen how I would install the electrical lines so that the power to the glow plug setup is only receiving power when the key is on are as follows:

1) ignition key switch (accessory/ignition terminal) feeds the low amp input side of the glow plug relay
2) other end of the low amp side of the relay attaches to ground somewhere on tractor’s chassis
3) high amp input to the relay comes from the same terminal post on the starter that the battery cable/lead from alternator is attached to
4) high amp output then goes to the glow plug switch
5) other terminal on the glow plug switch goes to one side on the glow plug meter
6) other side on the glow plug meter then finally leads to the little “terminal” where the first glow plug is connected to which then provides power to heat the plugs (in series)

Does this sound correct?

Last thing I am unsure about it how it appears that from the output on the glow plug meter are two 12AWG wires ran in parallel (crimped under one o ring terminal) that then runs to the block near the first glow plug, where the same 2 wires (once again crimped under the same 1 connector). Is there any reason for this? Or could I simply have a single 8 or 10 awg wire leading from the meter to the plugs?

I am attaching a wiring diagram for your tractor, make sure you are looking at the right diagram for the diesel.
Wiring diagram
You must not have a stock injection pump since you must have an electric solenoid on the pump. In that era IH just used the throttle that popped over the idle detent to kill the fuel. If you don’t have a solenoid on the pump you better call that tractor Christine!
I believe the reason there are two glow plug wires is because they run through a plug in connector, must have been an assembly line thing. It was probably to many amps to go through one spade terminal reliably l, so they used two. You can run your glow plugs off the accessory terminal but you need a push button in there for momentary on operation.

 

[rustred]

So I have replaced most of the electrical system including starter/solenoid, upgraded to a 1 wire “fast start” alternator (63 amps), added voltmeter, new glow plug meter, and replaced the old key—>starter button to a convenient turn-key ignition switch. The tractor starts, but then (as I stop turning the key over), it dies. The issue was the same when I had the original setup with the original key/starter button combo, and along with old wiring and bad readings on the plugs, I am working on that next.

I plan to replace all 4 plugs, and install a switch relay powered by the key switch. If I’m right the 4 plugs take about 8 amps each, so 32amps from the alternator’s capacity of 63, so the relay I get shouldn’t need to be more than 35-40 right? I’m not sure of whether they make 35amp relays, or just in steps of 10amps 40), or whether I should just get a 40 amp relay in the first place though. Also should I place the inline 40A fuse before the relay, or after it on the high amp output?

From what I have seen how I would install the electrical lines so that the power to the glow plug setup is only receiving power when the key is on are as follows:

1) ignition key switch (accessory/ignition terminal) feeds the low amp input side of the glow plug relay
2) other end of the low amp side of the relay attaches to ground somewhere on tractor’s chassis
3) high amp input to the relay comes from the same terminal post on the starter that the battery cable/lead from alternator is attached to
4) high amp output then goes to the glow plug switch
5) other terminal on the glow plug switch goes to one side on the glow plug meter
6) other side on the glow plug meter then finally leads to the little “terminal” where the first glow plug is connected to which then provides power to heat the plugs (in series)

Does this sound correct?

Last thing I am unsure about it how it appears that from the output on the glow plug meter are two 12AWG wires ran in parallel (crimped under one o ring terminal) that then runs to the block near the first glow plug, where the same 2 wires (once again crimped under the same 1 connector). Is there any reason for this? Or could I simply have a single 8 or 10 awg wire leading from the meter to the plugs?

why not just use a good push button switch to handle the amps and meter like the earlier models used. then run the 8 gauge wire up to the glow plugs . then use 12 gauge wires to hook them up in parallel. simple and easy. no turning switches on or off . done.

 

[Dieseltech]

Since the tractor "dies" when you release the starter switch/button you must somehow have the fuel shutoff solenoid on the injection pump connected to the "START" circuit?

(1.) Your plan to activate the glow plug relay from the "Accessory" terminal on the key switch won't work because the "ACC" terminal is "hot" in run, as well as in the "ACC", and you don't want the glow plugs to be activated at all times that the "ignition switch" is "ON".

(6.) The G.P.'s are connected in PARALLEL.

That tractor does not have an electric fuel shut off in the top cover unless someone added it. My 504D has manual cable pull shut off.

 

[down_right]

That tractor does not have an electric fuel shut off in the top cover unless someone added it. My 504D has manual cable pull shut off.

yeah i have to use the pull cable to turn the fuel off

 

[down_right]

why not just use a good push button switch to handle the amps and meter like the earlier models used. then run the 8 gauge wire up to the glow plugs . then use 12 gauge wires to hook them up in parallel. simple and easy. no turning switches on or off . done.

what amperage does the posh button switch need to be rated for? i guess i'm confused as it looks like the oem switch is only 10A, but the plugs need 32A?

 

[down_right]

Since the tractor "dies" when you release the starter switch/button you must somehow have the fuel shutoff solenoid on the injection pump connected to the "START" circuit?

(1.) Your plan to activate the glow plug relay from the "Accessory" terminal on the key switch won't work because the "ACC" terminal is "hot" in run, as well as in the "ACC", and you don't want the glow plugs to be activated at all times that the "ignition switch" is "ON".

(6.) The G.P.'s are connected in PARALLEL.

you sure about that? the point of the relay is so that the low amp circuit thats connected to the key can only be powered when the key is "on", and when they key is on, and the button is pushed, THEN the high amp circuit is completed to the glow plugs, but only for as long as the button is pushed.

i am referencing this video right here. it's for a farmall 656, but the concept should be the same

 

[used red MN]

I should have looked at the parts diagram closer and found the shut off cable. There is a rectangular timing window on the side of the pump held on by two screws about 5/8” wide x 1 1/4” long. Have someone start the tractor and then you immediately loosen the screws on the plate to leak off a little fuel to lower the pressure in the pump housing. If it stays running your injection pump needs rebuilt. If my suggestion above works the problem is the governor weight cushion ring in the pump has deteriorated and is breaking to pieces. This is plugging the return outlet check valve. When the pressure in the housing gets to high the pump plungers can’t return to refill the pumping cavities. No pumping, no running.
This shows a flex ring replacement in progress.
Flex ring replacement
Once wired correctly there is no reason why a relay won’t work in your glow plug circuit.

 

[rustred]

I should have looked at the parts diagram closer and found the shut off cable. There is a rectangular timing window on the side of the pump held on by two screws about 5/8” wide x 1 1/4” long. Have someone start the tractor and then you immediately loosen the screws on the plate to leak off a little fuel to lower the pressure in the pump housing. If it stays running your injection pump needs rebuilt. If my suggestion above works the problem is the governor weight cushion ring in the pump has deteriorated and is breaking to pieces. This is plugging the return outlet check valve. When the pressure in the housing gets to high the pump plungers can’t return to refill the pumping cavities. No pumping, no running.

check your return line,... loosen it at the pump , if it then runs the return is plugged with that stuff, is what i do.

 

[used red MN]

check your return line,... loosen it at the pump , if it then runs the return is plugged with that stuff, is what i do.

Easier to just loosen the timing window. If you go rustreds way you have to remove the actual check valve out of the aluminum pump housing.

 

[rustred]

Easier to just loosen the timing window. If you go rustreds way you have to remove the actual check valve out of the aluminum pump housing.

the check valve is in the tank.

 

[rustred]

the check valve is in the tank.

then u can blow out the line and check valve and run the tractor for a while till it plugs again. makes more sense to me.

 

[used red MN]

Just trying to make easy. Also trying to steer him away from finding out that unplugging the line will fix it and make it run. Then he keeps running it until it is banging metal to metal in there running metal filings all through his pump. There is also always the possibility that a chunk will float into the wrong spot an get it stuck at full fuel. Probably easy to kill off that 4 banger with the clutch. Takes a bit more when 6 lungs are fighting against you.

 

[wore out]

you sure about that? the point of the relay is so that the low amp circuit thats connected to the key can only be powered when the key is "on", and when they key is on, and the button is pushed, THEN the high amp circuit is completed to the glow plugs, but only for as long as the button is pushed.

i am referencing this video right here. it's for a farmall 656, but the concept should be the same

You did not mention a "push button" in your initial post, just grounding one side of the relays coil and powering the other side fron the "ignition switch".

 

[used red MN]

then u can blow out the line and check valve and run the tractor for a while till it plugs again. makes more sense to me.

Okay, I’ll take your word on it. Most of my experience with these pumps comes from GM diesels, they all had check valves in the pumps. I did a few on Deere tractors and I want to say they also had check valves. I know I have heard folks on here talking about tractor pumps and knocking the check balls out so they can run their pump in “shake and bake” mode. No harm in him taking the line off and running it. If it pumps fuel out and runs then you win the prize. If it don’t then the fitting is plugged or it is a check valve and it is plugged. Or maybe he has some other problem.
//!! BTW down_right just staying the obvious if you don’t know. The supply line feeds the pump from the filters. The return line is the one that comes back out on the top.

 

[down_right]

I should have looked at the parts diagram closer and found the shut off cable. There is a rectangular timing window on the side of the pump held on by two screws about 5/8” wide x 1 1/4” long. Have someone start the tractor and then you immediately loosen the screws on the plate to leak off a little fuel to lower the pressure in the pump housing. If it stays running your injection pump needs rebuilt. If my suggestion above works the problem is the governor weight cushion ring in the pump has deteriorated and is breaking to pieces. This is plugging the return outlet check valve. When the pressure in the housing gets to high the pump plungers can’t return to refill the pumping cavities. No pumping, no running.
This shows a flex ring replacement in progress.
Flex ring replacement
Once wired correctly there is no reason why a relay won’t work in your glow plug circuit.

my dad just had it rebuilt last year. for the second time actually, in the past few years. are these injector pumps/tractors known to be garbage, or easily damaged somehow?

also, it seems what you're describing is just or similar to bleeding the system of air? I've replaced the fuel filter cartridge, and bled the system and fuel leaks out of the pump/lines just fine.

maybe i should be more specific, the tractor doesn't fully turn on. it gets to the point where it seems like it's just on the edge of fully turning over (to when you would then stop pressing the starter button), but then it just sortof weakens, more and more until you stop pressing the ignition button. I have hooked battery up to a charger/another running tractor and also used bursts of ether in the air-intake. the ether gets it closer, but still doesn't make it past

the point of no return


is it possible the issue is maybe the oil air bath filter? the ether makes the most difference when i spray it down the air intake. i have cleaned out the oil bath bowl thingy really well - previously it was absolutely covered in thick, gross grime & grease, as well as the vertical inlet tube that the prefilter is attached to. just chunks and gobs of nasty crap like you wouldn't believe (or maybe you would)

I took them off and cleaned them off/out, soaked in diesel for a couple days, cleaned again, etc several times over. I also made sure to soak and wring that mesh part of the filter out as well, so i know it's clean. but maybe i added slightly too much oil and that's causing the engine to choke itself out? or maybe too heavy of oil? manual says SAE 20 i believe, but i only had SAE 30 around.

 

[caterpillar guy]

Oil should be only filled to the indented line around the cup on the bottom. You are fine with 30 in it for now. Sounds like you are off time since it doesn't start yet wants to hit on cylinders. OR you are not getting enough heat from the glow plugs and even without what has been said about the loosening of the little timing cover on the side it should still start for a minute then would shut down due to the pressure mentioned. It also so sounds like you may not have gotten all the air out if you changed the filters. Bleed from the fitrst filter to the second or to the pump whichever is next in line then follow it on to the injectors. Loosen the lines or bleeders at the injectors so fuel will come out at the injectors and you should be good to go on the fuel part of it. Glow plugs only need to be on for a short time like a minute or less . Not on all the time while running it will burn them out and are costly to replace now days. I would check them for getting warm on a battery individually by touching them to a couple of wires and see if they warm up or not. Then you need to follow them down the line on the tractor to see that you have juice to each of them with the wires on them. Do not spray either while using the glow plugs. IT is a good way to have issues with combustion causing bad things to happen.

 

[BarnyardEngineering]

my dad just had it rebuilt last year. for the second time actually, in the past few years. are these injector pumps/tractors known to be garbage, or easily damaged somehow?

also, it seems what you're describing is just or similar to bleeding the system of air? I've replaced the fuel filter cartridge, and bled the system and fuel leaks out of the pump/lines just fine.

maybe i should be more specific, the tractor doesn't fully turn on. it gets to the point where it seems like it's just on the edge of fully turning over (to when you would then stop pressing the starter button), but then it just sortof weakens, more and more until you stop pressing the ignition button. I have hooked battery up to a charger/another running tractor and also used bursts of ether in the air-intake. the ether gets it closer, but still doesn't make it past

the point of no return


is it possible the issue is maybe the oil air bath filter? the ether makes the most difference when i spray it down the air intake. i have cleaned out the oil bath bowl thingy really well - previously it was absolutely covered in thick, gross grime & grease, as well as the vertical inlet tube that the prefilter is attached to. just chunks and gobs of nasty crap like you wouldn't believe (or maybe you would)

I took them off and cleaned them off/out, soaked in diesel for a couple days, cleaned again, etc several times over. I also made sure to soak and wring that mesh part of the filter out as well, so i know it's clean. but maybe i added slightly too much oil and that's causing the engine to choke itself out? or maybe too heavy of oil? manual says SAE 20 i believe, but i only had SAE 30 around.

It's not the air cleaner, especially if it ever ran. To prove it to yourself, disconnect it and try starting the engine. You will not hurt the engine by running it for a few seconds without the air cleaner.

The injection pumps on these tractors are very robust and long-lasting, but if someone inexperienced worked on the pump without supervision, they could have easily introduced contamination, put it together incorrectly, or didn't replace a part that needed replacing. That would result in an early failure of the pump. The pump also needs to be installed correctly, and good clean dry (as in no water) fuel needs to be used.

Ether should not be used with this style of diesel engine, with pre-ignition chambers and glow plugs. Ether + red hot glow plug = BOOM. You can damage the pre-ignition chambers. At this point, if ether doesn't make it run, stop using ether.

The problem is with your pump, or its installation. What, exactly, that is, there is no way to know without being there.