Ford 1700 glow plug issues

[geozeitl]

Hello From snowy Green bay. Having issues with glow plugs burning out after a couple of starts. I did some looking around and l have about 9to10 volts going to the plugs when turning the key to the left. The indicator glows red. Question 1. Is it ok to leave a battery charger on the battery when heating up the plugs?Possible power surge?Question 2. Is it normal for the glow plugs to activate when starting(turning key all the way to the right)Question 3. Does the voltage regulator have anything to do with this?Any thoughts or ideas would be appreciated. Darn plugs are $15 a piece and dont want to go broke buying these

 

[Dave M7040]

Hello From snowy Green bay. Having issues with glow plugs burning out after a couple of starts. I did some looking around and l have about 9to10 volts going to the plugs when turning the key to the left. The indicator glows red. Question 1. Is it ok to leave a battery charger on the battery when heating up the plugs?Possible power surge?Question 2. Is it normal for the glow plugs to activate when starting(turning key all the way to the right)Question 3. Does the voltage regulator have anything to do with this?Any thoughts or ideas would be appreciated. Darn plugs are $15 a piece and dont want to go broke buying these

If glow plugs are burning out, something is clearly wrong.

Wiring changed leading to and between Glow plugs, wrong glow plugs. Some GP's are wired in series and most in parallel.

Battery charger is not causing this but if your battery is in poor condition, replace it before you damage the starter from excessive cranking.

Glow plugs should be on when the engine is cranking

Voltage regulator has no effect on GP's but on your battery.

If someone replaced the key switch and connected the wires incorrectly it could be the cause of your problem.

Study the attached schematic to see how, in preheat mode, the power to the GP's flows through the GP indicator but when cranking, the GP indicator is bypassed and the power flows only from terminal 17 directly to the GP's without passing through the indicator.

Dave M7040

 

[Roadworthy]

The voltage going to the glow plugs is probably correct - they are not a twelve volt device. Most run at about 10.5 volts. I, too, suspect a wiring problem. Once the tractor is started check to see if the glow plugs are still energized. They should not be. I once replaced my tractor's ignition switch with an automotive switch thinking I'd power the glow plugs from the accessory position. Bad choice. The glow plugs were then on whenever the ignition was on, too. I disconnected the glow plug wire and now feed it from a separate switch. The only way my glow plugs ever get power is when I activate that switch. If you go that route you should be aware the switch should be capable of handling a decent amount of current - figure ten amps per glow plug. My switch is rated at fifty amps and it's spring loaded to the off position.

 

[geozeitl]

First off all thanks for replying that's awesome. I just have a trickle charger on the battery to keep it fresh.when not in use but l leave it on when l start it. I did check with my meter when turning the key to the left the indicator glows and power about 10 volts is at the plug. When turning all the way to the right(start position) indicator does not glow but 10 volts at plug. When at the run position no power to the plugs, I think that is correct

 

[Roadworthy]

The normal status of glow plugs is without power. Their only function is heating the head during starting. If yours are continually burning out it indicates they get power somehow when they should not or they are not the correct plugs. I purchased my Mitsubishi used. The glow plug indicator had been bypassed and the glow plugs were of the wrong type. The indicator was pretty obvious. I used the tractor ten years before learning it had the wrong glow plugs. If you can rig a way to monitor your glow plug voltage that would help isolate your problem. I suspect something is energizing them when it should not. The indicator is in series with them so it glows when dropping the supplied voltage. I suspect there is an alternate path powering the glow plugs. If the indicator is not on during those times they are getting the full twelve volts. A meter on the plugs would be good but even a twelve volt lamp can act as a tattle tale.

 

[geozeitl]

The normal status of glow plugs is without power. Their only function is heating the head during starting. If yours are continually burning out it indicates they get power somehow when they should not or they are not the correct plugs. I purchased my Mitsubishi used. The glow plug indicator had been bypassed and the glow plugs were of the wrong type. The indicator was pretty obvious. I used the tractor ten years before learning it had the wrong glow plugs. If you can rig a way to monitor your glow plug voltage that would help isolate your problem. I suspect something is energizing them when it should not. The indicator is in series with them so it glows when dropping the supplied voltage. I suspect there is an alternate path powering the glow plugs. If the indicator is not on during those times they are getting the full twelve volts. A meter on the plugs would be good but even a twelve volt lamp can act as a tattle tale.

Thanks for all the advice I will check it out and will post if l find anything obvious

 

[geozeitl]

Thanks for all the advice I will check it out and will post if l find anything obvious

Hello again, Im no electrician but I did check to see if i did have power going to the glow plugs when the tractor was running. On my fluke meter it reads 0.013 for dc voltage I connected it to the wire spade that that goes on the spark plug. Would that be enough to burn out the plug?

 

[Dave M7040]

I would be more comfortable if you bought and used a 12 volt test light worth about $10.

Do not go touching your Fluke meter to any spark plug Obviously you meant to say Glow Plug.

It is a simple yes or no test with no issues with meter scale or other settings.

Amazon.com: IIT 261 Professional 6-12V Circuit Tester - Indicator Light by Industrial Tools: Automotive

Dave M7040

 

[geozeitl]

Sounds good will check it out

 

[geozeitl]

Well after buying a circuit tester everything tested ok.starting to wonder if too much fuel getting on the tips of the glow plugs and burning them out. This tractor is cold blooded and have to crank 2 to 3 times to get it going.