L245DT Glow Plug Indicator never glows

[tomasaur]

As long as I've had my 1982 L245DT, the glow plug indicator has never glowed. I've seen one glowing nicely in a video, but not mine, even when putting the juice to the plugs for 10-20 seconds.

I replaced the indicator a few years ago when I got the tractor, and have replaced the glow plugs as well, but... nothing. When I measure the voltage going into the indicator I read about 11.8v, even though the battery reads 12.5. On the output side of the indicator, it reads 9.8v. I'm assuming that the voltage drop across the indicator is because the indicator itself is a resistor of sorts. The voltage at the glow plugs themselves is also 9.8. I don't have a DC clamp ammeter to test the amperage going to the plugs.

So, I'm wondering if the fact that I'm not getting a full 12+v to the indictor makes a difference.

It's not a big deal, but I'm curious. Any thoughts?

 

[85Hokie]

Try it again.......... at dark or dim light and hold the key for 45 seconds.

If you have an infrared thermometer ............. point it at the indicator AS you turn your key

 

[North Idaho Wolfman]

On that model 45 seconds to a minute is required for the glow plugs to hit max and that's when the glow plug indicator will "glow".
Spray a little oil on it and watch it smoke.

If the tractors starting then the system is working.

 

[Russell King]

Your operation is normal. You will see it glow in dimmer light with longer glow times.

You will also get voltage to the glow plugs in the cranking switch position but that position bypasses the glow indicator.

 

[Mark_BX25D]

When I measure the voltage going into the indicator I read about 11.8v, even though the battery reads 12.5. On the output side of the indicator, it reads 9.8v. I'm assuming that the voltage drop across the indicator is because the indicator itself is a resistor of sorts.

That is correct.

 

[tomasaur]

Thank you everyone! I was thrown off by a video where a guy powered on the glow plugs and the indicator glowed within 3-4 seconds. Very good to know that the wait time is just longer than I'd been giving it.

 

[North Idaho Wolfman]

Thank you everyone! I was thrown off by a video where a guy powered on the glow plugs and the indicator glowed within 3-4 seconds. Very good to know that the wait time is just longer than I'd been giving it.

Yea on that model if you have, a glowing indicator in 3-4 seconds would mean you have a shorted glow plug.