Glow Plug Test

[TLBREWER]

Is there a way to check glow plugs when not installed? Seems I read something a while back about checking resistance, but can't find it now. I replaced all of the GP's during head rebuild on my wifes truck, but I don't want to throw the old ones away if they're good (believe 2 are bad). Shoulda checked them before taking everything apart.

Tom

 

[RKOCH]

Take a heavy jumpper wire w clips. Clip it in the treads of the plug connect the other end to the neg side of a battery. Holding the plug by the clip do not touch the tip!!! Touch it on the pos side of the battery. If it is not glowing red in just a few short seconds trash it. This is the only way I check them resitance is not worth a crap.

 

[TLBREWER]

Thanks. I thought about doing the exact thing you described on my way home from work this morning.

Tom

 

[F350camper]

Yup, that's the best way to check them Tom. I've had one that passed the resistance test but never glowed. I guess the element inside broke but still shorted to ground making the plug useless, but able to pass the quick ohm test.

 

[TLBREWER]

There's my project for Saturday afternoon.

Tom