How do you test glow plugs?

[AJMBLAZER]

For a while now I've been suffering the symptoms of dead and dying glow plugs. Hard starts, lots of cranking, runs fine once going but starting is a bitch, etc.

So about two weeks ago it just wouldn't start. Turned right over thanks to the two new 31 series 1000+ amp batteries but just wouldn't catch and start for anything. Had to leave the garage door open it smelled like diesel in there so bad.
Thought it might have been the cold weather that day so I left it.
Next day it was 60+ degrees and no change.

Got some new Wellman 070's and am going to install them today but I'm just wondering how do I test the old glow plugs to see if they're still in working order. I think someone on here mentioned it before.
I'm betting they're all dead.

 

[tRustyK5]

Simple to test with a test light. Attach the clip to the + side of the battery and touch the probe of the test light to the GP spade. Light comes on the glow plug is likely good (95% likely, there are some exceptions). This would be with the glow plugs still in the engine BTW.

No light, GP is deader than a doornail.

Very quick and easy.

Rene

 

[AJMBLAZER]

Well, they're all sitting on the floor now with the new Wellman 070's in. Luckily it seems that the military put Wellman 070's in last time as well as there was no swelling on any of them and they all came right out.

So how's the test go for sitting on the ground, out of the vehicle?

 

[redneckdude]

Well, they're all sitting on the floor now with the new Wellman 070's in. Luckily it seems that the military put Wellman 070's in last time as well as there was no swelling on any of them and they all came right out.

So how's the test go for sitting on the ground, out of the vehicle?

i would imagine if you grounded it back to the battery and did the same test light deal as mentioned above, it would work the same. You are just seeing if it conducts current through it.

 

[tRustyK5]

Yup...safer than using jumper cables

So, does it start better now?

rene

 

[kennyw]

Also, with the 24 volt system, when one fails they all fail shortly after if you don't get it fixed right away. The voltage goes up with everyone that fails because of the resistor being used to drop the voltage from 24 to 12.

 

[AJMBLAZER]

Does it start better? Hah!

You'd think it was a Gasser with a MSD system or something. Glow plug light goes out, half throttle, turn the key and VAROOOOOOMRATTLE! It starts.