Glow plug carnage!

[Sycostang67]

I replaced my glow plugs yesterday and decided to have some fun with the old ones. I'm kind of surprised my truck cold started at all. The 6 plugs I pulled tested good with a test light, but 2 of them didn't get warm at all, the other 3 burned once and never again, and the 6th one did this.

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This was an autolite 1108 after 15 seconds with a weak battery I had sitting in my garage the last few months. I assume the other bad glow plugs kept my controller from letting it get to hot.

 

[Alex S]

The people over at Autolite should be shot at dawn

 

[Andylad13]

The same thing happened to mine when I hooked them up to a battery. Some sort of growth-thing that wont come off unless you file it down! Its bad enough hooking them up to the resisted controller. When you hook it up to 12V, your just asking for trouble.

 

[JwS]

I had a similar experience when I first got my van, all the plugs checked out OK, but still didn't seem to be working right. So finally I replaced them and it was clear that some or all were NG. So I don't trust the meter or test light tests, they don't seem to give the whole picture.
JwS

 

[vikurt2002]

Did you have any trouble getting the old ones out? I know I have two bad glow plugs and it starts hard when the temperatures are low if I don't plug it in. I'm not really wanting to pull the heads to get the glow plugs out though.

 

[f-two-fiddy]

It is odd how resistance heaters work.

We had a nice Bunn coffee maker. It started to trip the GFI outlet when We brewed a pot. So I got the MM out and everything checked out OK. I tried again, same effect.

So I tore it down. The heater element inside the water tank was in tact, But it had burned almost all of its ceramic carrier off. The heater wire was just dangling around in the water

Very strange that it would actually heat the water. But it did.

 

[Agnem]

Shorting electricity through water to a metal canister is definitely a good way to test your GFI.

 

[firemedicmonkey]

Is there an article on testing glow plugs? I am wondering if I have some bad ones on the truck I just bought... it is hard starting... and has no block heater that I can find...

 

[Sycostang67]

Did you have any trouble getting the old ones out? I know I have two bad glow plugs and it starts hard when the temperatures are low if I don't plug it in. I'm not really wanting to pull the heads to get the glow plugs out though.

I had two that fought me a little bit, but I soaked them with PB blaster and wiggled them out. I think it was mostly just built up soot holding them in though. They were the plugs that didn't light up at all when hooked to the battery.

 

[mankypro]

Would testing gp's on a 12v battery for 5 seconds for burn shorten their useful lives?