Author Topic: Going through glow plugs like CRAZY  (Read 7817 times)

March 30, 2007, 12:25:44 pm

addautomotive

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Going through glow plugs like CRAZY
« on: March 30, 2007, 12:25:44 pm »
In the past 2 months, I have changed 7 glow plugs in my samurai.

There is no rhyme or reason, they just die. They aren't burnt or show damage from a bad injector. When I pull them, they are just black.

And it's never the same one... it seems completely random.

It is not a relay issue; I have them run through a solenoid activated by a pushbutton. They are never on longer than 10-15 seconds.

What gives? Anyone have any ideas why I'd be going through glow plugs like this.

Reply #1March 30, 2007, 12:33:55 pm

burn_your_money

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« Reply #1 on: March 30, 2007, 12:33:55 pm »
Is it not normal for them to turn black? Do they still get hot when you hook them up to power?
Tyler

Reply #2March 30, 2007, 01:28:47 pm

addautomotive

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Going through glow plugs like CRAZY
« Reply #2 on: March 30, 2007, 01:28:47 pm »
Quote from: "burn_your_money"
Is it not normal for them to turn black?


Kinda sorta. These guys are just completely black without any heat lines or anything.

Quote from: "burn_your_money"
Do they still get hot when you hook them up to power?
Nope, not even a spark when you hook them up to a wire. Draws 0 amps. Dead. Gone. Kaput

Reply #3March 30, 2007, 01:42:00 pm

saurkraut

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Going through glow plugs like CRAZY
« Reply #3 on: March 30, 2007, 01:42:00 pm »
I wonder if your solenoid is hanging up and keeping them energized.
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Reply #4March 30, 2007, 02:14:39 pm

addautomotive

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Going through glow plugs like CRAZY
« Reply #4 on: March 30, 2007, 02:14:39 pm »
Nope, I have an indicator light hooked up to the #1 plug, so I always see when they are getting juice.

I wish it was something as simple as that

Reply #5March 30, 2007, 02:43:36 pm

dieselsnowmobile

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Going through glow plugs like CRAZY
« Reply #5 on: March 30, 2007, 02:43:36 pm »
What kind of glow plugs are you using?  Champion glow plugs are crap.  Only use Bosch.
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Reply #6March 30, 2007, 03:14:08 pm

addautomotive

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Going through glow plugs like CRAZY
« Reply #6 on: March 30, 2007, 03:14:08 pm »
Well, I have some Bosch and some VSP. Doesn't seem to make a difference.

Reply #7March 30, 2007, 03:21:40 pm

jimfoo

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Going through glow plugs like CRAZY
« Reply #7 on: March 30, 2007, 03:21:40 pm »
Have you measured the voltage at them when they are on to see if it is normal?
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Reply #8March 30, 2007, 03:59:14 pm

addautomotive

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Going through glow plugs like CRAZY
« Reply #8 on: March 30, 2007, 03:59:14 pm »
Quote from: "jimfoo"
Have you measured the voltage at them when they are on to see if it is normal?


No, I haven't... hmm

Now, here's something else a bit different in my setup... each plug has a heavy individual wire going to it. Makes it much easier to pinpoint which plug is dead. I've used the same setup in all my diesels and never had a problem, and I can't imagine it would cause this problem.

Reply #9March 30, 2007, 08:02:27 pm

jtanguay

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Going through glow plugs like CRAZY
« Reply #9 on: March 30, 2007, 08:02:27 pm »
Quote from: "addautomotive"
Quote from: "jimfoo"
Have you measured the voltage at them when they are on to see if it is normal?


No, I haven't... hmm

Now, here's something else a bit different in my setup... each plug has a heavy individual wire going to it. Makes it much easier to pinpoint which plug is dead. I've used the same setup in all my diesels and never had a problem, and I can't imagine it would cause this problem.


i myself can't see individual wires going to the GP's destroying them.  I know that on Toyota diesels the GP's don't use 12 volts, and will be destroyed if you try to connect them directly to the battery.  I think they were 5-6 volts or something.  our gp's can withstand 12 volts for sure... maybe you have bad luck with the gp's???


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Reply #10March 30, 2007, 08:40:37 pm

Vincent Waldon

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Going through glow plugs like CRAZY
« Reply #10 on: March 30, 2007, 08:40:37 pm »
Over torquing when installing them can have very detrimental effect on their lifespan because it compresses the resistive element... don't have my Bentley handy but I've read in several sources not to overdo it... something to check with a torque wrench the next time you are changing them perhaps ??

Vince
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Reply #11March 31, 2007, 04:36:37 am

addautomotive

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Going through glow plugs like CRAZY
« Reply #11 on: March 31, 2007, 04:36:37 am »
Thanks for the help guys!

Quote from: "Vincent Waldon"
Over torquing when installing them can have very detrimental effect on their lifespan because it compresses the resistive element... don't have my Bentley handy but I've read in several sources not to overdo it... something to check with a torque wrench the next time you are changing them perhaps ??

Vince


You know, you could be on to something. I put them in pretty tight, and perhaps I'm overtightening the 8mm nut too, I suppose that could twist and damage the element.

Reply #12March 31, 2007, 07:48:26 am

burn_your_money

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« Reply #12 on: March 31, 2007, 07:48:26 am »
thanks for the over tightening tip, I'm doing GPs today and that is not a job I'd want to do twice
Tyler

Reply #13March 31, 2007, 12:31:13 pm

Vincent Waldon

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Going through glow plugs like CRAZY
« Reply #13 on: March 31, 2007, 12:31:13 pm »
There are a few (and only a few) instances where my diesel is more of a pain than my gasser... and changing the glow plugs is one of them !!
Vince

Edmonton, Alberta, Canada
2001 silver TDI Jetta Malone Stage 1.5 , 2001 blue TDI Jetta SBIII 216s Malone Stage 3, 1970 Bay Window bus

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Reply #14March 31, 2007, 01:38:42 pm

addautomotive

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Going through glow plugs like CRAZY
« Reply #14 on: March 31, 2007, 01:38:42 pm »
You bet, but I've sure had lots of practice lately!

I can even do those two behind the injection pump without taking off the injector lines. Only takes me 20-30 minutes now.

Magic trick is the grease on the 8mm wrench. Keeps them from sliding off!