***!!!!

[dyoung14]

I bought 8 brand spanking new glow plugs from rock auto and 2 cranks later all freikien 8 of them are burnt up! Whats going on

 

[FordGuy100]

***?

What do you mean? Did you glow plug controller fail on you?

 

[dyoung14]

i had them hooked up manually off a push button, the 2 times i started it i never held the button longer than 10 seconds

 

[FordGuy100]

Take them out...clean them up...and send them back.

 

[dyoung14]

Take them out...clean them up...and send them back.

im going to call them either tonight or tomarrow

 

[The Warden]

What brand are they? And IIRC 8 seconds is the upper safe limit?

 

[dyoung14]

motocraft beru, and i thought it was fine to glow like 10-15 seconds cause my other truck with the factory glow controller would hold 15+ and it never burned any up the hole 2 years i had it

 

[FordGuy100]

I stick to 8 seconds when temps are above 50*, and vary as it gets colder.

 

[dyoung14]

well it was like 35 the 2 times i cranked it with them so...

 

[65sixbanger]

maybe do two cycles of eight seconds....

 

[The Warden]

maybe do two cycles of eight seconds....

That's what I did when I had a manual push-button. I would go 8 on, 8 off, 8 on, and then crank. Sometimes I had to cycle a few more times. Even still, I would accidentally run them a bit too long and ended up killing a few sets of plugs before abandoning the manual setup.

The biggest thing to keep in mind with these plugs is that, assuming you're using stock plugs, they're 6 volt plugs with 12 volts being applied to them. That's why it's so easy to burn them out. The 7.3l controller, when working properly, can sense how hot the plugs are and know exactly when to cycle them on and off...the problem is when the controller starts acting up, or when connections get corroded (the controller senses resistance on the line and works the system accordingly). I swapped to a 7.3l system and made the mistake of making my own wiring harness and not realizing how sensitive the controller is to resistance, so my system's never worked properly...I plan to repair it, but for now, I'm just using the key to cycle (the controller will burn the plugs for about a second before shutting off, and then I wait 10 seconds...4 or 5 cycles like this and the truck will start)...of course, the 6.9l bimetallic spring controller's a joke...

 

[82F100SWB]

Personally, I think the re-cycling the plugs is what is hardest on them. I have burnt the Wellmans in my 6.9 well past 30 seconds on many occasions in the mid -20's, and in 3 years, I've had 2 fail. With the stock controller, I burnt up 3 Berus in the first winter I had the truck.

 

[Diesel JD]

First thing I'd wonder about is your timing, however even with very advanced timing it usually takes a long time to eat them up. I don't really see 10 seconds on the manual controller as excessive. I really like runaway's idea of using the 12V AC Delco plugs from the 1978-80 olds 5.7 with a manual controller if you can get those plugs cheap anywhere. I killed a set from over advanced timing but I was 2 teeth too far on the gear and probably damaging other things...just more slowly, and these still lasted for months. After I got the timing straightened out I never burnt up another glow plug with the manual controller, I just swapped to the 7.3 system because occaisonally someone else works on or drives my truck and I was paranoid about something happening. I've had the same set of glow plugs in there for 5 years since I did the conversion minus one plug that failed on me about 2 years ago. (Why did it have to be the one right under the turbo)?

 

[6 Nebraska IDIs]

maybe do two cycles of eight seconds....

That is the worst possible thing you could do to them. My mom does that and I get to replace her glow plugs atleast 3 or 4 times during the winter months.
I glow plug my brown truck 10 seconds during the summer mornings, and 12 in the spring and fall when temps are above ~20* below 20* I'll go 14 and below -20 I'll go 16. I have never had a problem doing this. The glow plugs in that motor are the same ones that were in it when I bought the truck several years ago.
Something ain't right with those GP's. I have never heard of all 8 burning up in two cycles.

 

[85hauler]

I have never heard of all 8 burning up in two cycles.

A few years back I had a set of Berus last 3 starts in the "Hauler". Manual setup, held 10 seconds each start. 4th time I went to start the truck all 8 were burned out. One of those Berus (#8) lost the tip in the cylinder. That's the only tip I've ever lost.