All righty, here's a stumper for y'all. The truck in question is a 1983 F250 2WD with a 6.9l diesel and an automatic trans. Has every option available except A/C.

The truck would not start one morning a couple months ago, so I began to suspect the glow plugs. A previous owner had already wired up the pushbutton. so I didn't even have to go that far with it...it was already done. So I went and got the 1st set of glow plugs I could find. They lasted approx. 1 month. I got another set of glow plugs from the same parts store, but this time I went with the Bosch brand. This set lasted 5 weeks. What gives???

Let me answer ahead of time some of the questions I can see coming.

1. I never hold down the pushbutton for longer than 5 or six seconds
2. I checked and there is only power to the glow plugs when I hold down the pushbutton.
3. I made all the usual checks on the faulty glow plugs with a test light..they were faulty all right.
4. The wiring job on the pushbutton is neat and tidy. It uses wire that is heavy enough for the job and it is wired just like the diagram on Zigsters website. Hell, there's even a red alert light wired in just to let me know that I have my finger on the pushbutton!


One final question: Am I supposed to have a full 12 volts at the glow plug terminals, or is there a stepdown somewhere along the line that got overlooked?

Please help me out here folks.. really scratching my head here.

Thanks a bunch.

Tortoise

 

Is the wire from the original controller still hooked up to the relay on the fender well?
If it is the controller may be turning the plugs on while you are driving.
It was called "Afterglow" to reduce the white smoke after it started.
Mine did that till I unhooked the controller, that OEM wait to start light does not stand out well enough to catch your eye while driving.
I removed the controller connector and taped the plug up then wire tied it so it could not short out. I also removed the stock wire from the relay and only have the switch wire on the relay.

Also get Motorcraft/Beru glow plugs.
The glow plugs have 12 volts running to them.

 

Ah, yes! Another of those things that led me to appreciate gas engines. I had an '82 GMC 6.2 that went through 5 complete sets in 60,000 miles .... that's 40 glowplugs! It seems the fact that the timing was slightly out of whack ate the glowplugs ... something you might want to look at.

I also had an '84 & an '85 6.9 and had so much experience with it that I could tell the service people almost exactly how many plugs were out when I took it in for repairs (company trucks). The nature of the beast I guess ...

I'm glad Clyde is a 460" gasser. Good luck with it.

Roger