87 IDI glow plug issues

[NIDiesel]

I've got a 87 Ford F-350 with a 7.3 IDI. Needed a set of glow plugs, put in 8 glow plugs and a relay, wait to start light worked like it should, truck started good for about a week. Truck started starting hard (it 80 degrees out at the time.) Ended up putting another set of glow plugs in, still not working right. Relay just continually clicks for about 30 seconds. Went to NAPA got a new glow plug relay and controller, put it on, that one does nothing. No clicks, no WTS light, nothing. On a bench I can hook 12 volts up to the solenoid, hook a 12 exciter wire, I get 12.31 volts going to the solenoid and I get the same coming out. As soon as I hook up the ground the output drops 10.75 volts on both new and old relay/controller set up. My output for the WTS light is 12 volts until I hook up the ground, with the old setup it drops to 7.8 volts and the brand new one drops to 4.2 volts. When the old one clicks I would check voltage and its in and out with every click. Unplugged all the glow plugs and it still clicks, unhooked the glow plug harness from the relay and it still just clicks for 30 seconds or so. The new setup is still junk and doesn't do anything. And i understand that new doesn't mean it works. I guess I'm just wondering if I need to try another new controller/relay setup, if I need to try something else, or just go get a stick of dynamite. At this point I'm open to any suggestions.

 

[snicklas]

What brand of plugs are you using? Is the ground for the controller and all electrical connections bright and clean? The controller is sensitive to baf connections. Depending on brand the new plugs may be bad.....

 

[NIDiesel]

I put Autolite glow plugs in it. New development, had the old setup on so I could do some more tests, had the key on clicking went on about the normal length of time then quit. I went to test some power and when I touched the relay it burned my fingers, took it off and the controller got melted from the relay being so hot. I ordered a new relay/controller from Ford, gonna get rid of the Napa junk, I've always been told to stay away from Napa electronics, but they had one and no one did so I got it.

 

[Fordfan90]

I put Autolite glow plugs in it. New development, had the old setup on so I could do some more tests, had the key on clicking went on about the normal length of time then quit. I went to test some power and when I touched the relay it burned my fingers, took it off and the controller got melted from the relay being so hot. I ordered a new relay/controller from Ford, gonna get rid of the Napa junk, I've always been told to stay away from Napa electronics, but they had one and no one did so I got it.

You should only use zd9 glow plugs. I had an autolite swell and break off in the head once. Not fun getting it out.

 

[chris142]

Also. There is a gray electrical plug on the passenger fender. All the glow plugs ,alternator etc go through it and it burns up.

 

[riotwarrior]

Motorcraft beru zd9 plugs only....no other brand!!!

 

[NIDiesel]

The connector on the fender has already melted and been fixed. All the wires run through a new one except for the two glow plug wires. They are hooked straight together outside of the plug all on their own. I got Autolite plugs because I was always told that Autolite made Motorcraft parts, actually I believe Honeywell makes the plugs for them both, maybe the Motorcraft ones have to be made to a higher spec. Not saying they are the same, that's just the impression I was under. Any Ford I've ever owned has always had or been replaced with Autolite plugs (not glow plugs, just spark plugs mind you), but I've never had a problem with them.

 

[DaveBen]

Beru or Motorcraft ONLY. No matter what you think, Autolight is junk in glow plugs. I like the Autolight spark plugs.