Glow Plugs Don't Come On ('83 K30)

[cwlehner]

Last Thursday I had one of those exceptionally long days at the office and was the last one out. Looking forward to finally getting home, I hope in the truck, hit the key and .... nothing! No glow plug light, no solenoid sound, the engine cranked just fine though. It was about 30 degrees out, dark, and of course no one was around. I tried cycling the ignition about 20 times and finally gave up. I jiggled all kinds of wires, checked all of the fuses, etc.. Get back in the truck, and on the second try the plugs light up. Fortunately it didn't leave me stranded, but now I am semi worried that it will. First off, any ideas as to what happened, second will bypassing the solenoid fire the plugs? Any tips, tricks, or technical information would be appreciated.

Thanks, Chad

[rthomse]

1st thing I'd look at would be the ignition switch. Not the lock mind you the one on the collum under the dash.

[Xtpher]

I had a similar issue and found that the glow plug inhibit switch connection on the back of the block on the passenger side was dirty. I cleaned it up and that seemed to take care of the problem. Hope this helps.

[britannic]

Might be time to upgrade to the later glow plug controller. Our work flatbed had the old style that plugs into the head, it finally quit, so we're converting it to the later type (NAPA p/n AR145), which we'll mount on the driver side fender.

[Larry Andrews]

Is a symptom of controller failure that the controller thinks the motor is hot when it's only run for a mile or so?

I realize that you don't want to cycle the plugs unnecessarily, but it really sucks to be stuck someplace for an hour waiting for the thing to cool to /frozen/ before the dumb thing starts.

[TimK]

Chad,

I had the same thing happen to me on my 83 Suburban. On my truck there was a glow plug relay mounted on the drivers side inner fender. This eventually went bad. It started out where it periodically would not come on and then one day (while at a Christmas party) it didn't come on at all. The relay mounted on the fender isn't too expensive. You might want to throw an new in the tool box. The only way to diagnose the problem is when it doesn't work. If you have a 12volt test light/probe or a volt meter, you need to check for voltage when it fails. The next time this happens, check the voltage at the relay. You should have two heavy lugs and 1 or 2 smaller lugs. The one heavy lug is connected to the battery. It should read 12 volts or your probe will light up. The other side is connected to the glow plug wires. You will only see 12volts here when the relay is activated. The glow light on the dash turns on the same time when you see 12volts on this side of the relay. The smaller lug will see 12 volts when the controller tells it turn on. If you are seeing 12 volts on the smaller lug and not at both of the larger lugs, then your relay is bad.

TimK

[cwlehner]

In an emergency situation, can you bypasss the relay for a short time to fire the plugs and at least get it home. (BTW I just replaced the ignition switch on the column so I am pretty sure that is OK)

Thanks for all of the help!
Chad

[TimK]

Yes, If the relay is what is not working, you can bypass it for a brief amount of time. Keep in mind that a lot of current get's pulled through the relay. What every you use to jumper across the relay has to handle the current. Not just the wire size but whatever you are using that will make the contact will see a lot of current and a bad connection will heat up quickly. You also do not want to leave it jumpered for too long. The next time you start the truck count how many seconds the glow plug light is on before it cycles off. An extra second or two may not hurt but depending on the type of glow plugs you are using they may swell excessively or break if left on too long.

Using one side from a set of jumper cables may work.

If I was stuck on the side of the road, I sure as hell would try this.

TimK

[jcomp]

I know this isn't the most popular answer in this forum, but I LOVE my manual GP setup.

[britannic]

With 60G glowplugs, you just have worry about a bit more drain snd strain on the GP solenoid with the earlier GP setup if you run them longer than normal.

The 60G has thermal protection built in, and "More Power" wrote a feature article about how they held up for many hours without failure whilst glowing red hot.

[HammerWerf]

cw
when my relay went outin my 1983 CC, I jumpered from the positive side of the battery to the Glowplug side of the relay. Glow plug light glowed during this operation. I used a 18inch 10awg wire. Counted to about 6 sec, started every time. MAke sure your connections are solid. Had replaced the relay when it first failed (21yrs old), but the new one would not pull in. Recent GP jump in a rain seems to have fixed the non pull in.

HammerWerf

[cwlehner]

Originally posted by Xtpher:
I had a similar issue and found that the glow plug inhibit switch connection on the back of the block on the passenger side was dirty. I cleaned it up and that seemed to take care of the problem. Hope this helps.

Went looking for this and not sure if I found it.. Is this literally on the back of the block, or on the side towards the back? Any help figuring out where this is would be appreciated.

[rthomse]

Looking at the engine from the front its on the left side, back by the firewall . You'll see the wiring harness going to the glow plugs follow it back ,you'll see the two wires,mine are light and medium green comming from the harness to a conector.The switch look just like a temperature sending unit.Hope this helps.

[cwlehner]

Well...

I cleaned up the thermal switch, and now the system has entirely different issues. Now when I start it cold, the solenoid comes on for about 10 seconds and then shuts off. Then it continues to cycle in one second intervals aproximately 6 or 7 times (regardless whether or not the trucks is running). Also the glow plugs come on randomly while driving, exhibiting a similar pattern to what I just described. Sometimes the starts are normal (2 or 3 10 second intervals and it starts), but most of the time itis acting funky.

I have a new solenoid ordered as well as 60G plugs (I do not want them to swell!!). Is my controller bad, if so what is the preffered method for making the system manual? Should I consider the NAPA updated glow controller?? I don't want to spend a lot of money..

Thanks, Chad

Thanks, Chad

[Brianlar]

A nine dollar ford starter relay, solenoid, a three dollar horn button, and some wire. Versus the Napa GPC, $100.00, Hmmm, Ford rules.

[dieselcrawler]

Originally posted by Brianlar:
Hmmm, Ford rules.

Bold words, I'd say, for a Chevy-based forum... *grin*

I have manual GP switches on both my trucks, wouldn't have it any other way. Theft deterent, (keeps wiseass friends from thinking they can just move my truck anytime they want) and they work when I want them to, and only then.

Good luck all...

Greg

[ZZ]

I remember in my GM 5.7L Diesel days that I bought a Ford starter solenoid and a spring loaded toggle switch. I held the switch for 6 seconds with 8g's or 30 to 45 seconds with 7g's

[C.K. Piquup]

As far as the fender mounted relay on the early,non-solid-state set-ups,like other relays,if it don`t click,it must be sick.If no click,see if power is getting to it.If it is,then it`s the relay.If it does click,it`ll be the controller.I think just`84s had the inhibit switch.But,if yours does have one,could be that.Again see if power is getting to it.It helps to have an ohm-meter & Helm manual.