My GP Controller Blew up

[84TD]

Yesterday morning I went out and started my truck like normal but when I came back out to leave my truck was off and I could smell burning plastic smells. I poped the hood and quickly found that the blue fusible link connected to the R/G wire was smoked. I had fusible link problems before so I thought it was just that. Stopped at the parts store and got an inline fuse holder and went home and hooked it up in place of the link... kept poping fuses. So I went to the wire diagram and looked at what all was in that circuit so I could start unpluging stuff. When I got to the controller it looked like it does... Any ideas why it would do that? Just old? I am afraid of buying a new one for 80 bucks and it doing the same thing if something is wrong.

 

[84TD]

Is it better to use motocraft? It looks like the moto one is aluminum, Advanve has the Niehoff Ignition Glow Plug Controller, never heard of them before.

 

[PnrFab]

never buy Niehoff parts! i have had so much trouble with their parts and so have my friends. i would look at dealr or maybe a napa or carquest.

-josh

 

[Dsl_Dog_Treat]

If it's any consolation, I replaced a Motorcraft one that was exactly identical to the Napa brand controller. Same sticker and all.
That one you have definitly doesn't look very good.

It may be possible that corrosion took it out, not sure there.

 

[Diesel JD]

Those old latching relay/screw in head controllers were notorious for blowing up...burning out plugs..just not working period. You should either setup a manual switch with a momentary toggle or get the solid state upgrade wiring harness and controller from IH. My opinion is that fixing the 6.9 system is spending good money after bad. Also, you might want to be careful to bring the cylinder you are working on to TDC before you remove any burned out glow plugs, so you can give yourself a chance to suck out any broken off tips with a vaccum through the injector hole. Before you go pulling the plugs make sure they are bad...a simple test with a test light for continuity is always good enough on the 6.9 plugs/system. You might also read Ziggster's webpage on GP removal. Good luck,
J.D.

 

[84TD]

Thanks JD, I will try to fix my system tho, if I keep having to dump money and time into it then I will bypass it. After much searching I was able to find a controller at a decent price from Delco Diesel Services Inc, 1100 S Agnew Ave, Oklahoma City, OK (405) 232-3595. They have an ebay store (delcodiesel) with some pretty good deals on GP stuff. Well I got a Motorcraft Gp controller from them for 30 bucks plus shipping. Not too bad. Ill see how it works on Friday when I get it.

 

[Diesel JD]

Hey I think agnem has something to make the latching relay a little less likely to blow up yet still retain the factory functionality. Have a good one,
J.D.

 

[84TD]

I got the controller in and found out it had taken the relay out as well. So I bought a new one. The GP light comes on and I have verified voltage at all the Glow Plugs, however I am not fully convinced my system is 100%. Still a bit harder to start since before this happened.

Is it possible for a GP to pass the testlight test and still be bad?
I am talking about the one where you put the lead on the + and probe the GPs without the harness hooked up and see if it makes circuit.

 

[Dsl_Dog_Treat]

JR,
I did find that one of the GP's I had tested did light dimmer that the other good ones so yep it's possible.

 

[84TD]

I am convinced now, it is a bit colder than it has been today. I just went outside and had to use ether to get my truck to start. All the right voltages are there, all 8 plugs pass the light test, all 8 are getting 12v when the controler kicks on.

Is it possible that when my controler went haywire it took out all the plugs?

Another thing I noticed, After the initail 13 sec GP ontime, if you cycle the ignition it will do it again for another 13sec. It used to do it for only maybe 2~3 sec the second time.

Thoughts?

 

[Agnem]

Depending on how soon that second 13 seconds comes in, that could toast your plugs. Try this... with a cold motor, slip a 30 gauge wire under the conector of one of the glow plugs and put the connector back on. Now you have a test point. Connect a volt meter to the test point, and ground. You should see the voltage down around 6 volts and slowly climb towards battery voltage as the glow plugs heat. If you're at 10 or over right off the bat, I'd suspect bad glow plugs.

 

[Diesel JD]

I hope you didn't use ether along with the glow plugs!! That would be bad. They will often ignite the ether before you can turn the motor over. Its really much better to go to the solid state system or the manual glow plugs. I don't like the latching relay...too many failures over the years.

 

[84TD]

Dont worry fellas, I unplug the relay before I use ether....

I have battery voltage (+/- 12v) at all my Glow Plugs as soon as the relay clicks on.

Its suppused to have lower voltage and rise up to it?

 

[f-two-fiddy]

Yeah, the Spade type GP's are only 6 V.

It should start @ 6V When the connector is attatched to the GP. Slide your test meter probe down inside the connex while all are attatched to the GP's. Then hit the ON switch. You'll get the proper readings, then.

The latching type are resistance controlled. The higher the reisistance, the colder the engine is.

 

[84TD]

Yeah, the Spade type GP's are only 6 V.

It should start @ 6V When the connector is attatched to the GP. Slide your test meter probe down inside the connex while all are attatched to the GP's. Then hit the ON switch. You'll get the proper readings, then.

The latching type are resistance controlled. The higher the reisistance, the colder the engine is.

I am sliding my meter pos lead into the connector with them all hooked up and the neg lead on the batt ground. As soon as the controller turns the relay on I have 12+vdc there. Should I suspect the controller on and the gps all shorted to ground so they are getting the full 12v?