83 to 85+ Glow Plug Controller help needed....

[ordiesel]

Back ground: I'm new to Diesels and have been re-wiring some of the wires in the '83 C2500 Suburban I recently purchased (the wires running to the starter melted onto the exhaust manifold and shorted the harness). It was previously converted to the 85+ glow plug controller. The wiring appears to have been nicely done and the harness was extended to the controller now sits on the driver's side inner fender.

I traced all the wires from the new controller to the harness to make sure where they went.[LIST=1]
Terminal A is not used.
Terminal B connects to the

[ordiesel]

Gee thanks for all the replies. It was over whelming. I got my issue resolved.

[Subzilla]

We're glad you resolved your issue but don't be so hard or sarcastic on us. You will not find another forum with as much experience and knowledge as the fine folks here on the Page. These guys will try to help as much as possible but sometimes there may be a lull in the responses. I've submitted questions that generated 20 replies and other times may have only gotten one response. I didn't go away pouting but rather just figured everybody was out enjoying the weather in their diesels. Plus you won't get the immature blasting or criticizing here like you do on other sites. Give us another chance before you go making a final judgement on us.

And welcome to the forum!

[john8662]

Out of curiousity, what ended up being the issue with the flickering glow light?

This could be helpfull for future troubleshooting for other members.

J

[ordiesel]

Yeah, that was my bad (frustration) :( I apologize... atleast it was "gentle" sarcasm :)

As far as the problem: After a day of scratching my head I decided that the only cause for the glow plug light flickering during cranking and then staying on was the wiring of Terminal C. As stated above, it was connected to the light blue wire from terminal 3 of the old glow plug controller that has been connected the two black wires from terminal 5 and 6 of the old glow plug controller.

The solution: I clipped the wire and connected Terminal C directly to the new controller's glow plug feed post with a crimp on connector (I crimped and soldered the connection).

I am not using an inhibitor switch althought the 85 wiring diagram shows one. I am still reading up on whether or not I need the switch. It seems GM had done away with the switch but I'm not sure what type of a circuit they replaced it with if any. I spoke to several people who have dropped the inhibitor switch and none have reported any out of the ordinary issues.

So far everything is working great.http://www.dieselplace.com/forum/images/smilies/biggrin.gif The glow plugs cycled a couple times after I started the engine as normal.

So here's a review for those who want to do the upgrade or are trying to correct someone else's attempt:
The wires from the new 85-93 glow plug controller's harness should be connected as follows:
Terminal A is not used.
Terminal B connects to the “s” terminal on the starter. (Or any wire in the harness that receives power only when the engine is cranking.)
Terminal C connects directly glow plug feed stud. (I'm still trying to decide on the need for the inhibitor switch)
Terminal D connects to the main wiring harness and receives power when the ignition switch is in the ON position.
Terminal E is grounded to the chassis.Hope that helps!

[Subzilla]

Glad you were able to figure it out. There's some good info in the Member's section of the Page about glow systems: http://www.thedieselpage.com/members/guide13.htm

I'm pretty sure you can bypass the inhibit switch without any problems. I actually added an in-cab, cut-out switch so I can control when the system kicks in. My vehicles will start without GP's after sitting for 2 hours or less so I'll leave the system off. I feel this will prolongs the life of the system. Plus once the engine is running smoothly, I don't need those extra glow cycles.

Also, check the number on your glow plugs to make sure they aren't the "unwanted" AC9g's. These will swell if overglowed, so to speak. If they are the 11g's or 60g's (AC brand), you're good to go. There are other brands with different numbers, just make sure they aren't 9g's.

Again, these guys here on the Page are more than willing to help. Just look at the number of posts some of them have - it can be in the thousands - and that's not just asking questions about their own vehicle problems!

[ordiesel]

Thanks for the info. Took the beast camping this weekend for a shakedown run. Made nice list of "stuff" TODO. The GPs are next on my todo list, I want to swap in AC60g I have a feeling the current GPs are probably 9s.