Newbie glowplug wiring question

[mdeboard]

I have a M1009 with two wires burned through near the glow plugs. I figure if I'm going to rewire two then I might as well reqire them all. I'm a bit confused about the fusible link wires. Are the .8 GRN wires the fusible links that are soldered to the .8 ORN wires? From what I've read fusible link wire is supposed to be 4 gauges smaller than the wire they are soldered to. And since the .8 ORN wires appear to be the same size on the diagram, I am more than a little confused. Thanks in advance.

 

[Warthog]

By reading the first few pages of the Troubleshooting section of the Tech Manuals,you will find the explaination of how to read the wiring diagams, what the wire sizes are and what the wire types are.

Yes the green wires at the glow plugs are fusable link material. They are not really protecting the circuit in the normal sense and if you made them 4 times smaller that the orange wire, they would burn out very quickly.

Just use the 18 gauge fuseable link and you will be fine.

 

[mdeboard]

By reading the first few pages of the Troubleshooting section of the Tech Manuals,you will find the explaination of how to read the wiring diagams, what the wire sizes are and what the wire types are.

Yes the green wires at the glow plugs are fusable link material. They are not really protecting the circuit in the normal sense and if you made them 4 times smaller that the orange wire, they would burn out very quickly.

Just use the 18 gauge fuseable link and you will be fine.

Thanks for the quick response. I've looked through the tech manuals. This is going to be a steep learning curve for me.

 

[Warthog]

I'm not a GM engineer, but I would think they used the fusable link of the glowplug wires to protect them from the heat of the exhaust manifolds. This is total speculation on my part.

One thing most people miss is the first few pages on the troubleshooting section, Alot of good info there.

Oh yes, welcome to the site.

 

[mdeboard]

I'm not a GM engineer, but I would think they used the fusable link of the glowplug wires to protect them from the heat of the exhaust manifolds. This is total speculation on my part.

One thing most people miss is the first few pages on the troubleshooting section, Alot of good info there.

Oh yes, welcome to the site.

Thanks!

I was thinking along the same lines. I have some 18 gauge PTFE wire with a high temp rating but wasn't sure if I should use it. I'm having a hard time finding fusible link wire.

Something had to fry those wires. I'm guessing the resister is bad and the card most likely won't be in good shape. No biggie. I had planned on doing the manual switch and resister bypass anyways.

I've already done the doghead mod and replaced the glow plug relay with the ST85.

 

[mdeboard]

I pulled the glowplug card and resister today. The card had two visible burn spots on it and the wire on the right side of the resister was partially burnt through.

So I've removed and bypassed the resistor. I cut the undamaged wire on the left and am using that to power the GPR from the 12v junction right terminal to the up and left of the GPR.

When I get more time, I'll wire in the manual glow plug switch and test each of the glow plug wires and the GPR.

Does anyone see anything wrong with what I'm doing so far?

 

[wired1000]

Question I haven't seen answered... kind of related to this thread. What is a suitable amperage rating for a manual glow plug switch? I'm planning to install one as a PM in case my card goes out at an inopportune time. I know it should be a momentary switch to prevent operator error. Thanks in advance!

 

[mdeboard]

Question I haven't seen answered... kind of related to this thread. What is a suitable amperage rating for a manual glow plug switch? I'm planning to install one as a PM in case my card goes out at an inopportune time. I know it should be a momentary switch to prevent operator error. Thanks in advance!

I used a 20amp switch. I haven't had any trouble so far.

 

[Warthog]

You can install a one wire manual switch from a ground source, to the switch and then to the blue wire on the Glow Plug relay, you are just providing a ground path and it will just draw a few amps.