Simple Manual Glow Plug Switch Question

[DanR7985]

As the title says this is a simple question. I am going to do the manual glow plug switch on my 1985 M1009. It looks very very simple. I have two simple questions though.

1: What gauge wire should I splice in the blue wire with and what gauge to run the ground? I am electrically challenged and have no clue. I searched high and low, but I could not for the life of me find an answer.

2: Would I be safe to assume that I should put an inline 20amp fuse between the splice and the manual switch itself?

3: Is there a certain amp rated switch that I have to have? For example do I have to have a 20 amp or do I need 30amp etc?

These might be on an electric diagram, but I can't read them. I've tried over and over and I have no clue what any of it means.

I appreciate greatly the answers. I was going to go dove hunting Saturday, but I couldn't get my blazer started when it ran and started fine the day before. It has new batteries and glow plugs. After trouble shooting I am 90% sure it's the controller card.

 

[doghead]

14 ga wire and no fuse. It is fused on the positive side. A manual pushbutton on the light blue wire is simply grounding the relay coil to activate it. I'd use a 20 amp rated pushbutton.

 

[Hasdrubal]

I was told to use a 30 amp push button when I did mine 8 years ago. Maybe its overkill.

 

[1stSarge]

These might be on an electric diagram, but I can't read them. I've tried over and over and I have no clue what any of it means..

After trouble shooting I am 90% sure it's the controller card.

What did you do to troubleshoot it?

Wouldn’t you rather fix the problem that might easily be a bad connection, rather than hack the wiring? The level of support on this forum is outstanding for such endeavors.

The typical glow plug relay normally draws less than 2 amps, and is already fused with the 20 amp Engine Control Fuse (#17 on the fuse block diagram). The original wire is 18 gauge SXL.