pl1338
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Call GM and ask them why a 25+ year old link didn't operate properly.....
haha! I guess I asked for that.
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Steel Soldiers now has a few new forums, read more about it at: New Munitions Forums!
MY M1008 caught on FIRE!
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haha! I guess I asked for that.
Could be that the card failed in the ON position, which caused the GP relay to engage and overload the GPs and the resistor pack. To many unknowns to make a final call.
The GP controller card is next to the steering column. It is about the size of a cigarette pack. Sometimes it has a cover and most of the time the cover is long gone.
The GP controller card is next to the steering column. It is about the size of a cigarette pack. Sometimes it has a cover and most of the time the cover is long gone.
pl1338
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OK, thanks for that bit of info. I'm headed out now and will update upon my return!
pl1338
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Well, I went and cut the resistors out, connected the batteries and she started up on the third short try. I put fuel in it, and drove it home. The card under the dash was all there, even in a cover. I did have a low transmission fluid moment where she started to give way, but a short walk to the store half way home solved that. Now, I just need to figure out what to do for glow plugs. I don't need them in the summer, but cooler weather may present a problem... I'm still not sure what that resistor actually did as far as functioning, it didn't look like it was connected to any GP's. That little silver solenoid on the firewall with multiple wires connected to it, the resistors were connected to it. Anyhow, thanks for the help, and I'll search the site here for some answers to any questions I have along the way. I have a bathroom project to get started on so this will be on the back "burner" for now! pun intended.
The way the resistor was wire is this:
Power from the 24v Positive bus bar to the resistors.
Resistors to the GP relay
GP Relay to the GP wiring harness
GP wiring harness to the plugs
Why not just rewire the GPs, by passing the resistor?
http://www.steelsoldiers.com/showthread.php?63366-Glow-Plug-By-Pass-Help beginning at post #20
Power from the 24v Positive bus bar to the resistors.
Resistors to the GP relay
GP Relay to the GP wiring harness
GP wiring harness to the plugs
Why not just rewire the GPs, by passing the resistor?
http://www.steelsoldiers.com/showthread.php?63366-Glow-Plug-By-Pass-Help beginning at post #20
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pl1338
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Excellent advice Warthog! Thanks a million! That little thread there seems like an easy to follow and easy to do conversion. I'll get started on that soon. Looks like Rockauto.com has the plugs reasonable, and it also appears that they have the glow plug relay for the J coded trucks for 22 and some change. This looks like it is a go for me, and if I get the bathroom project knocked out, I can have it in before it gets too cold... Now to look at that tranny leak...
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I just going back to the OP's original first statement: "I got this thing a couple years a go, haven't really done much to it,".
pl1338
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I'm wondering why you are going back to that? I love the truck, it is tons of fun, and when I get time to fiddle with it, I do, I like to tinker. I have four kids and a single income so it is tough to find extra cash to dump into it.
pl1338
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OK, I did the GP bypass, works great! The glow plugs are working fine, I started it this morning and the GP light went off, and she started immediately. it was about 50 degrees. The voltage meter shows in the green when I drove it out Monday, the problem is now the tranny! I replaced the vacuum lines, except the small one near the transmission, I didn't see one under there, but will look again. Here's the problem, I was rolling down the road, I hear a small hissing up front, voltage drops, I figure a belt is gone. Then I lose the transmission? Pull off, shut er down, lift the hood, and sure enough the gen 2 belt is gone, no problem. I start it up, it drives but then it wont shift out of first. I parked it. I replaced the belts, and vacuum lines, and started to drive it home, shifting fine, other than a hard shifting into 2nd. I get about a mile or so and then it starts coasting again? So, with full fluid and vacuum lines looking good, I'm stumped. I have read a bunch of threads on transmission issues and will be checking the valve on the side of the tranny, the little gear in there and my vacuum pressure along with the vac regulator. But with the loss of the gears, could that just be a straight up rebuild?
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There are 2 major problems with the GP systems in these older CUCV's. The GP card malfunctions closing the contacts on the GP solenoid, or the GP solenoid load contacts wear out and fuse together causing the GP's to burn out. I have had this happen on 2 of my vehicles while driving and switched the system to a manual momentary contact push button with pilot light which replaces the GP card. I also replaced the solenoid with a heavy duty starter solenoid. One other component that could influence the GP card is the coolant temp sensor which may malfunction "telling" the GP card that the engine is not to operating temperature. I have had no truble in the units that I have retrofitted with the manual switch; it is important to disconnect the GP card if you make the switch otherwise it could still activate the solenoid if left connected.
I always watch my volt meter when depressing the GP manual switch, it is easy to see that the solenoid is working correctly when the resistors and GP's are loading the circuit. I mimic the timing of the original GP card by counting off the seconds that the card would normally control; longer for cold weather, shorter for warmer weather.
I do favor the 24v system because it keeps the truck original and I like having 24 volts available to jump start gen sets and other vehicles.
Hope this helps,
Tom
I always watch my volt meter when depressing the GP manual switch, it is easy to see that the solenoid is working correctly when the resistors and GP's are loading the circuit. I mimic the timing of the original GP card by counting off the seconds that the card would normally control; longer for cold weather, shorter for warmer weather.
I do favor the 24v system because it keeps the truck original and I like having 24 volts available to jump start gen sets and other vehicles.
Hope this helps,
Tom
pl1338
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Thanks for the info Tstone,
The more I thought about it, I was leaning toward the card burning up those resistors. That voltage was way down and the resistors were way hot. If I run a push button, I was thinking about doing that to prevent the card from malfunctioning again and causing more problems, or possibly a cut off switch for the card, so it couldn't send any signals anywhere after the truck is started. Basically just turning it off. I wouldn't know which of the wires to splice into for the cutoff switch, so I would have to figure that out. That would also make stealing it in winter impossible!
I like the glow plug light, and everything, but I use a manual glow plug switch on my tractor, so why not this truck. It appears that my card is leaving the GP's hot for a about 30 seconds after the truck is started, I can hear the solenoid operating, and the amp meter also dropping and staying down until the relay turns it off. I'm sure this is normal, making sure the cylinders are firing.
The more I thought about it, I was leaning toward the card burning up those resistors. That voltage was way down and the resistors were way hot. If I run a push button, I was thinking about doing that to prevent the card from malfunctioning again and causing more problems, or possibly a cut off switch for the card, so it couldn't send any signals anywhere after the truck is started. Basically just turning it off. I wouldn't know which of the wires to splice into for the cutoff switch, so I would have to figure that out. That would also make stealing it in winter impossible!
I like the glow plug light, and everything, but I use a manual glow plug switch on my tractor, so why not this truck. It appears that my card is leaving the GP's hot for a about 30 seconds after the truck is started, I can hear the solenoid operating, and the amp meter also dropping and staying down until the relay turns it off. I'm sure this is normal, making sure the cylinders are firing.