How to swap out GP controller card thingy on firewall?

[AJMBLAZER]

Thanks to a guy over on CK5 I now know why Big Ugly is dead. Got the parts to fix that but we also discovered something's wrong with the GP controller card thingy on the firewall behind the air cleaner assembly. I'm getting 24v straight through it and to the "in" side of the relay.

Looks sorta hard to get at. How do you remove that thing?

 

[JohnFire]

remove the cover screws and then it is 3 bolts, the rest is just removing the wires. It is a resistor block. The bolts sometimes need some lube. If not you will strip out the nut rivets.

 

[AJMBLAZER]

Cover screws? Mine appears to be fixed to the firewall somehow...




Lemme go look at it again.

 

[AJMBLAZER]

Ah HA!

Alfa Heaven strikes again. Morons. Taking a fingernail to what looked like welded on bolt heads on the top and two on the bottom revealed a heavy layer of black CARC paint right over 20 years of grime. Yep...I'm not surprised somehow.

Found those cover screws. Bottom two look like they'll be fun to get at.

 

[CCATLETT1984]

oh jeeze, its a RESISTOR, not a thingy. there are three bolts that hold the shield to the firewall, the resistor is bolted to the shield. They arent hard to get at, not at all. Just use a swivel extension or socket. piece of cake.

 

[AJMBLAZER]

Eh, thingy is my be-all, do-all, end-all expression since I finally *mostly* got the word f^&ker out of my common vocabulary after the Marines.

 

[CCATLETT1984]

LOL, I may still have a spare resistor in the garage. I'll look tomorrow

 

[ida34]

I am pretty sure you will see 24 volt until there is a load then it will drop to around 12 volts. If I am correct you need to check it under a load to be sure. This is why the glow plugs all go bad at the same time. When one glow plug goes the current draw drops and the plugs that are left see higher voltage. This continues like a snow ball with each dead plug adding more voltage to kill the other ones. I had a connector come off and before I knew it I had three glow plugs go bad. I replaced them and replaced the connector on the loose one and everything was good.

 

[AJMBLAZER]

Hrm...have to check that. Guy who helped me trace down the fried fusible link (thanks to the Minnesota NG for the cheeseball fix by the way) says it shouldn't be 24v at all, only 12v.
Time to consult the -20.

 

[ida34]

The resistor will only drop the voltage when it sees a load and it must see the exact right load to get the voltage right. I don't know why but it seemed like the -20 did not cover this at all when I was checking my system. I think the trouble shooting is in Chapter 2. Look for the electrical trouble shooting section and it has some step by step directions. Basically when your glow plug relay kicks for a fraction of a second you will get 24 volt then it will rapidly come down to 12 volts. You volt meter does not provide enough of a load to trip it.

 

[AJMBLAZER]

Reaaaallllly? Hrm...how would I go about checking it's "goodness" then?

 

[Crash_AF]

Hook the voltmeter to it and then energize the GPR... if it works, then the voltage will quickly drop to 12V range if all are working right... higher than 12V if you have plugs burned out.

Later,
Joe

 

[AJMBLAZER]

Excuse the nooboscity but how do I "energize the GPR" ?

 

[doghead]

Re: RE: How to swap out GP controller card thingy on firewal

Excuse the nooboscity but how do I "energize the GPR" ?

Call Scotty on your communicator, and say "Energize the GPR, Scotty!"

 

[ida34]

RE: Re: RE: How to swap out GP controller card thingy on fir

If I remember right you ground the terminal with the small blue wire. You should check your glow plugs first. The quick and dirty way is to connect a test light to the positive on the front battery then touch the tip of the light to the blade connector on each glow plug. If the test light does not light up then that glow plug is bad. When all the plugs are know to be good them ground the blue wire and watch the voltage at the glow plug relay. If should start out at 24 volts then come down to the 12 volt range pretty fast.

 

[AJMBLAZER]

RE: Re: RE: How to swap out GP controller card thingy on fir

Terminal with the blue wire...at the junction on the firewall near the GP relay or one of the wires off of the controller card?

Plugs are Wellman 070's I put in this spring and literally don't have ten cycles on them.

 

[doghead]

RE: Re: RE: How to swap out GP controller card thingy on fir

To manually energize the glow plugs... There is a solenoid/relay on the firewall between the resistors and the master-cylinder. You need to ground the blue wire on it to activate the GP power. This blue wire comes from the controller card. Just use a jumper wire and go from ground to the solenoid on the blue wire terminal.

 

[AJMBLAZER]

RE: Re: RE: How to swap out GP controller card thingy on fir

http://www.steelsoldiers.com/modules/PNphpBB2/files/dscn1496_185.jpg

What and where?

 

[doghead]

RE: Re: RE: How to swap out GP controller card thingy on fir

here

 

[AJMBLAZER]

RE: Re: RE: How to swap out GP controller card thingy on fir

Okay, gotcha. Thanks.