Glowplug, resistor bypass...fun

[Onestar]

I got my m1009 back in November last year. Had to do a little work to get it to shift and run properly.

I had to pull 6 or so swollen glow plugs, decided I didn't want to have to do that again so I read a bunch of good info about the AC60gs. Bought them, put them in, also found out I had to swap the gp relay so I did with the one mentioned from Oreillys. Truck started and ran fine, I read a post from Doghead about a 12v resistor bypass. In my young and dumb brain I thought there is no reason to have to do that the truck runs fine. Well a week ago I had starting issues, the truck has power and turns over fine but the glow plugs aren't working.

I pulled out the multimeter and started checking around and the resistors are dropping the voltage like they are supposed to. The relay is working properly, I still am going to do the resistor bypass now but would a resistor work one time and not the next?

Can I do the bypass and swap in new plugs and if they work properly assume the resistors were the problem? The card under the dash still looks brand new and it did when I originally swapped the glow plugs as well.

Thanks, any help is appreciated greatly. I am still trying to figure out the whole electric side of vehicles.

 

[Hanns]

Honestly just replace the glowplug card with a momentary switch and be done with it. Much more simple, more reliable and makes it harder for someone to steal your vehicle. My M1009 has a simple push button on the dash, when it's warm I'll push it for about 5-10 seconds to warm the cylinders, on a cold, cold day it's about 20 seconds. Truck fires right up, no problem. I'm a big fan of simple and reliable. 25 year old electronic circuit boards aren't what I call reliable.

 

[epartsman]

If you want trouble free you will need to get the complete set up from CUCV Electric. Plugs, connectors, relay, temp sensor, and upgraded controller card. Do the 12V Bypass and it's done for a long time.

 

[epartsman]

Honestly just replace the glowplug card with a momentary switch and be done with it. Much more simple, more reliable and makes it harder for someone to steal your vehicle. My M1009 has a simple push button on the dash, when it's warm I'll push it for about 5-10 seconds to warm the cylinders, on a cold, cold day it's about 20 seconds. Truck fires right up, no problem. I'm a big fan of simple and reliable. 25 year old electronic circuit boards aren't what I call reliable.

Manual momentary switch is cheap and can cause swollen plugs if held too long. The controller card when it's cold cycles the GP's after the engine is started to make sure all cylinders are firing until proper engine temp is reached which is better for the longevity of your 6.2. The manual switch method does not. You get what you pay for.

 

[Onestar]

Thanks, I'm doing the 12v resistor bypass now. I'll let you guys know if it lasts. If not I'm afraid of what it might be.

 

[Matt65]

I have had trouble free service from the AC60Gs on the resistor bypass triggered by a very old stock card. My plugs were in very bad shape when I removed them. All but two tested bad, how they were hanging on to life I'll never know. They were certainly victim to the cascade failure of the resistor.

My advice keep the card, but know how to bypass it in a pinch should it fail. The resistor bypass is a must even though you will not have Glow ability while jumping with slave cable.

ALWAYs Be sure to disconnect both negative battery terminals when working on any of the electrical systems. Remove the front neg first, reinstall it last.

 

[M1008driver]

If you want trouble free you will need to get the complete set up from CUCV Electric. Plugs, connectors, relay, temp sensor, and upgraded controller card. Do the 12V Bypass and it's done for a long time.

Ditto

I have the 60g's and gp resistor bypass done. 60g's need to be grind down or replace the connectors as they are slightly bigger. I replaced mine with insulated connectors.

I to have a manual switch, but it is wired so the stock systems works. I only have it for emergencies and do not use the switch. I spliced into the light blue wire on the gp controller card plastic holder. No need to cut any wires that way or disable the gp system. The CUCV Electric gp controller card works great for me too and is worth buying. All their parts are tops.

Here is a pic. I have since replaced the 8 guage wire with a newer one than shown.

 

[Onestar]

So I went out and did some serious electrical check outs.

Both batteries isolated are 12v each
The rear battery is 24v
The junction on the firewall is reading 24v
The connection on top of the relay is reading 25.4v (when turned on it drops to 10.3v)
The connection on the bottom reads 0v when off (when turned on its 10.3-11.6v)
The four glow plugs on the right side of the motor and the three on the passenger side front start at
about 9v and climb slowly when the wait light goes out they are at 12v

My original problem is I swapped the plugs to AC60gs about 3-4 months ago. The truck started fine and ran perfect all winter, I heard the switch on and off, it started quickly every time. This is all on the stock 24v setup (as stated earlier I hadn't done the 12v resistor bypass). One week ago on a cool morning I went out to start the truck and had a long wait light when it went out I turned the key and the starter was turning but the truck didn't start it sputtered the warmer the truck got. Once it was warm it ran fine and when I shut it off and started it back up it started fine. I'm confused because all of my wiring seems to be checking out. A neighbor said it might be a fuel issue. I'm thinking do the 12v resistor bypass swap the plugs to all new plugs and see what happens, any opinions or better ideas?

 

[tbearatkin]

sounds like Glow plugs to me. Check them first before doing other things. And if they are bad think about doing away with the resistor. Even quite a few in the military were bypassed. I showed mine to a Seabee Mechanic and all he had to say was that is so old school and that they bypassed them.

 

[JSF01]

Have you tested the glow plugs them self? I only ask because I once spemt 2 or 3 weeks thinking I had a glowplug problem so I swaped glow plugs did the resister by pass ect..., When cold it would not want to start, but when warm it started just fine. The ptoblem turned out to be I had a slight air leak in the fuel line. It was not that the engine was warm or cold but how long it had sat. After about 4 hours enough air leaked in to the fuel system to cause it problems starting.

 

[Onestar]

I did have one that I tested out it was the drivers side closest to the firewall and I did apply 12v to it and it heated up properly. What I find weird is that I have been daily driving it in the morning to work and evening home and haven't had any issues or even noticed that it was acting funny until that one morning when it almost didn't start.

 

[tbearatkin]

Get yourself a multimeter that is the best way to check glowplugs. Not by applying 12volts to them and see if they heat up.

 

[rickf]

You only mention 7 glow plugs. What happened to #8?
Someone mentioned burning out the plugs with a manual switch, will not happen with the AC60's as long as you are not feeding them over 12 volts.

 

[Onestar]

I didn't pull the 8th because the person that was helping had to run, and I wanted to be connected to it from the moment the key was turned until the wait light went out.

 

[sdasdona]

having the same problem, new glow plugs rated to 24 V lasted 3 days???? now their toast. Can you point me in the right direction to bypass the 12V resistor/ Thanks Randy

 

[tbearatkin]

Try here


http://www.steelsoldiers.com/cucv/56682-what-why-did-smoke.html