No Start, Engine Spins slowly

[sandcobra164]

I've got some questions to an electrical guru. My M1028 will not start as the engine turns over very slowly.

Known.
1. Both batteries are good to the best of my knowledge. Both show an open circuit voltage while connected to the truck of 12.7 volts. I hooked my "smart" charger to them and they both showed 95% upon hooking up and I let them go through a charge cycle seperately. Water level is fine in all cells and no sulfation or corrosion noticed on plates in the cells or terminals. Regular 6TL batteries within past few years.
2. Truck will slave start just fine when connected to the Deuce through the NATO Slave receptacle on both vehicles.
3. Truck will not jump start using a running vehicle connected to either battery. Curiously, if I have the jumping truck hooked to the rear battery, it will shut off once I attempt to start the CUCV. Does not happen when hooked to the front battery. Yes, I do know to hook positive to positive and negative to negative of only one battery at a time.
4. Both Gen lights come on and glowplugs go through their cycle normally whether hooked to a vehicle or using it's own battery power.
5. Truck no longer has the resistor pack for the glowplugs behind the air filter. The glow plug relay pulls 12 volt power from the firewall as per the instructions posted to eliminate the resistor and has been wired that way for about 2 years. It does still have the 24 volt starter and the original starter relay. I looked at the wiring under the dash and see no evidence of heat or melting wires. The relay still sounds off as normal.

At this point, I'm assuming a bad ground. I've thought of testing this by hooking a heavy jumper wire from the negative terminal of the front battery to the engine block to test. I'm hesitant to do so as I don't want to upset the 12 volt 24 volt setup on this truck. The starter is the only thing left on the truck that is 24 volt and it's ground to the block by being bolted to it so running a jumper to test shouldn't hurt anything. I'm asking for advice as this is my pristine all original M1028 with only 6,900 miles on it. I can't take any chances on my youngest son Briggs favorite truck. Same one that won MV of the Month last month. Up one day, down the next!!!

 

[MakersTeleMark]

If it will slave start, I'm guessing your batteries, while statically testing fine, are really not up to the task.

 

[goldneagle]

You need to load test your batteries. Load tester is cheap to get. I got mine through AMAZON.com.

 

[sandcobra164]

Agree with both of you. Upon having Soldier B attempt to start truck, I'm reading 25.14 volts key off, 24.12 volts key on glowplugs warming, basically nothing when start is attempted. Batteries just died after sitting a few weeks. I wish I would have gotten some Hawkers when someone had them at the rally a few years ago. Sad thing is, I even PM'd the seller and told him to put me down for a pair. Then I messed around and forgot to pay him and pick them up. Hindsight is never 20/20. If a mod wishes to delete this thread, no worries as I don't think there is a whole lot to contribute to a no start turning slowly issue. I should have done the further testing before posting. It is odd that the truck started fine a month ago but the brown 6TL batteries do have a reputation for dying somewhat instantly.

 

[MakersTeleMark]

The solargizer was one of the best additions to my1028.

 

[gimpyrobb]

You checked to make sure the starter bolts aren't broke and binding?

 

[goldneagle]

You checked to make sure the starter bolts aren't broke and binding?

He said he had no problem starting it with a JUMP.

 

[Barrman]

I agree batteries are 99% probably your problem.

However, a severly damaged starter motor from the under volt starting attempt could now be part of the problem too. I had a battery go bad, slow starting for 3 starts and then nothing unless I was hooked to a running slave cable vehicle.

I should have just turned it off and not attempted to start when I heard it go slow the first time. Instead, I kept it turning until it started. That cost me brushes, windings and bearings in a starter. With new batteries in, it wouldn't do much more than make noise and the starter would be very hot to the touch. Slave cable to a running M35 and it would start almost like normal.

Not trying to be negative. Just pointing out that you might have hurt your starter with the low battery. Hopefully, you didn't.

 

[Sephirothq]

I had the same thing happen to my 1009. It turned out to be a bad starter. It was drawing too much amperage that the batteries could not provide. Once I hooked to the slave and tried start it from a running truck it would start.

 

[doghead]

Charge then take your batteries to a store and have them load tested.

I suspect a bad battery or a bad connection on the battery cables.

 

[antennaclimber]

Check all the battery connections and the wires themselves may be suspect.

This thread may help find a bad connection.
http://www.steelsoldiers.com/showthread.php?72880-Battery-Wiring-Maintenance&highlight=battery