M931A1 w/ Cummins NHC-250 won't start

[tobyS]

I was worried about having a problem on the road so went with 2 new 1400 cca 8D. First picture is the 923 and second is my 817, which both got new sets at much less than one Hawker cost. Bus battery is good.


But I can't imagine them sitting 18 months then expecting reliable operation.

 

[Csm Davis]

KaiserM109 few things if you want to jump the truck in the backwoods most heavy equipment is 24v second if you want your batteries to live long and not have to crank it every few weeks get a solar panel of some kind I would recommend the solargizer brand, but you need the big one not the small ones.
Third a auto water setup will help keep them alive also.
Fourth they make 24v jump boxes or you can use 2 or more 12v boxes.

 

[KaiserM109]

It'a New Years night; my truck is sitting in a Walmart lot in Hayes Kansas and my wife, the chase car driver, and I are holed up in a Motel 6 waiting for the storm to blow over.

It took longer to get the trailer ready for the road than I expected, so we only got to the north end of Ft. Worth before dark overtook us on Sunday and we took a motel room. The next morning the batteries were dead because I thought that when you turned the BATTERY SWITCH off the BLOWER went off too; but nay not so. We were too far from anywhere to plug in my new 40 amp charger, so the only thing to do was go off the grid. We bought a small 700 watt generator.

It took about 1hr. and 15 minutes for the charging current to drop from 40 amps to below 10. The charger is designed to shut off when the battery is charged, but I believe it determines that by when the charging current drops below a certain level, probably 2 amps. With 4 batteries in parallel, it never drops below about 6. Leaving it on longer than that will probably overcharge it.

I’m supposed to be a work tomorrow, but not gonna happen. We expect good driving weather tomorrow, so maybe next day.

 

[tobyS]

Hope she starts in the morning.

I'm kinda curious how you used a 700 watt generator to make 40+ amps @24 volt. By my math with no efficiency loss, 40 x 24 = 960. That is about 1/3 more than a 100% duty. Did your generator handle that OK?

I would imagine about now you see why I think $400 at O'Reilly is a good investment.

 

[Suprman]

I believe his charger is 12v and he temporarily reconfigures his batteries to charge.

 

[Tow4]

If you have a set of REAL (large AWG wire) jumper cables that are long enough to reach from your chase car to the battery box in the truck (or take the batteries out), you can charge each battery in the truck one at a time, with your chase vehicle for an hour (one hour for each battery), then start the truck and be on your way. Depending on the chase vehicle, it will have at least a 80 amp alternator. That will charge each battery enough in an hour, may be less, to get the truck started. Run the charging vehicle at 1000~1200 RPM to get more cooling air thru the alternator.

Good luck.

 

[KaiserM109]

Well, I'm home and the truck is too, almost. I think it probably believes that it belongs to Walmart because it has spent the last three nights in one Walmart parking lot or another. I live south-east of Denver and the truck's new home will be north. There is a Walmart halfway in between right off of I-70 and we parked it there to go to dinner. We decided to leave it there over night instead of driving it south, then north again today. We got up and there is 2" of white stuff and there are a couple of roads between the truck and its new home that I don't want to drive it on, so it will probably spend another day in the care of Sam Walton's enterprise.

RE battery charging, auto batteries are normally charged at 14.7 volts and they take whatever current they will take according to their charge level and condition, up to their limit, usually 8 amps. A fast charger puts out 15.3 volts and the battery will take more current, but can be damaged. My new super charger puts out 15.3 volts and up to 40 amps. By arranging them in parallel, and as long the batteries are balanced and in similar condition, the current will be split evenly, 10 amps per battery. My original charger, probably purchased at Checker Auto, will put out up to 8 amps at 14.7 volts and will probably make a decent trickle charger, but not a quick charger for 4 batteries.

In Ft. Worth the batteries died because I assumed that shutting off the BATTERY switch also shut off the BLOWER. We were too far to reach "The Grid", so I purchased a 700 watt generator. So, 40 amps times 12 volts is 480 watts. Assuming the charger has an efficiency of 80%, It needs 600 watts. Because of another "forgot to ..." I killed the batteries in Hayes, KS and my "off the Grid" system saved me. The next day I killed it again trying to start it and it rescued me again. On the next attempt I used starting fluid because the ether canister seems to be non-functional. I was amazed at how fast it started.

More later.

 

[FMJ]

Glad you made it Arlyn. Oreilly sells 24 volt chargers, and 6TL batteries.

Ed

 

[KaiserM109]

...Oreilly sells 24 volt chargers ...

Ed

That would be preferable to having to reconfigure each time. I will definitely look into it.

 

[FMJ]

Do you still have your 109?

I ran into you in Norman OK a few years ago didn't I?

 

[KaiserM109]

Do you still have your 109?

I ran into you in Norman OK a few years ago didn't I?

You might have; are you the guy who gave me the tire tool? If yes, thanks. It is about to come in handy. The 109 was for Bushmaster5000 and yes, he still has it, though it has problems. I do have my own, and it is non-turbo and sick.

I believe you came in a CUCV which you towed home behind a deuce, which later blew a seal; right?

 

[FMJ]

Correct!

 

[KaiserM109]

I learned several things on this 2500 mile, 13 month saga:

• TM manuals on a flash drive can be a life saver.
• Read the TMs about how to operate the vehicle before you arrive at GL.
• There are five switches on the dash of an M923 that can kill the battery if you don’t turn ALL of them off.
• If you have a noise that starts at around 40 MPH that sounds like something is grinding the end of the transmission off, check the bolt that tightens up the spare tire.
• You can’t mix radial and biased ply tires, even if the government put radials on the ground and a biased ply NTD in the spare rack. Apparently my truck was upgraded and they put Michelin XLs on the ground, but neglected to upgrade the spare.

• An NHC 250 is hard to start when it is below 20 degrees, and taking the air cleaner off to use starting fluid is complicated. I am thinking about drilling a hole in the pipe between the air cleaner and the engine, welding a nut over it and plugging it with a bolt w/lock washer. I could remove the bolt, spray fluid through the hole and start it.
• An M923A1 is Really Big!!

 

[tobyS]

A diesel mechanic friend suggested doing something similar. He has seen a couple that the valves malfunctioned (dumping lots of ether in) and did damage to the engine... so recommends the entirely manual method (like your bolt hole). I'll be doing that also when I install a block heater.

Re the tire. On my Suburban, I used my spare and even though it was never on the ground, must have let some water into the steel belts, rusting them. When it let go, it looked a lot like yours. I notice your tire is a Michelin and that there is orange near the steel chords. This may not be a problem of mixing bias and radial, but having radials that have gotten water into their steel chords.

Is this an A1 or a basic? Most A1's have singles. I would not be surprised if someone changed the wheels and tires from an earlier model (809 series) if it is an A1. At least one M817 in a current sale is sporting the same 11.00 Michelins... making me wonder how old your tires may be.

 

[Csm Davis]

[*]An NHC 250 is hard to start when it is below 20 degrees, and taking the air cleaner off to use starting fluid is complicated. I am thinking about drilling a hole in the pipe between the air cleaner and the engine, welding a nut over it and plugging it with a bolt w/lock washer. I could remove the bolt, spray fluid through the hole and start it.

You guys are over thinking the whole starter fluid thing, 939s are easy! get truck ready to fire, get in roll the window down take the can in your left hand, reach out and squirt a shot in the mushroom as you turn the engine over, this is much easier to do and safer for your engine than putting in after the filter. If you can't reach it from the seat as some of us can't, just spray before you sit down it still works. And it also works with the tapered screen around the mushroom.

 

[juanprado]

• You can’t mix radial and biased ply tires, even if the government put radials on the ground and a biased ply NTD in the spare rack. Apparently my truck was upgraded and they put Michelin XLs on the ground, but neglected to upgrade the spare.

[/QUOTE]

The spare was probably "borrowed" before it was turned in bu the unit or while it sat at a lot(s) waiting to be processed. Some I trucks I previewed and many pics on Gl show missing items or mis matched tires.

 

[juanprado]

If the picture of the blowout is fresh after it happened, then TobyS is spot on. One of the biggest problems is cheap and quick fixes when tires are repaired instead of doing it correctly. The current best method is a patch/plug that seals the air on the inside (patch) and the plug seals the hole to keep water from wicking in between the cords and rusting out the belts. High heat ( operating the tire at Highway speeds) combined with weakened belts rusted by water and allowed to sit for who knows how long combined to create the perfect blow out. Air pressure is also vital in the equation.

I was a manger at a company owned western auto where we sold 200 plus tires a week. You would not believe some of the tires that came in blown out or needing repair and how poorly the average person treats their tires. Remember a tire is just a condom you are rolling around on.

Just be glad it was not in the front as the pucker factor would have been intense.

 

[ichudov]

You guys are over thinking the whole starter fluid thing, 939s are easy! get truck ready to fire, get in roll the window down take the can in your left hand, reach out and squirt a shot in the mushroom as you turn the engine over, this is much easier to do and safer for your engine than putting in after the filter. If you can't reach it from the seat as some of us can't, just spray before you sit down it still works. And it also works with the tapered screen around the mushroom.

This is what I do and it works great.

 

[juanprado]

The spaghetti tubing is usually the weak point in the ether system and easy to change out. 1/8 air line & ferrules at any truck parts.

 

[tobyS]

I put ether in that way also but use at least twice as much. That it would be handy and at ground level is a benefit.

Uh, I hate to be a bearer of bad news KaiserM109, but it is likely you have a complete set of unsafe tires that have rusted steel belts.

Consider yourself lucky that more chaos did not develop and find newer tires immediately...in my opinion.



Edited to ask.... is there is a way to tell if steel belts are rusted before a failure occurs?