Low Temperature non-cranking M35A2

[saddamsnightmare]

March 1st, 2009.

Low temperature non-cranking issues M35A2:

To the MAster Mechanics:

My 1971 Kaiser Jeep Deuce "Saddam's Nightmare" has suffered the annual reoccurance of the non-cranking issues in 22-24*F conditions. She will start at 30-35*F, but not at ten degrees colder. Last year this time it took the replacement of the starting batteries and the starter push button switch to solve these issues..... Now something else in the electrical system is not functioning under low temperature conditions enough to not permit her to crank.
The alarms work, the master switch arms, but when the starter is pushed... no crank, no click, no nothing. This truck is normally one of the fastest starting trucks in cold conditions above 30*F.... it beats any modern glow plug truck for starting quickness.... if it will crank! I should post this one off to Will Wagner... if he hasn't seen it or heard of it, no one has.

Sincerely,

Kyle F. McGrogan

 

[DaveP]

I think if it was mine i would take a look at the starter solenoid.

 

[WillWagner]

If you've done the button and batteries, a guess would be the solenoid. If the issue is present now, whip out the DVOM and track it down. I could be a wire that has multiple strands broken so when the amb. temp reaches the magic number, there is too much resistance in the wire and the amperage needed to make things work in the colder temps just isn't there. Goofy electrical issues can be frustrating, sometimes they get "fixed" unknowingly when you are trying to figure out what's wrong.

 

[badgmc56]

First off, make sure batterys are in good working order. The extreme cold will effect them even if they are fairly new. Load test them when the temp is in the problem range. Next, check all connections and make sure there are star washers behind each connection. You can have a buddy try to crank the truck while you check the connections for heat while cranking. A bad connection will build up heat. If all this is in order , then check to see if there is a pulse to the starter. If there is , you probably have a bad starter. I have seen this before in cold conditions. If no pulse. check solenoid and so forth working your way back to the starter switch.

 

[cranetruck]

Check your starter relay, it may have been a problem all along.
Metal shrinks a bit when it gets cold, so a questionable connection can open...

 

[dabtl]

You could move to Texas. It will be in the 70's later this week. I have never had a cold starting problem, well other than not wanting to go outside and start the deuce.

 

[OPCOM]

I think if it was mine i would take a look at the starter solenoid.

and the relay that controls it. The big one mounted on the engine. Maybe it has got some oil/grease/dirt in it and won't move when it is so cold.

 

[Jake0147]

You hear absolutely nothing? Then I'd tend to agree with the above posts, look into the starter relay and/or the button. You CAN hear the starter relay "click" when it's working. Not as loud or heavy as a dead starter's "clunk", but it's very definately audible. If that doesn't "click", you can't expect anything beyond it to work. The button needs power in and power out when applied, the relay needs the two "little" wires to provide power and ground to get the "click". Get that working before you worry about the two larger wires at the relay and the starter it's self.

 

[saddamsnightmare]

March 1st, 2009.

I DO LIVE IN TEXAS! The starter solenoid would make sense, because I replaced every other component within the last year except for the starter solenoid and the relay on the starter. This truck has probably been run more on the road on long trips this last year and two months then it ever did in the last 19 years in the Army. The fuel pump kicks in, the button was replaced last year with a new NOS from Saturn due to the buttons contacts being worn, but the relay and the solenoid have not been addressed. I'll have to jumper the solenoid as I do not have a second body to handle any under hood work. The relay on the starter is probably too close to the exhaust pipe when run hard for hours on end, It may have some heat related issues. Amazing how these trucks will run 99% of the time, but its the little things that trip them up.

The ordnance batteries were the hard part, as Uncle wouldn't let Exide sell me a new set.

I'll peck at it Tuesday if I get time enough.

Thanks again,
Sincerely,

Kyle F. McGrogan

 

[dabtl]

It could be a bad ground. I have to credit Bjorn for my paranoia about defective grounds. I have pulled every ground I can find on my two deuces, cleaned and replaced the bolts and washers.

I think it may not be the cold. It may be the GROUND!

 

[Jake0147]

March 1st, 2009.

I'll have to jumper the solenoid as I do not have a second body to handle any under hood work.

A couple of home-made improvizations come to mind for this mission-
First, a twenty five foot roll of bonded speaker wire, making sure it has some sort of ID as to which wire is which. (Usually the cheap stuff has a copper wire and an aluminum wire, some are striped on one side, some are ribbed on one side.... Unroll it, if it isn't already there then make a small hole in the center of the spool, stick a foot of wire through the hole, and re-wrap it. Crimp-on alligator clamps from Radio Shack or similar for all four ends. Hitch the rolled ends to what you're working on, and roll the roll to where you're working from. You can apply (modest) power or grounds to things, run your test light, volt meter, etc from where you are.
Second, short of that, you can make up a one-shot tester with a couple short pieces of wire, two alligator clamps, a couple of female quick connect crimp ends, and a low amperage (five or less) blade fuse. It gets expensive for big diagnosis, but I find it's often easy to put together with what's on hand for single-shot voltage/no voltage readings. Clamp that across the two "little" wires at the starter relay- If the fuse pops, then power and ground were available at the time. If it doesn't pop, it wasn't.
This last one works well for as a "taddle tale" for chasing intermittant wiring, especially bad grounds, (which can be intermittant and/or temperature sensative).

 

[cranetruck]

Kyle, if you have problem with your start button, it's time to install a diode to suppress the voltage spike that develops each time you release it. The start relay coil produces a voltage transient, which is largely ignored in these circuits. The start button contacts arc and get burnt after frequent use.
I have installed a diode to protect the switch on my 8x8, which uses a 3-position type (more expensive).
The diode can be a 1N4004 or equivalent.

 

[saddamsnightmare]

Diode diverter

March 1st, 2009.

Thanks gentlemen for the input(s), I will fish around Tuesday when I'm off
and see what the problem is.... hope it's not the starter switch, as those little devils shouldn't have called it quits in a year.... but I would have never thought of a voltage spike or using a diode to divert it..... jorn must be a genius, cause the only electronic item on the truck's the famous TACOM switch.... properly grounded and behaving nicely. Unlike most deuces on here, this one gets run, and run a lot, probably about 6,000 miles from Jan 08 to Jan 09, a lot of which was on the road running, contrary to what deuces were originally designed for (though some Texas roads do resemble road of Fallujah, save for no IED's)(Some parts of Dallas??)! I'll peck at it, but I'll bet you when I get home she'll kick over as it's now about 55-60*F!
Enjoy what's left of the weekend!

Cheers,
Kyle F. McGrogan

NB: Even the 1963 Swiss Unimog as slow to start, but the MB M180 gas engine's been updated with and electronic ignition and civillian plugs, but she hates cold weather.... like the deuce though, when she starts she'll run all day.

 

[tm america]

check the starter relay jump it at the starter relay if it cranks check wiring to the relay if not check the batteries ,grounds, and possitive connections at the batteries andat the relay also check the main starter wire at the starter and load test the batterieswhen they are messing up iwould guess at either the relay or batteries 6tl batteries dont last very long if the arent cycled regularly - driven at least weekly mine only lasted a year and they woulnt start in cold weather i went with deep cycle batteries that can be used as regular one to autozone has em about $70each