Puzzling 1952 m38 won't Start

radtech · Post by **radtech** » Tue Sep 05, 2017 6:10 pm

If you dont have 24v to the coil it will not start even in gear pulling it.It sounds like your batteries are no good if they won't crank the engine,If you have 24v to the pos.terminal of the starter you can jumper between it and the center pin on the distributor with an insulated aligator clip then maybe it will start with a push or pull it in gear with the clutch in let off the clutch when it is moving.I have the hand crank on my M38 so if the battery is too low to turn the starter but still has 24 volts I can start it.

oilleaker1 · Post by **oilleaker1** » Fri Sep 08, 2017 5:25 pm

wesk wrote:A lot of what is called "Shotgun troubleshooting" usually will cost you more in the long run. The solicited replies head off in different troubleshooting directions. Best to get the manual out and go to the no start troubleshooting page and then use a note padand record the result of each step.

In order for us to provide constructive suggestions we need accurate info. Exactly which wiring you have, IE early vs late, w/wo circuit breakers.

Pictures really shorten the guessing list when you have troubles, Try to post at least these shots but you just need similar angles and a few showing your battery cable connections and routing and the wiring on the rear side of the dash panel:

Wes, using a shotgun increases the chance you'll hit the problem with less rounds!

joebuck · Post by **joebuck** » Thu Sep 14, 2017 1:05 pm

Headed back to my camp tomorrow with new attitude and some appreciated advice from this board..........Reviewing the present....
1. Turn ignition switch on.........no gauges work, nothing... Switch off , horn or lights dont work... the jeep has what appears no electrical pulse what so ever.
2. Both batteries charged fully
3. All electrical posts clean and tight.
4. Ground to frame clean and tight......Is there another ground to check?

Action steps
1. Check behind instrument cluster panel to identify if circuit breakers are there.

m3a1 · Post by **m3a1** » Fri Sep 15, 2017 5:36 pm

The commonality is that no power is getting from the batteries to anything, whether it be circuitry routed through the ignition switch or direct to the starter which should crank whether the ignition is on, or off.

So, back to basics. Load test those batteries. You say they're charged but you don't say how you know that. If the batteries are confirmed to be good, check that negative ground and if that's confirmed to be good and you still have nothing, you can surely count on the positive cable being bad.

4x4M38 · Post by **4x4M38** » Fri Sep 15, 2017 6:27 pm

If you have the original military battery terminals,
and the terminals that screw to them, and the cable
with the loop attached to all of that, every one of those
connections need to be disconnected and cleaned.

I've had an F150 in the driveway not start and it was
because the wire terminal at the battery was corroded.
The same can be true on the negative side.

Clean them all.

You can also be reading 12 volts on a battery and it have
a dead cell and not enough goodie to fire off the starter.

joebuck · Post by **joebuck** » Fri Sep 15, 2017 7:56 pm

1. I have the wiring with the two circuit breakers behind the dash on left side

4x4M38 · Post by **4x4M38** » Fri Sep 15, 2017 8:28 pm

Hi Joe!
I hope deer camp is cooler there than here!

Two options with breakers.

There is or is not a circuit breaker for the
instruments attached to the back of the gauge
panel. No need to remove anything to check.
If it's there you have two screws vertically
between the upper and lower gauges on the left
side of the gauge panel.

If no breaker those two screws are not there.

The other option is three breakers screwed to the left
side of the cowl battery box. Just look up under the dash
at the left side of the cowl battery box. They are either
there or not.

See Wes' photo pages for pictures of all of this.

Good luck!

joebuck · Post by **joebuck** » Fri Sep 15, 2017 8:49 pm

Thanks 4x4. I definitely have the circuit breAkers. With horizontal screws

4x4M38 · Post by **4x4M38** » Fri Sep 15, 2017 8:59 pm

That breaker is there only to protect the instruments.

Do you have the other three on the cowl battery box?

joebuck · Post by **joebuck** » Fri Sep 15, 2017 9:17 pm

Thanks Brian. I have seen the picture of 3 breAkers but still confused where they are located exactly

4x4M38 · Post by **4x4M38** » Fri Sep 15, 2017 9:49 pm

Ok.
You do have two batteries correct?

One under the hood, and one under the cowl, behind the dash.
There is a hinged cover on the cowl, in front of the windshield
when it is up. Under that cover is the second battery, in a
sheetmetal box, spotwelded to the edge of the cowl where the
hinged cover is.

That box extends down into the passenger compartment.

As you are sitting in the driver seat the left side of that box
will have three circuit breakers screwed to it. If you have them.

If you have your foot on the starter switch your foot is almost
touching the bottom breaker. The military actually recommended
moving that bottom breaker because it was being damaged by
soldiers kicking it.

Don't forget. You should be able to turn the engine over with no switches
turned on. It won't start without the switches on and power to the distributor
but it should turn over.

You can have 12 volts on each battery but unless they are well connected in
series you won't have 24 volts to the starter.

Check all of your primary wiring (big) and connectors including
the ground.

Take care,

Post by **wesk** » Fri Sep 15, 2017 11:32 pm

Normally there are three CB's in the inboard end of the cowl battery box. Occasionally I see one that had the old Army service bulletin complied with to re-locate the bottom one to the backside of the firewall to keep the large shoe sizes from breaking it when they use the starter pedal.

This would be a good point to stop and take a fresh breath and view of the power issue.

I hope you are taking voltage readings with a digital volt meter.

The starter being stone quiet during all of this makes me strongly suspect two possibilities.

1-As mentioned earlier the internals of the switch on top of the starter have burned out.

Early vs late

Early Items HH & V need to be inspected for burning.

Late Parts N, J, K & L can end up badly burned.

2-Battery cable have serious issues.

joebuck · Post by **joebuck** » Sat Sep 16, 2017 7:30 am

Thanks guys. There is no circuit breakers in the cowl box. I think! Here is a picture. I am going to buy 2 new batteries and let's rule that out. Cell coverage bad out here but will post picture of cowl box

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joebuck · Post by **joebuck** » Sat Sep 16, 2017 7:43 am

I think we have found it!!!! Wes last photo of battery post voltage req. revealed my positive post closet to ignition does NOT show 24 volts. All rest were perfect. Headed to town for battery

4x4M38 · Post by **4x4M38** » Sat Sep 16, 2017 9:05 am

Take both batteries and have them check them both.