m35a2 has no power to anything electrical

[63E10H8]

i tried to start my 1970 m35a2 buzzer came on, started cranking then all of a sudden nothing. Batteries are new and have a full charge, up until today everything worked perfect. any help would be appreciated.

thanks,


Rob

 

[Wildchild467]

Clean the battery posts and make sure your cables have a good connection. Sometimes if there is a bad connection, they connection will arc and create an open circuit. Check ALL the battery connections and the connections on the starter and starter relay with a wench to see if they are tight. You would be supprised how things can loosen up.

 

[63E10H8]

thanks tom, Ill give it a try.

 

[Warthog]

You might even load test you batteries. I have seen some on the shelf that where bad.

I bet it is your cables.

 

[RedbeardTheZombieHunter]

My deuce had the same problem before I go it. The previous owner just jumped the starter solonoid to get it running, but since my recovery trip was an overnight run, I needed lights so I ran a .014 gauge wire from the main power switch on the hot side, to the hot lead on the batteries. Flipped the switch and the low air buzzer started buzzing. I haven't found the issue yet, but sooner or later I'll get to crawl through and find the problem. I also had to run a lead from the hot side of the starter button to the lift pump so I wouldn't have to crank it too long to get it started. Once I got her home, I installed a hidden "security" switch so the main power switch is dead untill the hidden switch is thrown. I still have the original steering wheel chain welded to the driver seat frame with a padlock to the wheel, but a little extra security never hurts.

Good luck chasing out your deuce gremlins! Keep us posted what you find as I might have the same issue with mine.
opcorn:

 

[Boatcarpenter]

Check the main ground.
May not have been cleaned and tightened since 1970.
BC

 

[kbd39452]

RedBeard did you ever figure out what your wiring problem was? I believe I have the same thing going on

 

[steelandcanvas]

RedBeard did you ever figure out what your wiring problem was? I believe I have the same thing going on

You have the same thing going on? Perform the same suggestions given to him. Let us know what you find.

 

[kbd39452]

I have cleaned all the terminals on the batteries, the grounds, and at the starter. I know I have a good solid connection and a little over 24V. Batteries are less than a year old. I'm just not getting power to my accessory switch. I think if I put a jumper wire like redbeard did it would work but I'd like to find the real problem.

 

[ralph3162]

Could just be a bad power switch.

 

[loosescrews]

I had a similar problem, turned out to be a bad connection at the master power switch. you can get to it from under the dash, but its very easy to just pull the 3 way light switch and access it through the hole.

 

[steelandcanvas]

Trace you power path with this schematic. Start at your batteries and work through all connections, don't jump around testing things, be methodical.

View attachment WIRING_SCHEMATIC.pdf

 

[AZK9]

Check the main ground. ...

When I experienced a similar problem... the main ground was indeed the reason!

The area around the connection was encrusted with dirt. I cleaned everything,
applied dielectric grease as needed and tightened things up. No problems since.

 

[Rmtaunton]

Also check the number 10 wire !

 

[BellinisCustom]

I know this is an old thread but need some help. We start our m35a2 daily, and when we backed it into the shop the other night it started right up, when we went to start it in the morning.. nothing... the accesorry switch wont turn anything on. start button wont turn it over. i took the switch off and it has 11.1 volts to 3 of the 4 plugs. and 3.4volts to the last one..

 

[rustystud]

I know this is an old thread but need some help. We start our m35a2 daily, and when we backed it into the shop the other night it started right up, when we went to start it in the morning.. nothing... the accesorry switch wont turn anything on. start button wont turn it over. i took the switch off and it has 11.1 volts to 3 of the 4 plugs. and 3.4volts to the last one..

I'd start at the batteries and then the main solenoid on the engine block. Make sure all the connections are tight.

 

[BEASTMASTER]

I had that problem a while back. came back from a ride, and two days later ,nothing. started checking everything with the volt meter. both batt. had 11.8 volts. was going crazy. took the batts. to auto zone and had them load test them. the 17 year old batt. had a dead cell, and another wasn't to healthy. the 3 year old batt was healthy. replaced the 17 yr. old with a walmart special and it's been fine ever since.

 

[rustystud]

I had that problem a while back. came back from a ride, and two days later ,nothing. started checking everything with the volt meter. both batt. had 11.8 volts. was going crazy. took the batts. to auto zone and had them load test them. the 17 year old batt. had a dead cell, and another wasn't to healthy. the 3 year old batt was healthy. replaced the 17 yr. old with a walmart special and it's been fine ever since.

You really should never mix batteries like that. The older battery will shorten the life of the newer battery. Since you need two batteries at least, or four if their smaller ones. Buy them all at the same time. You will save money in the long run and your truck will love you more !