M35a3 without batteries...

[texasjake]

I have a A3 without batteries, so I jumped started the truck with no problem.
Where I disconnected the jumper cables the truck quit running. I was thinking the A3 would run without batteries. What am I missing?

 

[Truckoholic]

Being that it is a CAT engine, a lot of the CAT motors have a solenoid on the injector pump, that even though the engine itself will run fine with no power, that solenoid requires power to keep the injector pump going. So when power is lost, the solenoid disengages.

I don't know for sure as I am not familiar with the 3116 engine. I just know that's the way it is on a 3406B. If you can take the solenoid off, and wire it in the fuel on position, and put it back in, it would run forever with no batteries. But then you would not be able to turn it off without removing the solenoid from the injector pump.

 

[Truckoholic]

The Cat 3116 diesel engine comes with a electric fuel shutdown solenoid which is controlled by the key switch. It is located on the Governor/pump assembly [threaded in] with two wires controlling the electro-magnetic on/off function. The solenoid is energized at all times when the engine is running which means it can get hot and sometimes fail.

Found this on a website. So, looks like I was right. Even if you just had a small battery hooked up to the solenoid, you could run that thing all you wanted to. Or like I said, if you could figure out how to take the shutdown solenoid out, and wire it in the "On" position, it would be fine that way too.

 

[ODw/envy]

Good to see ya Jake.

I would have thought the same thing. I have done that with a diesel and many gas engines in the past. I have been cranking my rock crawler that way for 2 years (too cheap to by a battery I guess). Thanks for posting.

OD

 

[ODw/envy]

Jump the terminal from the gen to the solenoid terminal maybe? A piece of wire with ends and wing nuts? Sounds sketchy. I suppose it would depend on how bad I needed to move it.

If you'll buy the fuel I'll bring Albert's tow-bar and move it around for you.

I would not mind another West Texas run.

OD

 

[wreckerman893]

I can slave off my M35A2's without batteries but rumor control has it that running one very long without batteries will kill an alternator. Don't know if that is true of the A3's as well.

 

[73m819]

I can slave off my M35A2's without batteries but rumor control has it that running one very long without batteries will kill an alternator. Don't know if that is true of the A3's as well.

Should not because it takes the batteries to EXITE the alt., the alt would just be spinning doing nothing

 

[Jake0147]

It would seem to me that two of the cheapest junk, used, core, mismatched, outdated, or otherwise useless (and inexpensive to free) batteries you could come up with should alleviate any issues here. That would not make up for the slave starting, yet it would give the alternator something to "work on" to keep the electrical system up and alive, and thereby able to operate the fuel solenoid as it should, even if it wouldn't restart on it's own afterwards.

 

[cranetruck]

I can slave off my M35A2's without batteries but rumor control has it that running one very long without batteries will kill an alternator. Don't know if that is true of the A3's as well.

Right, once the engine is started and the alternator charging (the batteries on the other vehicle is the load), you will create voltage spikes that will kill the alternator and possible other electronics on the A3 when removing the jumpers.
For trucks that don't need batteries to run, like the multifuelers, disconnect the alternator before slave starting.

 

[Heavysteven]

So in theory in an M35A2 Multifuel, if I was driving down the road and my batteries fell out it would keep running (assuming fuel has no issuses)

In an M35A3 batteries are a critical requirement it seems.

 

[ryker725]

You have an A3 which means you likely paid well over 3 grand for the truck. You do know that you can buy military replacement batts for $150 a piece new.. or Interstate remans for $60. Buy some new batteries.. Problem solved..

 

[Truckoholic]

So in theory in an M35A2 Multifuel, if I was driving down the road and my batteries fell out it would keep running (assuming fuel has no issuses)

In an M35A3 batteries are a critical requirement it seems.

That would be correct. Also one nice thing to keep in mind You know how they have those EMP's. ElectroMagneticPulse or EBombs that knock out electronics and cars ignitions supposedly? Well you don't have to worry about that with your M35A2 The rest of the neighborhood might be fried, but you'll be out cruisin' the town no problem.