Couldn't get 5-ton started on the trailer.

WildernessJeep · Mar 27, 2020

The driver just showed up with the M936 from Milwaukee. Dude made it in 24 hours--impressive. Regardless, the truck won't start. GovPlanet's auction has video of the truck running. I put two fresh 6TM batteries in it, but still get the same click from the used group 31's I had on hand. I get a click from a box on the firewall, but no joy at the starter motor. The click stops if I put it in any gear other than neutral. I jumped the starter, and got a "whirr", but it didn't engage the flywheel. Is there some other switch or relay in the circuit?

The driveshafts are connected, but the air brakes are completely locked. We tried dragging the truck back off with a Ram 3500, but the 936 won by law of tonnage. Anyone have an idea how to start this truck? Need it running to build air pressure!

NDT · Mar 27, 2020

Grab an air line and charge the air system so the brakes will release. The driver should have an air hose. Charge through the front emergency glad hand. Pull off w pickup.

glcaines · Mar 27, 2020

NDT said:
Grab an air line and charge the air system so the brakes will release. The driver should have an air hose. Charge through the front emergency glad hand. Pull off w pickup.

Follow NDTs directions to get the truck off the trailer. More than likely you have an issue with the battery cables and/or grounding not making good contact.

M35A2-AZ · Mar 27, 2020

Also it should only start in Neutral.

WildernessJeep · Mar 27, 2020

UPDATE:: RECOVERED*

Update 3/27/2020 at 8:17 PM. It's off the trailer. We got it off by combining the ether spray into the intake and jumping the starter motor long enough to build air pressure to release the brakes. Then I went for a helluva ride off that trailer.

Still don't know why it won't turn over on it's own, or what's wrong with the fuel system. Anyone with any experience on this kind of truck, feel free to chime in.

simp5782 · Mar 27, 2020

If the starter didn't spin over then i

WildernessJeep said:
UPDATE:: RECOVERED*

Update 3/27/2020 at 8:17 PM. It's off the trailer. We got it off by combining the ether spray into the intake and jumping the starter motor long enough to build air pressure to release the brakes. Then I went for a helluva ride off that trailer.

Still don't know why it won't turn over on it's own, or what's wrong with the fuel system. Anyone with any experience on this kind of truck, feel free to chime in.

Suction line is probably dry rotted from the filter to the injection pump if there are no noticeable leaks.

Replace the fuel filter as needed

Solenoids in the control box are likely bad. If the gauges do not twitch when you turn the key on or the solenoid pops loudly while trying to start.

NDT · Mar 27, 2020

You ran it on either long enough to build air pressure? What’s that, 2 minutes?

162tcat · Mar 27, 2020

NDT said:
You ran it on either long enough to build air pressure? What’s that, 2 minutes?

Ouch. I would have just aired it up with a compressor or the air from the carriers rig. At least it’s an older 250. I don’t think the 8.3 would be as forgiving if ran on ether for that long.

Sent from my iPhone using Tapatalk

74M35A2 · Mar 27, 2020

WildernessJeep said:
UPDATE:: RECOVERED*

Update 3/27/2020 at 8:17 PM. It's off the trailer. We got it off by combining the ether spray into the intake and jumping the starter motor long enough to build air pressure to release the brakes. Then I went for a helluva ride off that trailer.

Still don't know why it won't turn over on it's own, or what's wrong with the fuel system. Anyone with any experience on this kind of truck, feel free to chime in.

That's a good looking ride! Congrats, I'm jealous. Always liked the way that exact truck looks from the angle you took the pic.

You did what you could to get the truck off the trailer. That guy did not want to be there all day not getting paid. It may need a starter or engine now, but at least it is off the trailer. I've ran a bunch of ether through my engine when I first got my truck as well, running out of fuel and such. Know better now, but my engine was fine after. The guys above are right, if the driver would have just plugged his trailer air brake hose into your truck it would have worked perfectly, he should have known that. Oh well, done now.

The click you hear is the starter solenoid clicking in the PCB box. You will likely need to either replace this solenoid or the starter itself. If you jumped the 2 large studs on the back of the starter solenoid, then that is why it just spun and did not engage, as this send power to the starter motor body but does not throw the pinion gear into the flywheel.

Check for power at the starter on its solenoid small wire connection. Should be +24V when the ignition switch held in the crank position, as compared to ground using a meter. If so, you'll likely need a starter. If not, you'll likely need a new PCB solenoid.

I sell modern gear reduction starters for a reasonable cost, but others such as the original are available elsewhere as well. You may just need to replace the solenoid on the starter as well.

Good luck, and congrats!

fasttruck · Mar 28, 2020

It must have been running when it was loaded as the carrier's trailer has no winch. How did they do that ?

98G · Mar 28, 2020

Did someone pull the engine shut off and not reset it under the hood?

WildernessJeep · Mar 28, 2020

fasttruck said:
It must have been running when it was loaded as the carrier's trailer has no winch. How did they do that ?

The driver couldn't rightly say because he only spoke Russian. I understand they used a tractor.

WildernessJeep · Mar 28, 2020

74M35A2 said:
That's a good looking ride! Congrats, I'm jealous. Always liked the way that exact truck looks from the angle you took the pic.

You did what you could to get the truck off the trailer. That guy did not want to be there all day not getting paid. It may need a starter or engine now, but at least it is off the trailer. I've ran a bunch of ether through my engine when I first got my truck as well, running out of fuel and such. Know better now, but my engine was fine after. The guys above are right, if the driver would have just plugged his trailer air brake hose into your truck it would have worked perfectly, he should have known that. Oh well, done now.

The click you hear is the starter solenoid clicking in the PCB box. You will likely need to either replace this solenoid or the starter itself. If you jumped the 2 large studs on the back of the starter solenoid, then that is why it just spun and did not engage, as this send power to the starter motor body but does not throw the pinion gear into the flywheel.

Check for power at the starter on its solenoid small wire connection. Should be +24V when the ignition switch held in the crank position, as compared to ground using a meter. If so, you'll likely need a starter. If not, you'll likely need a new PCB solenoid.

I sell modern gear reduction starters for a reasonable cost, but others such as the original are available elsewhere as well. You may just need to replace the solenoid on the starter as well.

Good luck, and congrats!

I think the starter solenoid and motor are good, because when I jump it with a screw driver it turns over just fine. There is something between the dash switch and the solenoid clicking, which is inside a box on the driver's side firewall. I assume this is the PCB, and will go start inspecting to disassemble. Are these solenoids in the PCB going to be something that I can get at NAPA, or will I need to do a search and order online?

Also, the primer gets fuel no problem, but it still won't run. Where is this dry rotted hose I'm looking for?

simp5782 · Mar 28, 2020

WildernessJeep said:
I think the starter solenoid and motor are good, because when I jump it with a screw driver it turns over just fine. There is something between the dash switch and the solenoid clicking, which is inside a box on the driver's side firewall. I assume this is the PCB, and will go start inspecting to disassemble. Are these solenoids in the PCB going to be something that I can get at NAPA, or will I need to do a search and order online?

Also, the primer gets fuel no problem, but it still won't run. Where is this dry rotted hose I'm looking for?

They are 30$ online and $100 at napa or buy a rebuilt the control box. There is a thread on all of it.

There is a parts spreadsheet that has nearly every truck component and its civilian part number

Plenty of threads on no start NHC250s and their symptoms. Check and make sure it has fuel in it first. Then that the shut off valve isn't stuck rearward before you go chasing problems

WildernessJeep · Mar 28, 2020

simp5782 said:
They are 30$ online and $100 at napa or buy a rebuilt the control box. There is a thread on all of it.

There is a parts spreadsheet that has nearly every truck component and its civilian part number

Plenty of threads on no start NHC250s and their symptoms. Check and make sure it has fuel in it first. Then that the shut off valve isn't stuck rearward before you go chasing problems

Where is the fuel shutoff? I've actually seen several. There is one right on the side of the engine, next to the primer. Izzat the one you are talking about?

WildernessJeep · Mar 28, 2020

98G said:
Did someone pull the engine shut off and not reset it under the hood?

Where is the engine shut off? I see the one on the dash, and it looks connected.

M35A2-AZ · Mar 28, 2020

Here is a thread on bypassing the PCB (Box box). Will help to see if the pcb is bad.

Ever see inside the Protective Control Box?

I had a failure of the PCB in my M925A1 last year. As part of the troubleshooting, I made some notes and took some pictures, attached. Mine was the type with a circuitboard. Hopefully the wiring diagrams will be helpful to someone in troubleshooting. I also put together a little...

www.steelsoldiers.com

M35A2-AZ · Mar 28, 2020

WildernessJeep said:
Where is the engine shut off? I see the one on the dash, and it looks connected.

The shut off needs to be going forward on the IP pump. See pic. It is on the drive side of the motor.

Monkeyboyarmy · Mar 28, 2020

If that manual lever is forward like they described above, try screwing in the thumbscrew on the electric fuel shut-off solenoid. They engine will run without electrical power that way.

WildernessJeep · Mar 28, 2020

M35A2-AZ said:
Here is a thread on bypassing the PCB (Box box). Will help to see if the pcb is bad.

Ever see inside the Protective Control Box?

I had a failure of the PCB in my M925A1 last year. As part of the troubleshooting, I made some notes and took some pictures, attached. Mine was the type with a circuitboard. Hopefully the wiring diagrams will be helpful to someone in troubleshooting. I also put together a little...

www.steelsoldiers.com

Good stuff. Gonna go disassemble the control box, and see if I can find the culprit.

Couldn't get 5-ton started on the trailer.

Active member

Well-known member

Well-known member

Well-known member

Active member

Feo, Fuerte y Formal

Well-known member

Active member

Well-known member

Well-known member

Former SSG

Active member

Active member

Feo, Fuerte y Formal

Active member

Active member

Well-known member

Well-known member

Well-known member

Active member