M35A3 - No Start - Lost Prime

[Warthog]

Okay, I am usually the one providing the answers but I'm stumped on this one. First M35A3 I have worked on.

I am working on a stock M35A3. I was told that the truck had been running and was driven on and off the transport. Parked for over a year.

The fuel tank was dry so I added 15 gal of fresh fuel. Followed the TM instruction on bleeding the system (crank, cool off, crank again). No cigar. Tried using some starter fluid. It would hiccup but not start.

So I started reading all the threads. Checked and cleaned the check valve on the tank (it moved freely when I removed it). Changed the fuel filter. Checked the fuel cutoff. Pressurized the fuel tank.

Check valve is item # 24 in the diagram



Still nothing. Cranks good and fast, just no start.

Today I will remove the inlet fuel hose at the transfer pump and clean the check valves.

Any ideas?

 

[gimpyrobb]

You sure 15gal is enough?

 

[wreckerman893]

I have zero experience with the Splaterpiller engine in those trucks but you might call your local CAT dealer and see if they can give you some insight.

 

[wheelspinner]

CAT does nothing, including advice for free!

 

[Warthog]

You sure 15gal is enough?

Good point. I will visually verify that the pickup tube is below the fuel line.

 

[Warthog]

What ever happened to M35A3.net? I was hoping to get all my answers there.

 

[Warthog]

Checked the fuel level. The pickup tube was a couple of inches below the fuel level.
Double checked the check valve at the tank.
Checked the shut-off switch on the dash. It is functioning correctly.
Checked for voltage at the fuel shut-off. A-Okay. The shut-off clicks with voltage applied.
Checked the functioning of the inlet check valve on the pump. Looked good.

Still no start.

I think I will attempt to provide fuel from a can, bypassing the fuel hoses. While I didn't see any wet spots on the hoses, it is possible there is a pinhole and the pump is sucking air.

 

[wheelspinner]

Have you cracked the line at the first filter to see if the pump is sending fuel?

 

[Warthog]

This is an A3. Totally different fuel system than the A2. There is no pump in the tank. and there is only one fuel filter.

 

[wheelspinner]

Gotcha. I knew it was an A3 just wasn't aware of that difference.

 

[Warthog]

The A3 uses a mechanical "transfer pump" on the engine to draw fuel from the tank, send it thru the filter and onto the injectors. The injectors are where the pressure is built up.

 

[ca1517]

Not sure about an A3, but on tractors with the 3116, there is a manual hand pump, so when you run out fuel, you can reprime the system. When all else fails from this, I have removed the air cleaner, soaked a rag in gas, and held it in the breather housing with someone else cranking it over. The ATAAC engines are hard to start after running out of fuel

 

[Carlo]

Is there a hand primer on the motor? I'm not familiar with the CAT motor but if it has a primer can't you verify fuel to the filter and then to the pump? Turning the motor over with one injector loosened?

 

[welldigger]

Pressurize the tank and crank it over with the gas pedal to the floor. A3's don't like their fuel systems being deprimed.

If puffs of smoke exit the exhaust while cranking that is a good sign. If not then you may have another issue.

 

[combat32]

What you doin workin on a an A3? You got a lifetime worth of work yet to do on your A2

 

[Hoefler]

Open peacock valve at bottom of fuel filter and pressurize tank until fuel runs out. Close valve and give it a try. This worked for me.
if fail, it could be the "rack" on top of engine. A cat mechanic buddy of mine told me that mis adjusted rack will cause hard or no starts.
pete

 

[FMJ]

Here is a thread from my friend.

http://www.steelsoldiers.com/showthread.php?71649-Nellis-M35A3-recovery-sorta

 

[Warthog]

No manual fuel primer on the M35A3 3116 engines. I wish there was.

FMJ, I remember reading that but totally forgot about it. The other details outweighed the solution. Thanks for reminding me.

I will see if it helps and document how to do it.

 

[Warthog]

Over the weekend I gathered some parts for my attempt at getting the truck running.

Today I assembled my contraption, hooked it up, set the throttle pedal and cranked the motor. After a couple of attempts she came to life. Runs perfect.

I will be documenting the solution after my Patent paperwork gets back.

Thanks FMJ....

 

[goodguyzy]

I ran my truck out of fuel, tried to start it for a few days but no go. I figured it would be a good time to change the fuel filter while its non op. When I pulled the filter the fuel smelled more like tarnish than diesel, truck would smoke while trying to start and hiccup but that's it. Im wondering if I need to flush the lines out. What was the final verdict on getting the truck to fire back up.