John Deere 310-D Backhoe

[Delmer]

That's good, it means the pump isn't locked up completely.

I'd replace the fuel filters if you don't know when they were replaced last. Take apart any fitting between the tank and the transfer pump to check for garbage. Or blow back to the tank from the transfer pump. Do whatever it takes to get the fuel flowing better. Then loosen a couple of injector lines at the injector, carefully to not bend the injector, use two wrenches. Then hook the supply back to the injection pump and crank for ten seconds at a time, with five minutes rest, until you get fuel out the injector lines with no bubbles, then tighten them and it should start.

 

[thepumpguysc]

I still confused.. u put the fitting back in the inlet & checked the fuel level.?? its a 90* fitting..u couldnt fill it w/o it coming out..
As long as u have a helper..Take the INLET LINE back off..{the one in the back, not the return on top} put your thumb/finger over the inlet fitting HOLE.. crank the engine.. it should suck your finger/thumb..

 

[Dodgewade]

With the pump in a horizontal position, filling with fuel is almost impossible and a mirror must be used top see in it. I did put the 90° fitting back in and poured about add much on everything as I did in it. I did that for a number of times and when cranking the fuel you could see disappeared.
I may get a chance to mess with it this week and I will try taking the inlet line loose to see if it has any suction to it.
Was you able to see the picture? The supply line comes top the pump at and angle an the 90° fitting/adapter is connecting the two together.
Maybe I'm missing something with filling this up and watching or looking after cranking it over a spell.
Thanks.

 

[Deon]

I am following this with great interest as I have a same machine. I am also confused. Can I try to clarify?
thepumpguysc, look on page 20, in the photo of 138.4 KB, there is a brass elbow with fitting removed. (Is circled in red). Is that the elbow you want filled with fuel?

 

[thepumpguysc]

OK.. I'M up to speed now.. Yes, thats the fitting..
I was under the impression it was a DBGFC pump.. U have DB2-

 

[Dodgewade]

Lots of time at work, dealing with the holidays, and currently out of town has keep me away from checking on it as i really need/want too. Plan to work on it after Christmas.
Question; it seems when i pulled the cover from over the batteries several weeks ago looking at somthing and it had two batteries. I know i had 12V when i checked the voltage at the pump. So i likely have two six volt batteris? If it does can i charge it with jumper cables from my truck? The batteries are spinning it over rather good, but i know this will not hold out long if it doesn't start.
I really do appreciate the advice.

 

[Vetech63]

This is showing some promise!

 

[Delmer]

You have 2 12 volt batteries in parallel, you can charge it with jumper cables from your truck. Look at the batteries, both have six cells/caps, and the pos is hooked to pos, and the neg is hooked to neg and both to ground, that makes 12V, amperages add together.

If you get the fuel flowing, then you shouldn't have any trouble getting it to start, assuming the fuel is blocked somewhere and the injection pump is still good, maybe shouldn't assume that yet. Don't keep cranking it if the fuel is not flowing, figure out where it's blocked.

 

[Dodgewade]

Took a week off, went out of town a couple day to come back with the flu. Took the wife to a doc in the whole out of town, come home Christmas eve, day after Christmas both of us went to the doctor, she has type A and I have type B. And both are contagious, so it's possible for both of us to catch the others and be sick even longer.
Even of the small stuff. I finally got it out of the pasture so I'm not messing with a gate when I back and forth.

I took the supply line loose from the injector pump added a short piece of clear hose to the pump fitting and filled it with fuel so I could watch what the fuel done. My son cranked the engine over a about five seconds and the pump sucked all the fuel in the hose right on out.

I took the supply line loose from the transfer pump and blew air back into the tank. The is a black cap on top of the filter that can be taken off and I did. While this was off, we hand pumped the small pump until we got some fuel back to this point. I noticed when I would pump it we would get some fuel, but it would go back down between strokes, like it had a check valve that wasn't holding. I put the cover back on top of the filter and started pumping (by hand), but the lever on the pump doesn't seem To get hard like it's building much pressure. You can pump on it several times and crack a line and there's not pressure or air escaping. I think when I took the line loose from the Injector pump and we were pumping by hand we was only getting the fuel in the line draining to the pump since it lower ft Han the filter. I put the fuel line back on the injector pump and tried pumping by hand for a minute or so. Then crack the line and some fuel would run out if I loosened it a few rounds. It never really seemed to build any kind of pressure. This doesn't seem right and sorta leaves me thinking the transfer pump make have took a crap. I know when I change filters on my MF tractor h you can pump it by hand and crack a line at the filter and you can see and hear fuel and air escaping.

I had about I wanted (for the day) as it was getting close to dark too. So we loaded up and come back to my shop. So I'm sitting in here chilling with an adult drink listening to the radio.

Maybe this helps clear up the water some. Thanks for any advice as its greatly appreciated.

Wade

 

[Delmer]

yes, that sounds like a problem.

The transfer pump is driven by a lobe on the camshaft, if the cam is in position that it's operating the pump, then you can't operate it with the finger lever. Try rotating the engine and try again to see if you get a longer stroke.

This style of diaphragm pump WILL NOT get hard to pump when it pumps up fuel pressure, the lever does not pump the fuel, the lever and cam PULL the diaphragm BACK sucking in fuel from the supply. If you plug the inlet with your finger and pump, you'll feel it's harder to pump. As the fuel pressure builds, the diaphragm is held back by the pressure, and the lever is only returned by the little return spring, NOT the main diaphragm spring, making it very easy to pump the lever. If you release a little fuel from the pressure side, you can feel the resistance for a partial stroke. There is only a few PSI developed by these pumps, but it will spray if you have a finger over the outlet, or open a fitting, or release air in the system.

Taking the inlet and outlet off the transfer pump and blocking with a finger should make it fairly easy to see if it's functioning. you could try blowing air through it the way it pumps fuel, and checking for debris. They're not that expensive to replace, or you could try an electric transfer pump for testing purposes.

 

[Dodgewade]

yes, that sounds like a problem.

The transfer pump is driven by a lobe on the camshaft, if the cam is in position that it's operating the pump, then you can't operate it with the finger lever. Try rotating the engine and try again to see if you get a longer stroke.

This style of diaphragm pump WILL NOT get hard to pump when it pumps up fuel pressure, the lever does not pump the fuel, the lever and cam PULL the diaphragm BACK sucking in fuel from the supply. If you plug the inlet with your finger and pump, you'll feel it's harder to pump. As the fuel pressure builds, the diaphragm is held back by the pressure, and the lever is only returned by the little return spring, NOT the main diaphragm spring, making it very easy to pump the lever. If you release a little fuel from the pressure side, you can feel the resistance for a partial stroke. There is only a few PSI developed by these pumps, but it will spray if you have a finger over the outlet, or open a fitting, or release air in the system.

Taking the inlet and outlet off the transfer pump and blocking with a finger should make it fairly easy to see if it's functioning. you could try blowing air through it the way it pumps fuel, and checking for debris. They're not that expensive to replace, or you could try an electric transfer pump for testing purposes.

I did have to turn the engine over a few times to get it off the high log so it would pump. If it didn't have any kind of resistance the lever wouldn't return. If it's not raining tomorrow I'll try taking the lines off to see if I can tell if it's working.
We used an air tank to blow air back to the tank to ensure the supply line to the pump was clear. I had the line off or loose on the injector pump and we tried blowing up the tank with air to help push the fuel back to the supply pump and filter. The fuel at the injector pump never got any better while doing this.

 

[Delmer]

Don't know what to say, it sounds like you have a good understanding of the lift pump. The air should have given you some fuel flow, maybe take the lines apart and try the air again to see if it flows much better some places to see where it's blocked. That's if the pump seems to work.

 

[Tinkerer]

Any chance of algae or some other crap plugging or restricting the strainer (#5) in the fuel tank?

 

[Dodgewade]

I thought about the opportunity with algae as a few years back my MF farm tractor quit or just shut down. I started pulling it back to my shop and tried starting it while being pulled and it started right up. This happened three or four times and a friend said it maybe the supply pump. I replaced it with some success, so I thought. It never happened very frequently. After a couple more times of it quitting, I spoke with our company's rolling stock manager. He said it sounded like sometime in the tank that would block the fuel flow. The next time it quit, I pulled the shut off from the tank and drained the fuel out. There was some of the worse stuff came out I had ever seen in a fuel tank. I had always been careful not to pour nasty fuel in it so I was shocked. After removing the tank abs cleaning it out it has been fine. The shop manager said the fuel we are getting now will grow stuff like that of it sits very much.

If I get a break in the rain today, I'll check this too. That's for the fuel piping schematic. I'll put it to good use to.

 

[Tinkerer]

It won't take much to block the screen in the fuel tank. Blowing air through the line back into the tank is a temporary fix at best. Sometimes it doesn't help at all. The crap just gets sucked right back into the screen like you have or into the lift pump if there is no filter between it and the tank.
I always preferred to put 2 to 4 psi of air pressure into the tank and force fuel and whatever else is in the tank out of the outlet opening. In your case the screen has to be removed first.
I have had many experiences with Caterpillar scrapers and dozers when there were rags in a fuel tank.

 

[Delmer]

Good catch Tinkerer, that screen will work fine with a lot of gunk on it, then flatten and block off the inlet, causing it to die faster than Thepumpguy was expecting for fuel starvation. The rubber hose will be cracked through by now if it's original, when the screen sucks flat, the hose sucks air, you're dead in the water.

If the hose is cracked, you can grind the ferrule off the fitting and put a new fuel line on the o ring flat face fitting with hose clamps, then run it into a clean jug of fuel for testing purposes.

 

[Dodgewade]

Finally got a break from the six - seven twelve hours at work so I got to work on the backhoe a while.

I replaced the transfer pump, pulled the line from the tank, cleaned it (was dirty/coated). Still didn't seem to get fuel as it should. The line from the tank to the small was removed, put it back on the pump and put the other end in a fuel can. It seemed to pump up easier, but I did get fuel to the injector pump.
Then I cracked/loosen three injector lines at the pump, started it with a little ether and kept it running long enough to loosen the supply line to the injector pump and it was pushing a lot of fuel out. Tightened it back and never got any fuel to the loosened injector lines.
So I'm probably looking at a bad injector pump?
Any suggestions?

 

[Dodgewade]

The line from the tank to the small was removed.

Meant to be the line from the tank to the transfer pump was removed.

 

[Dodgewade]

How can the shut off solenoid be checked?

 

[thepumpguysc]

It should CLICK when u turn the key..
If u cant hear it, u might "feel it" when the key is cycled..