I have recently purchased a 1983 John Deere 510D Backhoe. It was a beast for the first 2 days tearing up boulders the size of small cars. Day 3 I refueled the backhoe and it stalled after 2 hours of running it. I have blown back the fuel line to the tank and cracked the window on the injection pump timing cover and still after a couple minutes the backhoe loses power and I cannot get it above 1000 rpm's. Any ideas from you pro's would be great. Thanks
Two basic possibilities, either the fuel system is plugged up like you suspect, maybe cracking the window is to rule out the return fitting plugging too? You can pull the return fitting and inspect it for "coffee grounds", if you find them, you can clean it and run for a little while but you'll need to fix the pump before you need a new engine. If you haven't already, change the fuel filter, check the fuel tank inlet screen, drain the water out of the tank, replace any old rubber hoses on the suction side of the transfer pump. If that doesn't help, run the transfer pump inlet hose into a can of fuel and see if it runs faster.
Is this the common symptom of a faulty pump? Im not interested in destroying the engine. Do you think I should pull the pump and have it rebuilt?
NO, you should figure out what is wrong and fix it, most likely the fuel system is plugged and the pump is fine. If the pump is plugging the return fitting with coffee grounds, then if you REMOVE the guts and continue running it, eventually the governor will lose control and the engine will run away, but you'll have warning to shut it down if you're paying attention, that's a long way off, and not the most likely issue at this point, IMHO.
OK so what do you mean by remove the guts? Its a Stanadyne pump
I posted a picture can you specify which is the return fitting?
i removed the return side fitting and it is just an open fitting no guts so to speak of. I also ran the thing with the timing window open to rule out the return side.
I removed the fitting in location 1 it was empty just a wide open fitting. The timing cover at location 2 was removed and run to rule out the return side. location 3 is the supply side, should i remove the fitting and check the filter inside?
fuel pump looks like it might be the wrong one
3 IS NOT the supply side.. 3 is the RETURN side..THATS WHERE the check ball lives.. 1 is the supply side..
thank you, should i remove it and check for debris, or did the open timing cover rule out return issues?
That clear filter looks mighty "dark" from that angle.. u might think about changing it.. It shouldnt be paper.. The supply pump is electric.. no harm unless its putting out to much pressure.. spec is 1-3 psi.. It looks like the pump has been off & rebuilt at some point, just going by the paint color..
Is there a replacement you would recommend?
if it were mine & I had this problem.. YES I would take it out & using an air compressor, blow it out.. Try running the machine w/ the fuel cap off or loose, also.. have u changed the filters yet.?? dont just blow them out.. replace them..
do a parts search on the JD website for your engine & SEE if it even takes 1.. Someone here will have a link to the JD site..
How about taking the line off at the electric fuel pump & while holding it over a bucket, turn the key on & WATCH the flow for a couple of minutes.. try to SEE if the flow slows down any.. {2-3minutes} Ya never know, maybe the electric pump gets hot & shuts down, restricting the flow to the inj. pump.?? Another thing too.. they dont like 5 gallons at a time in the fuel tank.. IF thats how your running it.. your causing your own problems.. IMO
Troy, did you follow the lines from #1 and #3 back to see where they go? The injection pump takes the fuel in the end and returns it on the other fitting, like THEpumpguy said, but that doesn't mean somebody didn't change them around, obviously this has been messed with recently, and possibly never got to work right, which might be why it was for sale. Obvious clues: non stock filter, pump, hourmeter with 10? hours, rebuilt/different injection pump with different mounting bolt hole drilled (pumpguy?) What's the quick coupler with the hose clamps right in the middle of the pic? I hope that's for "spit swapping" the coolant to start it in winter time. After tracing the lines, how about an explanation, or better yet, pictures of the hose routing from the fuel tank to the injection pump and back again, there could easily be several issues with this one.
the tank is full, however it did get low before i filled it completely
I would STILL check the FLOW like I instructed.. just to rule out a faulty electric pump OR garbage in the tank covering the outlet.. Does the machine ever STOP.?? or does it just slow down.??
so the routing is from the tank to the first filter, through the fuel pump around the motor to the glass filter and then back around the motor to the stanadyne pump. the return side goes to all the injectors and then to the fuel tank. Hour meter reads 8010 hours and i think its accurate as it still runs. The quick connect hose runs to the heater inside of the cab from the radiator
Even better, unhook #1 from the injection pump and turn the key to let that pump run to see how the fuel flows through the whole system. By the way, when tracing the fuel lines, there may be a large hex nut on the fuel tank inlet or just a small fitting down low on the tank, the return should be a smaller line that tees with the return from injectors and goes to the top of the tank. There should be a glass rectangular fuel filter, take that off and shake it and drain the gunk and water out. Is the stock mechanical lift pump/primer pump still in the system? Does it pump by hand? I'd get rid of the electrical pump and small filter if possible, but maybe finish the diagnosis before that. I see on jdparts, that the one bolt in the injection pump flange is correct, wasn't familiar with that one.
which side should i disconnect, I assume you mean after the pump to see if the pump is slowing down when it works due to heat or whatnot
the lines are exactly as you describe. The rectangular glass filter looks clear as could be, no sediment or water in it at all. the manual pump doesnt seem to be here anymore looks like it was replaced with the electric one
I would disconnect #1 at the injection pump, then you see what the injection pump sees. You may need to operate until the engine slows down if this is an intermittent problem. Could be trash anywhere in the system, or the pump getting hot/worn... Is the stock mechanical lift pump/primer pump still in the system? Does it pump by hand? RATHER, can you see where it was? should be a small hole with two bolts or threaded holes on the camshaft area (the injection pump is driven off the camshaft to give you an idea of where the cam is, parallel to the crankshaft low on the engine) Also, did you drain any fuel from the petcok in the bottom of the tank? as far as I know, loosening the timing window and not changing anything means you're dealing with fuel supply, not the plugged return fitting.
So I did not drain any fuel from the tank. I do not see the mechanical lift pump and will take some pics to post and show you
I'm w/ u Delmer.. fuel "supply" problem.
Am I missing something here..?? Theres only 1 line going to or from the stanadyne glass filter.. Does that mean its by-passed.?? & they're only using that small filter by the electric pump.??
OK guys I removed the fuel pump and put the ignition on for a couple minutes. Fuel is barely coming out of this. here is a picture i hope it helps. But i would describe the flow out of the fuel pump as dripping with a very slight spit
the other line is not in view it comes in on the bottom right in the back. it is inline and working
Well.. u found the problem.. SUPPLY.. U might have something clogging the electric pump.?? Take both lines off & get an air compressor to blow thru the electric pump.. Your mouth aint gonna cut it.. Next, take the cap off the tank & blow back from the electric pump w/ shop air.. SLOWLY.. U HAVE TO HAVE a "stream" of fuel.. its not gonna be hi pressure but u NEED a stream.. Like I said, the fuel spec on the pressure is 1-3psi.. low pressure but hi volume. {stream} Good luck.. When u find the clog, you'll know it when the dribble turns to a stream.. OR the electric is bad.. Just for kicks, take off the FEED LINE from the electric & see how THAT flows.. IF its higher, your restriction IS the electric pump.. U DID have the key ON when u checked the flow didnt u.??
LOL, I did have the key on. I will pull the pump now and blow it out as well as the line to the tank. I will let you know the results. Thank you so much
If the stock glass filter is working, why the extra filter? They must be adding some restriction to flow.
I see, you have an electric boost pump.
I just had a similar issue with my 710. Was pretty sure I had just put a fuel filter on not too long ago, and the problem was intermittent - so how could it be the filter anyway?? It was the filter. Don't be like me. Completely 100% rule out the easy and obvious before you start tearing it apart.
In this case, the glass filter base allows you to drain water, and probably bleed the air out the top also, so you can open those to confirm you have the same flow before and after the filter element, that is out of the bottom and the top of the glass bowl base, through the aluminum plugs. they're often loose enough to open by hand, seal with o ring.