This is the 2nd machine in 1 week with problems. This one I am thinking is the injection pump. I crack open the lines at the injectors and get just a small dribbling stream of fuel coming out. I would assume this would be much more since it should be high pressure?? The machine just stopped running when it died. I thought maybe I had air or gelled fuel but that doesn't seem to be the case. Anybody have any info/experience with this? How much pressure or psi should there be at the line on the injector itself? If it is the pump who has them (besides dealers) or who rebuilds them? Thanks all.
Still no results here. I have been trying different things last night and this morning and still no change. Is the injection pump the only pump on the machine?? Or is their a fuel pump and an injection pump?? Is/Are they belt driven or gear driven? Any ideas? anyone Thanks to all (by the way Bobcat 773 G turbo 2.oL Kubota)
Bobcats are prone to a variety of fuel problems. Some have found the fuel pickup line in the tank has broken off. How much fuel is in it? Does it have a primer bulb in the fuel line? these can crack and allow it to suck air. It should have a transfer pump to supply fuel to the injector pump. Have you changed the filter and refilled the new one? Could have water in a low spot on the line that froze and made an ice cork blocking the fuel flow.
I have put on 2 new filters with power service in them. I can pump up the primer ball rock hard, hit the key and it turns over like its going to fire up any second but never does. When I get out and check the ball it's still rock hard. I think the pickup tube is good as the primer ball stays firm and when I bleed the system I never seem to lack fuel(tank is just under full).The machine has been in my shop at 40 degrees for 6 straight days. Thanks for the help
Is the fuel shutoff solenoid operating? If you can pump up the primer bulb rock hard, it should run at least for a moment even if the lift pump isn't operating. Sounds like the solenoid is not turning on the fuel.
Atco is right on with the fuel solenoid, when you turn the switch on have some watching to see if its activating.... should be able to hear a click also.
Your right grandpa. Heck, if nothing else, I'd tie back the fuel lever with tie wire and see if it fires off. If it does, well...now you know what needs fixin'.
Atcoequip I made sure the solenoid was opening and closing. I have even manually opened it and had someone hold it open. I am at a loss here? anything else? If you pump the primer up hard is that really enough pressure to open the injectors to allow enough fuel for it to run?
If you look close around your injector pump you should see a little round knob, open it a couple turns and then sqeeze your primer bulb to see if it will flow fuel out that way.
Grandpa I have removed the small bleed line after the bleeder knob and I get fuel out of there. I have even removed the line off the last injector before the overflow goes back to the tank and I get fuel there as well.
Darn...beat me to it! I was fixin to say that granpa! Heck, let's just go through the whole thing and see if we can fix this critter. :yup Hmmm, interesting. Before we condemn the injection pump, let's start over with a few basic things. First, disconnect the fuel line coming out of the primer bulb. Aim the primer bulb at a container and make certain that it pumps fuel when you squeeze it. If good, re-connect hose. Disconnect hose coming out of lift pump. Sqeeze primer bulb and see if fuel comes out of lift pump outlet. If good, crank engine a few strokes and see if lift pump moves fuel out of outlet. If good, just to cover all bases, disconnect fuel supply line where it connects to injection pump. Squeeze primer bulb and see if fuel comes out of hose. If good, remove the fitting that goes into injection pump and make sure it's not clogged. Your just checking every crazy thing that could be a problem. Lastly, remove the hose connected to the fuel return valve on the injection pump. That's the valve on the side of the injection pump that granpa mentioned that has a knob on it. Remove the hose on the valve, turn the knob CCW until it stops, and squeeze primer bulb, you should have a small amount of fuel coming out of fitting. If not, remove fitting, sqeeze bulb and see if fuel comes out of hole.
Take the air cleaner out maybe ya got an obstruction in there.
If you got fuel to the injectors and air the da.......rn thing has gotta run!
Air cleaner is out. I have fuel everywhere mentioned. I have gone as far as removing the lines off the injectors themselves and cranking the motor over. I am getting fuel there but it is not much pressure just a steady little flow. Do you know what psi those lines should be under? In my knowledge of diesel engines with idi engines psi ranges are 300-500 psi.
scratching my head")
I am wondering if I am getting some fuel but do not have enough line pressure from the injection pump to fully open the injectors and they are just weeping out enough fuel to make the machine smoke and feel like it's ready to run.
And i dont know what the psi to the injectors should be offhand either.
have you tried ether on it?
Are there any tests I can do to check the injection pump itself?
Yeah I ethered it a couple times and doesn't seem to do anything
I have never been into a bobcat pump so im in uncharted territory there. sorry
Go to the chat siedow we can work faster there.
Sorry granpa...had to walk dog. LoL siedow, remove the valve cover and make sure the valve train is operating. There is another thread going right now about a Bobcat that has the pressed on cam gear spun off the cam...nothing operating. It's worth a look.
Atco that other thread is mine. That is one of my other machines. That is the first thing I checked
Grandpa I tried to get into the chat but can't for some reason.
Do you have Javascript operating on your computer? It's required to get in chatroom
Well, that does change things a bit. Back to injection pump. Pressure is irrellevant without flow. It works something like this; with engine on #1 piston at timing mark (probably around 8 - 10 degrees BTDC), you should be able to remove #1 injection line, tie back fuel shutoff, open throttle fully, and pump primer bulb. Fuel should flow out of #1 port as you manually turn engine over and reach timing point and it should continue to flow by hand pumping until you near TDC of #1 piston. You don't worry about pressure until you obtain flow from injection ports. I think the next thing I'd try is removing the throttle control and shutdown control plate on the side of the injection pump. You could have linkage has come loose or something. If I didn't see anything suspect there, I'd pull the injection chamber plate from top of pump housing and take it to a pump shop and have it tested. That is, if you have made certain that fuel is getting to injection pump as well as coming out return to tank fitting.
Atco I will check out those things and let you know. I still can't get into the chat and I made sure my javascript was enabled(just isn't my week). If you or grandpa would like to talk on the phone tomorrow at some point I am more than open to that. If you don't I understand as well but if that's an option tell me what time and I can call you or give you my number.
Send a private message to digger242j, he'll help you get your chat problem sorted out. My boss keeps me pretty busy during the day to spend much time on the phone. Have you got an injection shop in your area? They would be able to give you info about questions you have about your injection pump, especially if you tell them "could you tell me how to remove this so I can bring it to you to have it worked on". They'll be a little more eager to offer info if they know they're going to get some business out of it. It's not that hard to remove that injection chamber plate. Then you can have it tested to see if that's where your problem is.
Update. OK so here is my assumption. I tore into the injection pump a little today. I took off the covers on the fuel solenoid shutoff and the throttle control shaft into the pump itself. The inside of the mechanical end of the pump looks pretty basic.(almost like a cam setup in an engine that's gear driven) Everything inside the mechanical end looks good and seems to be funcitoning good. I then checked the little diaphragm fuel pump valve on the face of the pump and it works great. I took it out and was able to push the plunger and draw in tons of fuel, and where it was contacting the inside shaft of the pump didn't show any wear. So I then took off the fuel lines attached right on top of the injection pump itself and just to see what happened cranked the motor over for about 20 seconds and only had fuel come out of 1 line. I am going to tear into the top of the pump tomorrow(fuel side) and see if I can determine anything right away. I made some calls to rebuilders with not much luck as far as info, they all wanted to see it on their bench before they would make a diagnosis.
i have rebuilt the injectors and the diesel pump to my 763... it costed about 600 euros.... good luck!
Sorry you having so much difficulty siedow. I just sounds like the fuel isn't being turned on to flow into injector chambers. Have you cranked engine to make sure the injector cam is rotating? Just making sure. When you pulled the shutoff control plate, do you notice a problem with any links that it controls? Any levers of the links maybe have a roll pin missing on a shaft or something? I haven't had one of these apart for a couple of years, can't remember the components in there. When you remove the injection chamber plate, you'll probably have to remove intake manifold, that's what it looked like to me on our 773G. There should be shim plates under that injection plate, make sure you keep up with them.
Atcoequip The injector cam is turning. I checked that out and the fuel shutoff mechanism is working correctly as I manually opened it with the cover off and cranked it over. I haven't torn into the injector chamber plate yet but I did notice that your right about the intake manifold having to come off. I want to open that up but am a little leary about it, that seems a little complex for my knowledge. I am pretty good mechanically but am no injection pump rebuilder. I have made some calls to a mechanic friend with waste management and he may have someone in their shop I can talk too and possibly rebuild this thing on the side or help me do it. I work on most all of my own problems so when I get help with this I will share with all so maybe we can shed some light on any future problems others may have. If anyone has any other info feel free to post; all advice welcome. Thanks guys.
Forgot to put in that the guy at waste mgt that I have been talking to said it sounds like the fuel rack isn't opening as it should. I assume this is in the injector chamber plate
hey siedow, that rack is what I'm thinking might be your problem, might be. The mentioned "rack" is what controls how much fuel feeds the injection chambers. This is what throttles engine. It also kills the engine by stopping flow of fuel into the injector chamber, engine dies. Check all your linkage and controls for the rack in there, that might be your problem. As I recall, it's not difficult to remove the injection chamber plate. It all comes out as a unit. Now, if you remove individual chambers from the plate, it gets tricky to do that. Something best left for an injection shop.
did you ever get it working?
interested in hearing how your problem worked out. i am having almost the exact same issues with my s185. thanks
we have been having problems with our 185 as well. sometimes it runs good, and other times it wont. fuel is not gelled. filters are good. i tried blowing air backwards from the primer bulb to the fuel tank (not through the bulb) and that seemed to help. there is a fuel strainer inside the fuel tank im going to replace that and drain the fuel tank and see if that does anything. [there is also a fuel return line right next to it without a strainer on it] putting a new line on that goes to the fuel tank. try to see if any of the fuel lines are kinked or something. some of the bobcats have check valves in the tank on the fuel inlet and maybe that is bad if it has one. you might wanna try running kerosene and number one diesel. a weak injection pump and lift pump (not sure it has one) would probably still pump fuel with less viscosity. its doubtful your fuel at the injectors would have that much pressure when the engine is not running.
I post here with out reading the last page......... Did this loader just stop running? Was it running ok and failed to start again? Give some history..... I did see that posted anywhere. If you are getting fuel from the injector lines it should start and run. A steady small flow is all you will see from open injection lines....... resistance to flow is what creates pressure. Install the injection lines, push the throttle wide open and crank it over. If the fuel is flowing as you say it will start.
I started at the the beginning by changing my fuel filter and putting heat to the machine because originally i thought i had gelling or fuel line freeze up. the machine was running and i left it for about 10 min while I dumped a load of dirt and came back to it stalled out. If I open the relief valve and pump it 6-10 times then close it, pump it 4-5 more times until it gets good and stiff, it will start and run good and smooth for 10-15 seconds then starts to sputter like its running out of fuel for another 10-15 seconds. I can keep it running, although rough, if i keep pumping the primer bulb but still eventually dies. I have hooked up an auxillary tank to rule out the pick-up line in the tank, but still no change. I have replaced all the fuel lines from the tank all the way through to the injector pump and the return line back to the tank, including the primer bulb. still no change. I replaced the lift pump because the man at bobcat said that must be my problem, still didn't change anything. As a last resort, I installed an electric fuel pump with 5-8 psi direct to the injector pump (only because it had an inline filter) still with the same results. Run for 10-15 seconds then die out. If i bleed the fuel lines at the injectors, I get fuel out of the first 3 fuel lines, the fourth always seems to have air. The fourth being the far right if your standing at the back of machine. I am totally stumped and convinced at this point that its in the injector pump but i am not sure just how far to get into it. I have read a lot of the posts on this site and has been extremely helpful but I am not so sure at this point what to do. One last thing, I did check the main shut-off and it does seem to operate properly. Thanks