Priming injector pump

[Ripper]

I have an 843 desiel that I ran out of fuel. I cant get it to start after adding fuel and bleeding air through the filter cannister. This thing is new to me and I cant find a way to bleed lines through the pump. I have no manual to look at either. It appears as though the pump is built into the engine to me. Can some body tell me how to get the air out of the system? This bobcat was loaned to me and the owner is out state. He told me there is a blead valve on the pump but I can't locate it by following the line from the filter housing up the side of the motor and to the injectors.Thanks Rip

 

[skidsteer.ca]

There shoud be a primer bulb (like a boat motor uses) in the fuel line before the fuel filter. There is usually a bleed screw on top of the filter canister, and there should be another one where the fuel line comes into the injection pump. This has a Isuzu motor, I believe, should be just like my 853.
Ken

 

[Tazza]

There shoud be a primer bulb (like a boat motor uses) in the fuel line before the fuel filter. There is usually a bleed screw on top of the filter canister, and there should be another one where the fuel line comes into the injection pump. This has a Isuzu motor, I believe, should be just like my 853.
Ken

Like Ken said, there will be a primer bulb in the fuel line, there should also be a bleed valve on the injector pump. Open this and pump the hand primer, fuel should flow back to the fuel tank and the lines should be purged of any air. There will be air in the lines to the injectors but that will purge its self. Ensure you tighten the bleed screw or the engine will not run.
The bleed valve on the Kubota and Peugeot engines is on the injector pump where the fuel comes in and there is a small hose running to the tap off lines to the injectors (small rubber hoses that link them together). Thats a good way to trace where the valve should be, look at where the hoses run to. I hope the Isuzu runs the same basic setup. Good luck.

 

[Fishfiles]

Like Ken said, there will be a primer bulb in the fuel line, there should also be a bleed valve on the injector pump. Open this and pump the hand primer, fuel should flow back to the fuel tank and the lines should be purged of any air. There will be air in the lines to the injectors but that will purge its self. Ensure you tighten the bleed screw or the engine will not run.
The bleed valve on the Kubota and Peugeot engines is on the injector pump where the fuel comes in and there is a small hose running to the tap off lines to the injectors (small rubber hoses that link them together). Thats a good way to trace where the valve should be, look at where the hoses run to. I hope the Isuzu runs the same basic setup. Good luck.

Sounds like you may be new to priming diesels , if all the information giving so far still don't get you going then crack open the 4 injector supply tubing nuts on top the motor on the injectors about 1/2 turn and spin the motor over with the key on and you should start to see bubbles or fuel pretty quick after you followed the procedures in the previous post , if you don't you may have another problem stopping the fuel , like a run /kill solinoid , wiring or power problem , broken pickup tube , clog in the fuel line or the check vavle that is built into the hand primer bulb

 

[Ripper]

Sounds like you may be new to priming diesels , if all the information giving so far still don't get you going then crack open the 4 injector supply tubing nuts on top the motor on the injectors about 1/2 turn and spin the motor over with the key on and you should start to see bubbles or fuel pretty quick after you followed the procedures in the previous post , if you don't you may have another problem stopping the fuel , like a run /kill solinoid , wiring or power problem , broken pickup tube , clog in the fuel line or the check vavle that is built into the hand primer bulb

First off thanks for the tips. I have cleared the cannister of air by pumping the bulb and bleeding it through the screw on top like a person bleeds a brake system. The line leaving the cannister goes to the side of the block through a banjo fitting to what I assume is internal injector pump head then on to each sucessive pump head. I loosend the compression nut and pumped fuel through this line. I cant locate any type of bleed valve on the rubber lines that are all tied together and go around toward the back side of the engine. If I was to loosen the nuts on the injectors would the pump function as having check valves to keep the system full of fuel after cranking? Do I understand what Im seeing please correct me if Im wrong. This unit pulls fuel from the tank by the injector pump rotating creating a suction on the line. Once the fluid gets through the pump head it fills the line to the injector creating back pressure in the line. Once the line is full the injector fires when pump rotates. I dont understand how the rubber tubes come into play. Also how does the throttle regulate the fuel? If some one has the time please enlighten me. Thanks Rip

 

[Fishfiles]

First off thanks for the tips. I have cleared the cannister of air by pumping the bulb and bleeding it through the screw on top like a person bleeds a brake system. The line leaving the cannister goes to the side of the block through a banjo fitting to what I assume is internal injector pump head then on to each sucessive pump head. I loosend the compression nut and pumped fuel through this line. I cant locate any type of bleed valve on the rubber lines that are all tied together and go around toward the back side of the engine. If I was to loosen the nuts on the injectors would the pump function as having check valves to keep the system full of fuel after cranking? Do I understand what Im seeing please correct me if Im wrong. This unit pulls fuel from the tank by the injector pump rotating creating a suction on the line. Once the fluid gets through the pump head it fills the line to the injector creating back pressure in the line. Once the line is full the injector fires when pump rotates. I dont understand how the rubber tubes come into play. Also how does the throttle regulate the fuel? If some one has the time please enlighten me. Thanks Rip

I kinda take it you didn't get running yet , I think I never really gave the complete bleed procedure , whne the nuts are loosen on the top of the injectors and the motor spin the pump will send fuel up to the injectors , all air will be expelled and then you should start seeing fuel , when you see the fuel you start closing off the injector flare nuts on the ones that you see fuel , usually the engine will start running before all nuts are closed and squirt you in the face , at this point it's stand to the side or get sprayed , when it starts to kick over I will stop cranking and close all nuts and then start it up ------I can't remember if the engine you have has a lift pump or not , but almost all diesels do , it's a fuel pump that sucks the fuel from the tank and delivers it to the injector pump -----------have to go to a wake and then a Christmas party

 

[skidsteer.ca]

I kinda take it you didn't get running yet , I think I never really gave the complete bleed procedure , whne the nuts are loosen on the top of the injectors and the motor spin the pump will send fuel up to the injectors , all air will be expelled and then you should start seeing fuel , when you see the fuel you start closing off the injector flare nuts on the ones that you see fuel , usually the engine will start running before all nuts are closed and squirt you in the face , at this point it's stand to the side or get sprayed , when it starts to kick over I will stop cranking and close all nuts and then start it up ------I can't remember if the engine you have has a lift pump or not , but almost all diesels do , it's a fuel pump that sucks the fuel from the tank and delivers it to the injector pump -----------have to go to a wake and then a Christmas party

Once I blead mine at the filter and tthe banjo nut at the injection pump it kicked right off.
The rubber lines your seeing up around the injectors ant the other rubber lines at the pump are just returns to the fuel tank. There is 1 wire on the injection pump, it should have 12 volt + positive with the key on.
Ken

 

[Ripper]

Once I blead mine at the filter and tthe banjo nut at the injection pump it kicked right off.
The rubber lines your seeing up around the injectors ant the other rubber lines at the pump are just returns to the fuel tank. There is 1 wire on the injection pump, it should have 12 volt + positive with the key on.
Ken

I have pumped fuel through the last banjo fitting( end of the supply line). Loosend injector supply nuts.I have two wires connected to the pump (black and Red) red is hot with the key on. I cranked it over several times and got nothing through the pump to the loose lines going to the injectors. I checked the fuses located buy the pump all look ok. I checked the relays located above the battery for corrosion. Three were clean the one labled glo plugs was all corroded I cleaned it up and reasembled it . Then cranked again and had no fuel flow. I then swapped relays (break and glow plug) got the same result with no fuel bing pumped but I DID NOTICE THat the bobcat felt like it was trying to move as I cranked the engine over. I put the relays back where I started and quit for the day. What should I try next? How much is it to have a service call from a bobcat mechanic? I hate to call some one as I have never had much luck with service calls. It gets under my skin if I have to pay someone to guess at what a problem is?

 

[Fishfiles]

I have pumped fuel through the last banjo fitting( end of the supply line). Loosend injector supply nuts.I have two wires connected to the pump (black and Red) red is hot with the key on. I cranked it over several times and got nothing through the pump to the loose lines going to the injectors. I checked the fuses located buy the pump all look ok. I checked the relays located above the battery for corrosion. Three were clean the one labled glo plugs was all corroded I cleaned it up and reasembled it . Then cranked again and had no fuel flow. I then swapped relays (break and glow plug) got the same result with no fuel bing pumped but I DID NOTICE THat the bobcat felt like it was trying to move as I cranked the engine over. I put the relays back where I started and quit for the day. What should I try next? How much is it to have a service call from a bobcat mechanic? I hate to call some one as I have never had much luck with service calls. It gets under my skin if I have to pay someone to guess at what a problem is?

I am thinking you got a Perkins or possibly a Isuzu in the 843 and it sounds to me from what you done so far that it could be the fuel shut off solinoid which should be the solinoid that the red and black wire you mentioned goes to , not sure in my head which set up you got but you can unsrcrew the solinoid out of the injection pump and there is a plunger and a spring inside , with the solinoid off the machine in your hand and the wires hooked up and key on you should be able to see the plunger get pulled and helded in , on some pumps you can start up and run the engine with the solinoid off the engine and use your finger or a screw drive to push the lever and kill it to verify that was the problem , but I don't think the 843 was like that and fuel will leak if ran with it not hooked up , that banjo fitting you were talking about did you look thru it when it was off , have seen some screens hidden inside of the bolt that holds the banjo , it is possible that the pump is bad --------------try force feeding it as you might have a slug of water or dirt blocking up the injection pump , take a can of clean fuel , with a hose and primer bulb hooked directly into the inlet of the injection pump , pump it by hand as you spin it over with the injector nuts broke open , also disconnect the return line that goes back to the tank and be sure it is not blocked up as some diesel engines will not run if back pressure is on the return line , JD is notrous for that

 

[Ripper]

I am thinking you got a Perkins or possibly a Isuzu in the 843 and it sounds to me from what you done so far that it could be the fuel shut off solinoid which should be the solinoid that the red and black wire you mentioned goes to , not sure in my head which set up you got but you can unsrcrew the solinoid out of the injection pump and there is a plunger and a spring inside , with the solinoid off the machine in your hand and the wires hooked up and key on you should be able to see the plunger get pulled and helded in , on some pumps you can start up and run the engine with the solinoid off the engine and use your finger or a screw drive to push the lever and kill it to verify that was the problem , but I don't think the 843 was like that and fuel will leak if ran with it not hooked up , that banjo fitting you were talking about did you look thru it when it was off , have seen some screens hidden inside of the bolt that holds the banjo , it is possible that the pump is bad --------------try force feeding it as you might have a slug of water or dirt blocking up the injection pump , take a can of clean fuel , with a hose and primer bulb hooked directly into the inlet of the injection pump , pump it by hand as you spin it over with the injector nuts broke open , also disconnect the return line that goes back to the tank and be sure it is not blocked up as some diesel engines will not run if back pressure is on the return line , JD is notrous for that

I got it running. Thanks to all that helped me in the learnings. The trouble came from the connector at the fuel solonid. One of the spades was burnet. the spade was burnet to the point that it was short and would only reach when I pushed in on it with my thumb. I used a wire spade terminal cut down to join the two when I plugged it back together.

 

[skidsteer.ca]

I am thinking you got a Perkins or possibly a Isuzu in the 843 and it sounds to me from what you done so far that it could be the fuel shut off solinoid which should be the solinoid that the red and black wire you mentioned goes to , not sure in my head which set up you got but you can unsrcrew the solinoid out of the injection pump and there is a plunger and a spring inside , with the solinoid off the machine in your hand and the wires hooked up and key on you should be able to see the plunger get pulled and helded in , on some pumps you can start up and run the engine with the solinoid off the engine and use your finger or a screw drive to push the lever and kill it to verify that was the problem , but I don't think the 843 was like that and fuel will leak if ran with it not hooked up , that banjo fitting you were talking about did you look thru it when it was off , have seen some screens hidden inside of the bolt that holds the banjo , it is possible that the pump is bad --------------try force feeding it as you might have a slug of water or dirt blocking up the injection pump , take a can of clean fuel , with a hose and primer bulb hooked directly into the inlet of the injection pump , pump it by hand as you spin it over with the injector nuts broke open , also disconnect the return line that goes back to the tank and be sure it is not blocked up as some diesel engines will not run if back pressure is on the return line , JD is notrous for that

Its usually quite simple once you find the trouble. Now your that much wiser instead of that much poorer!
Happy New Year
Ken

 

[Fishfiles]

Its usually quite simple once you find the trouble. Now your that much wiser instead of that much poorer!
Happy New Year
Ken

Don't take it seriously but jokingly , a saying comes to mind from your rejoying of finding the problem ---------------" A blind hog finds an accorn every now and then "