853 isuzu fuel starvation

[nrgmoto]

now that it is cold out -10 to +20f, my 853 needs help staying running by pumping the hand primer. I go back and forth from fuel lever to pumping for about 15 minutes until finally it draws fuel on its own and I can plow with it. This happened last winter and I got by, and all summer no problems, but now problem again. I have good winter fuel and additive, replaced hand pump last winter, and tried 3 new fuel filters. Is there an electric helper pump? I would think its mechanical pump would either work or not? Also, could it be an air leak in the line that is ok in summer warmth? Thanks for input

 

[Tazza]

Just wondering if your lift pump on the engine is becoming weak? I see no problem installing an electric fuel pump inline with the fuel line though.

 

[Gregoryoconnor]

Try running it with the fuel cap off. could be a slow vent ???? a slow vent will also make it suck hard and open up air leaks inline that otherwise would not let air in. GregoryO'Connor ScotsBobcatLandscape SoCal

 

[m610]

Try running it with the fuel cap off. could be a slow vent ???? a slow vent will also make it suck hard and open up air leaks inline that otherwise would not let air in. GregoryO'Connor ScotsBobcatLandscape SoCal

My 843 also has an isuzu but it has no lift pump. It's just gravity feed through the primer bulb to the filter and then the injection pump. I would check the filter and then the lines. They often use a Japanese "Diesel Kiki" injection pump that is prone to issues. A damaged fuel hose can suck air in making starting difficult and causing the engine to stall under load.

 

[skidsteer.ca]

My 843 also has an isuzu but it has no lift pump. It's just gravity feed through the primer bulb to the filter and then the injection pump. I would check the filter and then the lines. They often use a Japanese "Diesel Kiki" injection pump that is prone to issues. A damaged fuel hose can suck air in making starting difficult and causing the engine to stall under load.

If the engine has a fuel return line coming from the injection pump. submerse the end of that line ito a pail of fuel and look for air bubble coming out the return line while the engine runs. This will tell you if it has a air leak on the suction side. If thats good , its not a air lock on the fuel tank as a result of a blocked vent, and it otherwise run good. I'd install a electric lift pump and run it that way until the injection pump no longer functions. If its like mine the lift pump is build into the injection pump and in my experience digging into one of those is spendy.
Ken

 

[nrgmoto]

If the engine has a fuel return line coming from the injection pump. submerse the end of that line ito a pail of fuel and look for air bubble coming out the return line while the engine runs. This will tell you if it has a air leak on the suction side. If thats good , its not a air lock on the fuel tank as a result of a blocked vent, and it otherwise run good. I'd install a electric lift pump and run it that way until the injection pump no longer functions. If its like mine the lift pump is build into the injection pump and in my experience digging into one of those is spendy.
Ken

I will try the return line looking for bubbles with my old lines. Here is what I did- I bypassed every thing and put a homeade tank above the radiator with a new line directly into the mechanical pump fitting. It works fine like that. I noticed that the old fuel line coming from the tank barely trickles out, even after removing the primer bulb. Using the bulb, it flows pretty good only when I squeeze it. I tried with the fuel cap off, also. I think my problem is before the primer bulb and back to the tank. Looks like there is no way to remove and replace stuff unless the tank is out, unfortunately. For this winter I'll probably be THAT GUY with a cobbled tank on the back! Thanks for all your help.

 

[mllud]

I will try the return line looking for bubbles with my old lines. Here is what I did- I bypassed every thing and put a homeade tank above the radiator with a new line directly into the mechanical pump fitting. It works fine like that. I noticed that the old fuel line coming from the tank barely trickles out, even after removing the primer bulb. Using the bulb, it flows pretty good only when I squeeze it. I tried with the fuel cap off, also. I think my problem is before the primer bulb and back to the tank. Looks like there is no way to remove and replace stuff unless the tank is out, unfortunately. For this winter I'll probably be THAT GUY with a cobbled tank on the back! Thanks for all your help.

I have read a lot about the fuel pick up tubes inside the tank rotting on these models. I think there is a small filter on the end of the pick up tube. Mike