Bobcat fuel line problem

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horseman

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Mar 28, 2007
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Hi, I own a Bobcat 863, has less that 2k, this afternoon it started to sound as if I am running out of fuel, I stopped and look, there was fuel on the Engine. I couldn't figure out excatly wher it's coming from, The fuel was as high up as the fuel high pressure line nut, so I'm assuming it could be leaking from around the nut. Tried to tighten the nut 2 and 3, which looked to be wet with fuel, they were tight. anyone had similar problem? or any one knows if I'm suppose to replace the 2 fuel line? Thank you.
 

Fishfiles

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Feb 8, 2007
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Could be the return hoses leaking , last week I changed all the hoses on a 873 , one of the return lines rubbed a hole where it was rubbing against the nut which holds the banjo crossover tubes to the head
 

horseman

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Mar 28, 2007
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Could be the return hoses leaking , last week I changed all the hoses on a 873 , one of the return lines rubbed a hole where it was rubbing against the nut which holds the banjo crossover tubes to the head
Thank you, it was the return hoses, I replaced all, no more leaks, however... the problem still exist. I drained all of the fuel, thinking that the problem is bad fuel or dirt, and replaced the fuel filter.... crancked it.... still acting as if it's taking air in.... left it for a minute on high, then everything was ok for about 10 minutes, , then all the sudden, it started acting up. tried to get all of the air out thru the filter vent.... cranked it, didn't start very good, but after blasting for a minute, it got better, worked on it for about 20 minutes, it was on and off the whole time... then it got to the point that I had the throtle all the way and the engine is hardly staying on.... then it died, cranked it again... Engine will start but very low and then dies again. never had this problem before, anyone has any suggestion? Thank you for your help.
 

Tazza

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Thank you, it was the return hoses, I replaced all, no more leaks, however... the problem still exist. I drained all of the fuel, thinking that the problem is bad fuel or dirt, and replaced the fuel filter.... crancked it.... still acting as if it's taking air in.... left it for a minute on high, then everything was ok for about 10 minutes, , then all the sudden, it started acting up. tried to get all of the air out thru the filter vent.... cranked it, didn't start very good, but after blasting for a minute, it got better, worked on it for about 20 minutes, it was on and off the whole time... then it got to the point that I had the throtle all the way and the engine is hardly staying on.... then it died, cranked it again... Engine will start but very low and then dies again. never had this problem before, anyone has any suggestion? Thank you for your help.
That defiantly sounds like a fuel problem, mine does that when i run it out of fuel, it would bog down and you increase the throttle and still running bad then stall.
I would try hooking up a bottle of fuel and connect a fuel line directly to the lift pump. It will be a bit hard to get it to prime without a primer bulb but it should get there. See if it runs smooth, if so you may have a crack in your pick up from the tank or a leak between the tank and the lift pump allowing air in.
The other thing is it could even be a weak lift pump.
Try running the machine, even if you get someone to sit in the drivers seat and when it plays up give the primer bulb a squeeze, if the revs pick up its your lift pump, as its not getting enough pressure to the injector pump.
 

Fishfiles

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Thank you, it was the return hoses, I replaced all, no more leaks, however... the problem still exist. I drained all of the fuel, thinking that the problem is bad fuel or dirt, and replaced the fuel filter.... crancked it.... still acting as if it's taking air in.... left it for a minute on high, then everything was ok for about 10 minutes, , then all the sudden, it started acting up. tried to get all of the air out thru the filter vent.... cranked it, didn't start very good, but after blasting for a minute, it got better, worked on it for about 20 minutes, it was on and off the whole time... then it got to the point that I had the throtle all the way and the engine is hardly staying on.... then it died, cranked it again... Engine will start but very low and then dies again. never had this problem before, anyone has any suggestion? Thank you for your help.
The fuel pick up tube is originally out of soft plastic tubing and had a screen on the end of it , the screen may be clogged up , the tube will crack and or break off and fall into the tank , sometimes if the tank is full it wil run fine till the fuel level gets to the crack or break , also sometimes the original tube was replaced with the upgraded hard plastic pick up tube but the old tube is still in the tank and it deteriorates and little pieces of the old tube get stuck in the 90 degree fitting coming out the tank on the fuel pick up tube , the replacement for the tube doen't use the screen , and on that model machine it is pretty hard to get it out and back in , to test if the fuel pick up is your problem you can take a gallon jug of diesel and tie wire it to the engine , put a hose from fuel can to the primer ball , prime and start engine and see if it solves the problem
 

skidboy

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Jan 3, 2007
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The fuel pick up tube is originally out of soft plastic tubing and had a screen on the end of it , the screen may be clogged up , the tube will crack and or break off and fall into the tank , sometimes if the tank is full it wil run fine till the fuel level gets to the crack or break , also sometimes the original tube was replaced with the upgraded hard plastic pick up tube but the old tube is still in the tank and it deteriorates and little pieces of the old tube get stuck in the 90 degree fitting coming out the tank on the fuel pick up tube , the replacement for the tube doen't use the screen , and on that model machine it is pretty hard to get it out and back in , to test if the fuel pick up is your problem you can take a gallon jug of diesel and tie wire it to the engine , put a hose from fuel can to the primer ball , prime and start engine and see if it solves the problem
This model has a lift pump which has a filter in it .I think it has a screw that you undo and the black cover pulls of the end of the pump.Ckeck whats in the filter.
 

horseman

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Mar 28, 2007
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The fuel pick up tube is originally out of soft plastic tubing and had a screen on the end of it , the screen may be clogged up , the tube will crack and or break off and fall into the tank , sometimes if the tank is full it wil run fine till the fuel level gets to the crack or break , also sometimes the original tube was replaced with the upgraded hard plastic pick up tube but the old tube is still in the tank and it deteriorates and little pieces of the old tube get stuck in the 90 degree fitting coming out the tank on the fuel pick up tube , the replacement for the tube doen't use the screen , and on that model machine it is pretty hard to get it out and back in , to test if the fuel pick up is your problem you can take a gallon jug of diesel and tie wire it to the engine , put a hose from fuel can to the primer ball , prime and start engine and see if it solves the problem
Thank you all, I disconnected the fuel line at the priming bulb and stuck a diesel bottle, the machine worked fine. so I'm assuming there is something clogged in the tank...the tank cap is open and no fuel dripping off the hose coming from the tank. in few minutes I'm going to attemp to blow 100 psi air into the hose into the tank to see if that might push the dirt away from the screen. how hard is it to replace the hose/screen inside the tank?
 

2109 Stang

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Nov 8, 2006
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Thank you all, I disconnected the fuel line at the priming bulb and stuck a diesel bottle, the machine worked fine. so I'm assuming there is something clogged in the tank...the tank cap is open and no fuel dripping off the hose coming from the tank. in few minutes I'm going to attemp to blow 100 psi air into the hose into the tank to see if that might push the dirt away from the screen. how hard is it to replace the hose/screen inside the tank?
Be carefull you don't blow your fuel tank apart with that much air presure.
 

horseman

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Mar 28, 2007
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Be carefull you don't blow your fuel tank apart with that much air presure.
I had the cap open to make sure that doesn't happen. I cannot get fuel from the tank though it's almost full, priming it is not working either, yet when I push air thru, I can hear it in the tank. any has an idea what's going on?
 

Tazza

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I had the cap open to make sure that doesn't happen. I cannot get fuel from the tank though it's almost full, priming it is not working either, yet when I push air thru, I can hear it in the tank. any has an idea what's going on?
My pickup has a ball that sits at the end to prevent fuel draining out. Yours may have the same 1 way valve that will prevent you from blowing are through it that way.
 

horseman

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Mar 28, 2007
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My pickup has a ball that sits at the end to prevent fuel draining out. Yours may have the same 1 way valve that will prevent you from blowing are through it that way.
I'm sure the fuel pickup I have is a one way valve. I still cannot get anything out of the fuel tank, though the Tank is almost full, any suggestion on how to get the fuel to flow, priming it is not working. second, how do I access the fuel line that runs from the tank to the priming bulb to replace it? Thank you.
 

siduramaxde

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Nov 15, 2005
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I'm sure the fuel pickup I have is a one way valve. I still cannot get anything out of the fuel tank, though the Tank is almost full, any suggestion on how to get the fuel to flow, priming it is not working. second, how do I access the fuel line that runs from the tank to the priming bulb to replace it? Thank you.
If I remember correctly, on the 863, the motor is on top of the fuel tank. I think to remove the fuel tank the motor/pumps must be removed. Sorry for the bad news.
 

Fishfiles

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Feb 8, 2007
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Pull the pick up tube out the tank , it is pretty hard to do on a 863 , espescally if you never done it before , it's between the motor and the pump, it is held in with a rubber grommet and has a 90 degree fitting that pushes in to the grommet , , the old style tube was clear tubing like aquarium tubing and had a screen wth a check in it , the new style is hard plastic no screen , if you bought the machine used or it had been worked on before for the pickup tube , it is possibe that the old tube which falls off in the botom of the tank has discinergrated into little pieces which sometimes gets stuck in the 90 degree fitting , have also seen on some s/n breaks of the 863 where the fuel line is run under the engine and the motor mount rubbers get weak and pinch the hose , but you seem to have the pick up tube senerio
 

dean3

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Dec 14, 2007
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I had an 873 with the same problem. After 6 weeks of screwing around & taking stuff apart I realized that the primer had actually gotten soft. The machine would start up fine, run it for a little while and the primer bulb would squeeze down flat pinching off the fuel line. I assumed it was something between there and the tank. When I finally replaced the bulb it ran fine.
 
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