After running fine since conquering all the fuel problems last summer, something new: it "runs out of gas" after 20 minutes of regular use even though the tank is nearly full. _____ This has the 4 cyl. ford gas motor. I replaced the fuel filter, repositioned the 1 year old electric fuel pump (that I realized I had mounted higher than the bottom of the tank), shortened up the fuel lines to keep lines and filter above pump, ran with the fuel filler cap removed, even blew the line from filter back into the tank to confirm no blockage; all to no avail. _____ I have a clear filter on and can see that the fuel level in the filter drops to near nothing when the engine stalls. If I leave the beast sit overnight (or until the filter fills up), it'll start and run for another 20 minutes. I can take off the fuel line at the pump inlet and gas pours from the line, apparently without obstruction. After putting the line back on the pump and waiting a while, the fuel filter fills up and I can run another 20 minutes. Any suggestions would be greatly appreciated.
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Yes, gas does feed just not at all enough to feed the engine. I did loosen and even remove the gas cap without a change in symptoms. Well, let me restate that. _____ I know I tested the flow of fuel with the cap loose/removed when the engine was NOT running, I just watched the flow of fuel into the filter, but I may not have tried running the machine with the cap loose. It just occurred to me that with the engine not running there is no draw of fuel to help the flow do more than dribble into the line/filter. _____ Thanks much for the help again, Tazza. I'll try running with the cap loose to see if that help. If it does, is there a way to clean the cap vent or would I need a new cap?
Honestly, i don't know if the cap can be cleaned or not. I'd like to think you could blow it out with air or something.
Hopefully it's something as simple as a cap.
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The 732 doesn't have a pickup tube like the newer 40 series machines do, they just have a port at the bottom of the tank where they draw fuel from. I have heard of occasions on other machines where people have had very similar symptoms to what you have and have found some form of debris (a rag or something similar) in the bottom of their tanks that would shift over and block the outlet and the machine would die, only to restart again after a while and run until the obstruction made its way back to the outlet. Might be something to look into... If you have to remove the tank, you'll need to remove the cab and the back wall between the cab and the tank and then the tank comes right off...
Thanks for the input, fellows. I tested the cap theory; on tight, on loose, or off, makes no difference. My brother-in-law suggested that a fuel line may be separating inside so I replaced all the fuel hose pieces between the tank and fuel pump. Unfortunately, no change in behavior; a few minutes at 1/2 to 3/4 throttle and it's starving for fuel. I can throttle back to a point where the machine will move, albeit very slowly, and it will continue to run. _____ I was not able to get the to get the metal 45 and shutoff valve off the gas tank; not enough strength in my hands to pull it out and afraid to try to twist or pry it lest I break the port. I did blow air into the tank through that valve and did not see anything loose in the tank. When I put everything back together and primed the lines, fuel flowed into the filter rather quickly and filled to what seems to be a normal level. _____ I suppose that I'll find a way to get the 45 and valve off the tank to see if I can find a blockage in the valise, 45, or port. I'd really hate to have to remove the tank, I'm not set up to remove the ROPS.
You know, after lying awake early this morning thinking about this, it occurred to me that while I was draining the tank before swapping out the fuel hoses, using a length of fuel hose attached to the valve, fuel ran out of the tank completely unobstructed. To prime the lines after putting everything back together, I opened the valve and removed the hose from the inlet port of the fuel pump. Fuel appeared to flow into the see-through filter well enough, although I did not allow much fuel to come out of the hose - I just put it back on the pump as soon as it started coming out of the hose. Once all connected, fuel continued to flow into the filter until it filled to a normal level. _____ Then, with the engine running at idle, I can see fuel dribbling into the filter and maintaining that level. When I accelerate, though, the level of fuel in the filter starts dropping and eventually the engine stalls, starved for fuel. _____ I replaced all the fuel hoses between the tank and pump. I did not replace the metal fuel line that runs from one side of the engine compartment to the other but I did blow it out from both directions with the air compressor. I also did not replace the valve and fitting at the fuel tank outlet port but I did blow air through that as well. After all that, I can't imagine that there's any obstructions tank to pump. I also can't imagine that the problem lies in the pump or the hose going to the carb as the fuel pumps out of the filter easily enough. This makes no sense.
It must be driving you mad, you have done everything that i'd do.
The only other thing you can try is to hook up a bottle of fuel and run a hose straight to the pump, see how it performs.
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Just another idea... Next time it does it try to systematically open the gas line up at all connectins working your way back towards the tank. The section where it dribbles on one side and flows good on the other is likely your issue. Hope you get it solved soon.
Well, I'm not sure how I would do that as there is very little room to work in there, not to mention that I don't have the belt/pulley cover. Although, today I did check the general flow upstream of the electric pump by hooking up a length of fuel hose to the outlet of the fuel filter and opening the valve. Fuel flowed out of the filter unrestricted with the tank cap on tight - this would indicate that I do not have any restrictions between the tank and pump. _____ Before doing this, I did run the machine at various speeds and watched the flow through the filter. When I started it, the filter, which sits vertical, was mostly full of gas. The level in the filter dropped quickly but, at idle, the machine kept running. The flow of gas into the filter did not look as strong as it looks when just flowing though as in the test I performed today. I throttled up to between 1/4 and 1/3 throttle and the machine seemed to keep running. Throttling up to /12, though, and it ran for a few minutes and began to stall. _____ I have not tested the flow out of the pump when running nor have I replaced the hose between the pump and carb. However, it does not make sense that blockage there would cause this problem, since the pump will empty the filter straightaway. Still, I guess that I can do that or even switch back to the mechanical pump (that likely never was a problem - I learned after adding the electric pump last year that my problem then was a dirty carb).
The guys are right, start at one end and follow the connections till you find the blockage. I had a tractor with similar trouble, replaced everything carb and all and found a large butterfly in the tank that would on occasion block the outlet. Check that tank outlet first to make sure it will flow a couple gallons without slowing down.
I've pretty much done that. I've replaced all fuel hoses and checked the flow by attaching a length of fuel hose to each hard component. Over the weekend, I attached that hose to the output of the filter and appears to flow well, perhaps a bit less than ahead of the filter but not significantly less (as one would expect). I attached the hose to the output side of the pump and ran that and, again, fuel seems to flow well. _____ Put the whole works back together and same issue: runs fine at idle and up to about 1/4 throttle; speed up to 1/2+ and after 5 minutes it's starved for fuel. Moving, standing still, no matter, exact same behavior. I can't imagine that there could be anything in the tank that would restrict flow at the outlet only when the engine is running that would not also restrict flow when the system is merely draining. _____ Out of desperation, I am thinking of reverting back to the mechanical fuel pump which is still mounted (it and the shut off valve are the only in-line components not yet replaced). If that doesn't work, I suppose I'll have to pull the tank (not looking froward to removing the rops without the right equipment). _____ Stupid skidloader (or skidloader owner, maybe). Argh!
Well, it's bobcat 2, idiot owner/operator zero. I switched back to the mechanical fuel pump and she runs like a top. Once again, what appears to me to be ain't. What really hurts, is the fact that the electric pump was only in there because it "appeared" that the mechanical pump was shot - not so, It just needed the carb cleaned out again. _____ Thanks, fellows, for your input. Until next time (and I am certain there will be a next time...sigh), happy skiddin'!
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Glad to hear you got it working. I wonder if your electric fuel pump is busted not letting any gas through?
