Hi - My 743 is having a fuel starvation problem. Symptoms: machine will start almost start and then die or the machine will run for a period then die. I read one of the post that was submitted for a 743B relating to a fuel problem and it had several great suggestions, but I would like to know if the 743 has any other unique issues. First, the symptom that has me most concerned is that normally the primer ball is hard after I prime, but I really can't get the ball to fill with fuel. Isn't the normal state that when you prime with the ball that the ball should be at least firm? Anyone have any suggestions?
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mllud
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I cant abswer about the particulars about a 743 but some things are common problems. I own a N/H. It sounds like you have an air leak in the fuel line from the primer bolb back to the pickup tube inside the tank.Im sure you have plenty of fuel.
The pickup tubes on bobcats are known to rot off. the primer bulb could be bad also.It has a check valve that only allows fuel to be sucked but not drain back into the tank. I would start with the primer bulb and work back all the way to the tank. A 743 uner could know sonething else thats specefic to that machine
Mike
The pickup tubes on bobcats are known to rot off. the primer bulb could be bad also.It has a check valve that only allows fuel to be sucked but not drain back into the tank. I would start with the primer bulb and work back all the way to the tank. A 743 uner could know sonething else thats specefic to that machine
Mike
mllud
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I need to start putting on my glasses to check my spelling. The pick up tube is inside the tank. I didnt explain that.
I would start by lifting the cab, remove the puckup line from the top of the tank and ensure the puckup tube is not broken off or cracked. At the end there should be a filter with a one way valve at the end. This assists in priming as when you squeeze the primer bulb you need to prevent the fuel from being pushed back to the tank, this is especially true for old primber bulbs that don't seal up rite. You are opening the bleed screw on the injector pump? ensure you close it when you have primed it or it will start then simply die.
When you are priming it with the bleed screw open, the primer bulb should feel firm and a constant pressure as you squeeze, no air noises as it flows through the valve and back to the fuel tank. Its sort of a feel thing, you can feel the air bubbles in the lines, har to explain. When you have a good prime close the valve and you shoudl be set.
A blocked puckup tube filter will make you loose prime and the primer bulb will flatten out.
See how you go with that, its easier to show and explain. The fuel system in these engines is really very simple.
Thanks for the replies. I did work from the bulb back to the tank and checked the line but I didn't realize that there was pickup tube filter. Is the filter at the end of the hose in the tank? Is there a special technique that you use to remove the tube from the tank to check the filter. Again, thanks for the help and you guys are the best!!!!!!!!!!!!
a door panel removal tool which looks like a wide screw driver with a vee cut in te end works well for prying out the rubber bushing that secures the 90 degree fitting which holds the pickup tube , if the pck up tube is ok it could be the filter seals as that glass bowled filter has always caused problems for me , I have put adaptors on that filter head to covert to spin on and have changed quite a few of the heads to newer style spin on filters , sometimes the primer bulb gets clogged up in the check ball on the tank side the bulb
Even using a screw driver works, i found re-installation can be a little tricky but found a small flat blade screw driver works pretty well. Some times its a bit hard, but take you time and be patient, you'll get there.
