How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Curtis B. Your Own Question
Curtis B.
Curtis B., service manager
Category: Heavy Equipment
Satisfied Customers: 28057
Experience:  30 years exp. with diesel engines, heavy equipment and forklifts, including lp forklifts
Type Your Heavy Equipment Question Here...
Curtis B. is online now
A new question is answered every 9 seconds

bobcat: engine runs..rough..carb, flushed fuel fuel pump

This answer was rated:

I have a bobcat 632 unit has ford industrial 140. Problem engine runs until you get to rough ground, then engine will only run with choke out. I have removed and cleaned carb, flushed fuel system, installed new fuel pump and checked for spark. You can tell the engine acts like it is starving for fuel. Not sure where to go next.
Try a test line from the fuel pump inlet and dropped into the tank. Test will leave out all the suction side of the fuel system. If it runs as it should, you know it is a fuel suction problem and you can isolate each section , one at a time. If it doesn't help, I would think it is not a fuel problem but and electrical issue. Let me know. Thanks.
Customer: replied 7 years ago.

If you disconnect the inlet side of the pump, fuel runs out of the line with no restrictions, I have put a new electric pump on.


I put an inline spark tester with a .020 gap and it does not miss. I have also installed an new set of point set at .020".

Yes, it may run out with no restrictions, but it is not the same as driving the unit through the terrain. Again ,that will eliminate any question on the fuel supply. When you changed the points did you change the condenser?
Customer: replied 7 years ago.

I will try running a line from the pump to the tank fill and see what happens,


yes both points and cond

Good deal, let me know.
Customer: replied 7 years ago.
Found one bad spark plug and vent on fuel cap plugged, replaced plugs and cap.
Good job!!
Curtis B. and other Heavy Equipment Specialists are ready to help you