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Curtis B.
Curtis B., Technician
Category: Construction and Road Equipment
Satisfied Customers: 1207
Experience:  Technican turned service manager with multiple lines of equipment and rental units.
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Caterpillar 931 - motor # ***** problem=starts promptly-runs1-2

Customer Question

caterpillar 931 B- motor # ***** problem=starts promptly-runs1-2 hrs then suddenly stops- can restart immediately and again will run 0.5 hrs and stops again. I have changed fuel filters,blown lines out from tank to primary pump. Help!
Submitted: 2 years ago.
Category: Construction and Road Equipment
Expert:  catmastertech replied 2 years ago.
Hello, I am sorry no one could help you earlier, I hope this is not too late to be helpful.Check your return line fitting for a plugged orifice. Excessive pressure in the fuel system will cause it to shutoff.Also, take pressure reading from the fuel system. It should have 30 - 40 psi at high idle and not below 10 at idle. Let me know what you find and if you need more help. Please post the machine serial number if you do need further help.