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I have d39e. Starts easy but seems to labor under heavy

load. Low power. I have...
i have d39e. Starts easy but seems to labor under heavy load. Low power. I have changed fuel filter and air filter. clean fuel. What next?
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Answered in 12 minutes by:
2/14/2016
Technician: Curtis B., Technician replied 6 years ago
Curtis B.
Curtis B., Technician
Category: Medium and Heavy Trucks
Satisfied Customers: 43,557
Experience: Technician turned service manager on multiple lines of trucks and engines, used in industry.
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Check the fule supply from the fuel tank, to the filter and to the primer pump. Or for test, make a test line from the primer pump inlet back into the fuel tank filler opening and run test for power. If power is good, then check fro restriction before the primer.

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Customer reply replied 6 years ago
I'm a little confused by the test.now i understand. Is there a way to measure fuel pressure?
Technician: Curtis B., Technician replied 6 years ago

You want to eliminate the suction system up to the primer pump, to see if there is any restriction. Fuel pressure would be something after the primer pump. Most low power problems are a lack of fuel from supply.

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Customer reply replied 6 years ago
got it
thank you
Technician: Curtis B., Technician replied 6 years ago

Thank you!

Curtis B.
Curtis B., Technician
Category: Medium and Heavy Trucks
Satisfied Customers: 43,557
Experience: Technician turned service manager on multiple lines of trucks and engines, used in industry.
Verified
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Satisfied Customers: 43,557
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