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HAVE A 2011 GXU 613 MACK MP8 ENGINE FUEL LEAK DOWN OVERNIGHT…

HAVE A 2011 GXU 613...
HAVE A 2011 GXU 613 MACK MP8 ENGINE FUEL LEAK DOWN OVERNIGHT REPLACED FILTER BASE TRYING TO FIND OUT IF FUEL SHOULD COME OUT OF RETURN FUEL LINE WHILE PRIMING FILTERS THE PRIMER VALVE WAS LEAKING FUEL IS THE REASON I REPLACED IT IT WILL NOT REGEN NO CODES
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Answered in 13 minutes by:
3/11/2019
Technician: Mike Mcmillan, Shop Foreman/Triage Tech replied 3 years ago
Mike Mcmillan
Mike Mcmillan, Shop Foreman/Triage Tech
Category: Medium and Heavy Trucks
Satisfied Customers: 6,472
Experience: Volvo/Mack Master Tech, Certified with Cummins, Eaton, GM, Hino, Detroit Diesel
Verified
Hello and thank you for using Just Answer. My name isSteve. I will be assisting you with your issue. Have you checked the overflow valve on this?
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Customer reply replied 3 years ago
no
Technician: Mike Mcmillan, Shop Foreman/Triage Tech replied 3 years ago

Okay, I would inspect the over flow valve. This is located at the very front of the head. It takes a 7/8 wrench to remove. This is the check valve in the fuel system. There is 2 other non-serviceable valves in the filter housing but since that is new I am sure they are fine. You should only get fuel out of the return while the engine is running and not while priming. There will be a very small amount. Check the spring pressure on that overflow valve and make sure there is no debris and that the side of the valve inside is not scored up. Also when the unit is running check inside the fuel tanks for any signs of air in the return. There should only be micro sized bubbles. Any larger is a sign of either it sucking air or injector cups leaking. Please let me know if you have any further questions on this. It will be my pleasure to help anyway I can. Thank you.

Mike Mcmillan
Mike Mcmillan, Shop Foreman/Triage Tech
Category: Medium and Heavy Trucks
Satisfied Customers: 6,472
Experience: Volvo/Mack Master Tech, Certified with Cummins, Eaton, GM, Hino, Detroit Diesel
Verified
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Mike Mcmillan
Mike Mcmillan
Mike Mcmillan, Shop Foreman/Triage Tech
Category: Medium and Heavy Trucks
Satisfied Customers: 6,472
6,472 Satisfied Customers
Experience: Volvo/Mack Master Tech, Certified with Cummins, Eaton, GM, Hino, Detroit Diesel

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