# John Deere 5303 will not start



## Gcmcsandman (Jul 24, 2020)

Tractor was running fine. Stopped to put diesel in and when I took off the fuel cap I noticed that the tank had built up some type of negative pressure, so it sounded like I just popped the top on a coke. Now the tractor will not start. I have primed the fuel pump and their doesn't appear to be any air in the system but still not firing up. What next?


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## EdF (Sep 15, 2014)

Howdy Gcmcsandman, welcome to the tractor forum.

The vent in your fuel cap is plugged, which is what started your problem. Fix that first. 

In pulling a vacuum on the fuel tank, you have drawn air into the system somewhere. It won't run till you get the air out of the system. Does your engine have a lift pump (fuel pump)?? Check for ample fuel flow at the inlet to the lift pump and to the fuel filter. Bleed air out of the the fuel filter. Check flow at the inlet to the injection pump. 

Loosen all injection lines at the injectors and crank the engine till air is bled out of the lines. Crank for 15 second intervals and give your starter a rest to cool off. When you no longer see air bubbles in the fuel at the injectors, tighten the injection line connectors and you should be good to go.


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## Tx Jim (Jul 28, 2020)

Ditto fuel tank isn't venting which needs to be addressed/corrected. It's difficult to imagine if engine was operating then stopped that fuel tank vacuum created air in fuel system BUT stranger things has happened. I agree with Ed to check for air in filter & line to IP. I think it's a little premature to loosen injector lines but that may eventually have to be performed. Is fuel control solenoid on IP clicking when ign switch is turned to run position?


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