450j sputters at start up

I have a 2005 John Deere 450J with around 5500hrs on it. When you first start it in the morning. It seem to idle fine but once you throttle up a bit it begins to sputter. The sputtering takes around 15 second or so to clear up. Then it runs great for the rest of the day.

It always starts perfectly fine. No excessive cranking.

Sounds like its getting air in the fuel lines somehow. I bet if you turn the key on and let the electric pump run for 30 or so seconds before you attempt to start, it won't sputter. I have a tractor that was doing this exact same thing. Got progressively worse over time, to the point that if I didn't run the electric pump, I would have to bleed the injectors before it would start. I put an inline backflow valve in the fuel line coming into the primary filter and it fixed it.

swampman said:

Sounds like its getting air in the fuel lines somehow. I bet if you turn the key on and let the electric pump run for 30 or so seconds before you attempt to start, it won't sputter. I have a tractor that was doing this exact same thing. Got progressively worse over time, to the point that if I didn't run the electric pump, I would have to bleed the injectors before it would start. I put an inline backflow valve in the fuel line coming into the primary filter and it fixed it.

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no electric pump on this machine. Anyone know if there is a back flow valve on this dozer that could have failed?

Canadian_digger said:

Anyone know if there is a back flow valve on this dozer that could have failed?

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No backflow check valves on that machine.

Well crap. Sounds like you are losing fuel pressure somehow. A check valve just before the primary filter would still be a cheap fix. Was not OEM on my tractor either, but sure fixed my very similar issues.

Also check all the grommets on the fuel supply side. Between the filters to the supply pump all the way to the injection pump

I have an M11 Cummins in a dump truck that starts great and then dies after 40 seconds. Check valve is good so must have a tiny air leak somewhere. If I hold the throttle at about 1200 RPM it will usually pull enough fuel to keep running. Once I get past the initial dyeing it runs great and I can shut it off and start it back up no problem as long as it doesn't sit for more than a few hours. I even put what is supposed to be a fuel filter that solves the dying problem. It doesn't. It's not bad enough and there are no fuel leaks so I'm not overly concerned about it. It's just frustrating, especially if the batteries are low and I need to boost it for the 2nd start that takes about 15 seconds to fill the filter. Thank god it's self priming or I'd have to spend a bunch to fix it.

Canadian_digger said:

I have a 2005 John Deere 450J with around 5500hrs on it. When you first start it in the morning. It seem to idle fine but once you throttle up a bit it begins to sputter. View attachment 260306 The sputtering takes around 15 second or so to clear up. Then it runs great for the rest of the day.

It always starts perfectly fine. No excessive cranking.

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Did you determine what was causing the issue? Mine is doing the same thing

Check your fuel cap for clogged check valves and clogged mesh screen it has 2 valves one for pressure and one for vacuum when remove to clean and free up do not swap locations.

Steve Austin said:

Check your fuel cap for clogged check valves and clogged mesh screen it has 2 valves one for pressure and one for vacuum when remove to clean and free up do not swap locations.

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That is a good tip for sure. Mine ended up being the injection pump. 7400 hours on the original