John Deere 6620 won't stay running

I am going to post here as well as on the John Deere site for hopefully quicker action and basically this is an engine issue rather than a combine problem. I wanted to move my Deere 6620 to another farm so I could make repairs on the rear axle last week. It will start but only run for 3 or 4 minutes. Then you open the air bleeder bolt on the fuel filters and pump the plunger on the injection pump removing all of the air and filling the filters and it will start and run another 3 or 4 minutes. Did that process a couple of times and still get the same 3 or 4 minutes of run time before it starts missing, looses rpm and dies. Was running perfect when I quit using it in the field three four weeks ago. Fuel filters would have around 75 hours on them. Electric pump on tank has never caused problems and you can hear it work. Tried to run it last week on Saturday when it was 40 degrees, same problem. Engine compartment may not have warmed up to 40 degrees. Does have 10% biodiesel in the tank. Do I have some frozen water in the filters?? Would the filters plug in 75 hours?? If the filters were plugged or iced would doing the plunger on the injection pump actually solve plugged fuel filters?? I did drain the water trap on the fuel tank and only diesel came out. Screen in the sediment bulb on the tank is clean. I have full flow from the sediment bulb out the bottom of the tank. Do I have some chaff floating up and down in the fuel line from the tank?? Wanted to get it moved before winter really sets in. Any ideas?? Thanks.

Have you checked the electric pump to make sure it's pumping up to the pump on the injection pump? It might be making noise, but is it moving fuel?

Take a 5/8ths wrench and remove the fuel line between the sediment bowl and the electric pump.
If you do not get a FULL (again, FULL) stream of fuel out, your problem is a plugged stand pipe or the filter screen in the sediment bowl.

This happened to me on my 6620 (stand pipe) and yesterday on my brother's 6600 (screen/strainer in sediment bowl plugged) He has algae in his tank which looks very black in the screen. Algae grows at the boundary of fuel and water in the tank.
I knew something was wrong when I had to ether (gasp! for those who think ether is bad) the 6600 to get it to run. The strainer was plugged.

It is doubtful that it was ice at 40 degrees since water melts at 32.

Does your engine have a rotary or inline inj pump? If it hs a rotary pump loosen both screws on inj pump timing widow,pry rubber gasket loose then see if engine will run longer than 4 minutes.

The 6620 has the inline Bosch not the Roosamaster. If the combine is not gear drive, the engine is turboed and is a direct drop-in for a 4440 tractor.

(quoted from post at 13:17:17 12/01/14) The 6620 has the inline Bosch not the Roosamaster. If the combine is not gear drive, the engine is turboed and is a direct drop-in for a 4440 tractor.

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JD parts catalog #1666 shows 6620 could have either rotary or inline fuel inj pump.

You are correct. I believe the rotary was used for the gear drive combine, not the hydro as it was lower horsepower.

I did work with the combine some this afternoon. Pretty cold today so I will crank it tomorrow when it is subpose to be 35 degrees. I took the sediment bulb off of the inline injector pump and checked the screen. Looked good. While I had the bulb off I turned the switch on and the pump pushed a good amount of fuel out with the sediment bulb off. So, I think that end is OK. Bought new fuel filters today and put them on. Bled the air out with the bleeder screw and plunger. Checked with my fuel supplier and the last fuel I got had the winterizer products in it. So, tomorrow when it warms up some I will crank it up and see what happens. If I continue to have problems I will check for sustained flow from the fuel tank. Thanks for the ideas.

Agree with MikeJM. Had the exact same thing happen to my 4400.