Oil & Fuel John Deere 755 won't throttle up

[paulkennedypaul]

Hello. I was wondering if some one could help me with a problem I have with my John Deere 755, I blew a head gasket, I could tell this by the bubbles in the radiator. so I removed the head and had .005 in taken off to flatten the head. I reinstalled every thing, bled the system ,got it running but it won't throttle up and black smoke pours out the pipe all the time, some times it goes white then quits. could some one please help. I am ripping my hair out. Thank very much

 

[kennyd]

Welcome to TBN

Did you move (or remove) the injector pump at all? It sounds like the timing may be off-and that is set by the IP.

 

[paulkennedypaul]

Thanks, no I never took any of the pump apart, olny removed the cylinder head.

 

[jd110]

Check the fuel return line. Make sure it is properly connected and there are no restrictions or kinks.

 

[jbarker855]

During tear-down, did you find a failure site in head gasket? Did you closely inspect head? It is possible that cylinder head is cracked, and that is why you had bubbles in coolant. You may still have a bad cylinder head on machine. Check radiator again to be sure you don't have the same symptoms you did before head gasket repair. Good luck with this.
-Jay

 

[Kevin M]

Do you hear the electric lift fuel pump running when you turn the key on ? I had similar symptons on my 755 ,@ 5 or 600 hours the lift pump went. Plus the screen in the tank was plugged with trash , something to check anyway !

 

[paulkennedypaul]

Thanks for the support. I will try to answer all the questions, the head gasket showed signs of leaking and the head was maged. with no cracks. the return fuel line seams to be free of obstruction, this was replaced with all new line.the screen in the tank was removed and cleaned. I can hear the electric fuel pump running, It seam to be getting fuel, I think or guess maybe the injectors may be no good ? but it did run before.

 

[Kevin M]

How many hours are on your tractor ? I assuming you have a nice clean fuel filter in it too ?

 

[paulkennedypaul]

I have around 1300 hours on the 755. I did drain the tank and refiled with new off road diesel fuel after cleaning the screen that was laying in the bottom of the tank. I did just take the injectors out and took them to Northern Diesel, Steve checked and said two were not spraying very well. he said he could rebuild them for $70 dollars an injector, I told him to do it, I hope this is it. I have done almost every thing else.