JD 750 blew smoke now continual high RPM's

[smalson]

I have a JD 750. It has run well for the couple hundred hours I've had it. It is now around 1850 hours. This week the right idiot light came on. I believe it is the temperature light. I checked the coolant, and it was fine. While I was checking her over, I also changed the oil and filter. Figured it was time.

After the oil change (JD oil & filter) and checking the coolant, I started it up to do a couple small jobs. Ran well, as usual, although the warning light was still on. As I was changing implements, I let it idle.

There seemed to be an odd sound ... just a little rattle.

Within about 15 seconds, it began to smoke more than I've ever seen. It coughed, sputtered, and spit smoke for about 15 seconds . . . then the RPMs increased and it began to run really smooth . . . but fast. I pulled back the throttle, but there was no change. The RPMs were above the gauge range until I pulled back to the point it died. There was no middle range . . . either over-revving or stopped.

HELP!!!

What happened and what do I need to do?

Steve Malson
Mason, MI

 

[kuboman]

I have a JD 750. It has run well for the couple hundred hours I've had it. It is now around 1850 hours. This week the right idiot light came on. I believe it is the temperature light. I checked the coolant, and it was fine. While I was checking her over, I also changed the oil and filter. Figured it was time.

After the oil change (JD oil & filter) and checking the coolant, I started it up to do a couple small jobs. Ran well, as usual, although the warning light was still on. As I was changing implements, I let it idle.

There seemed to be an odd sound ... just a little rattle.

Within about 15 seconds, it began to smoke more than I've ever seen. It coughed, sputtered, and spit smoke for about 15 seconds . . . then the RPMs increased and it began to run really smooth . . . but fast. I pulled back the throttle, but there was no change. The RPMs were above the gauge range until I pulled back to the point it died. There was no middle range . . . either over-revving or stopped.

HELP!!!

What happened and what do I need to do?

Steve Malson
Mason, MI

Sounds like something in the IP fell apart, governor or something.:thumbdown:

 

[smalson]

IP???

Not sure what you mean by that.

 

[whistlepig]

Injection pump. Sounds like the motor is getting fuel dumped in to it. Diesel fuel or crankcase oil. It will burn both.

 

[smalson]

I'll have to check on that. I've never dealt with that aspect of an engine. Thanks.
Steve

 

[kuboman]

IP???

Not sure what you mean by that.

Sorry....Injection Pump.

 

[Gary Fowler]

Sounds like the injection pump run away. I am a little concerned with the idiot lite that "I think is the temperature". Are you sure this is the temp lite, not low oil pressure lite. Either way, better get to the bottom of that and verify what it actually is. But you for sure are going to need to remove the injection pump and have it rebuilt. Luckily you could still stop it, my Dad had one run away with him on a D17 AC and it wouldnt shut down, had to turn off the fuel valve under the tank while trying to hold on with the tractor doing about 15 MPH across the field with it in 3 gear with a 4 row disc behind it.

 

[JD755]

Sounds like the injection pump run away. I am a little concerned with the idiot lite that "I think is the temperature". Are you sure this is the temp lite, not low oil pressure lite.

The right side light is in fact the oil pressure light.

 

[Brimstone10x]

I would say more likely its the governor . and better get a real gauge on that oil psi before you do any more work with it. it dont sound good.

 

[beenthere]

........................, my Dad had one run away with him on a D17 AC and it wouldnt shut down, had to turn off the fuel valve under the tank while trying to hold on with the tractor doing about 15 MPH across the field with it in 3 gear with a 4 row disc behind it.

Really??????????