Hi guys,
This is my first time posting on the site. This may get a little long but I want to give you all the details up front.
Kubota F2680E mower
Year: 2010
Hours: 1993
Engine: D1105-ET03
Deck: 72"
2 wheel drive
I bought this machine a few weeks ago off of a local guy - had it listed on craigslist. He used it for his lawn care business. He said it would run but only at full throttle. He was told it simply needed a governor spring but he was afraid to tear into it and was not willing to spend any more $$ on it. He was asking $1200 - I offered $1000 because it is pretty clean and straight and the engine does start right up - runs smooth - just full throttle. He took my offer.
So here's the story on how it got to this point and what I've done so far. Last year he parked the machine at the end of the season with it running fine. This spring when he tried to start it up, it would not start. He talked to Kubota mechanic who said it was probably a stuck valve in the injection pump so he took the mower to some cheap, local outfit that supposedly rebuilt the pump. He said Kubota wanted more than he was willing to pay for the rebuild. After putting everything back together the engine starts and runs up to full throttle right away. A lot of back and forth between the guy and the local shop and other mechanics and they cannot figure out whats wrong with it and he does not push them to make it right and basically gives up on the thing. He was told by local Kubota mechanic that it sounds like the other shop forgot to connect or lost a governor spring. He said he was done with it.
I buy the machine and proceed to dig into it. My first time working on diesel engine but I grew up working with my dad working in an auto repair shop and repaired F-15s in the Air Force so I figured this would be a good place to take a gamble and jump into the deep end. I downloaded a service manual for the engine and have been comparing what I've found in it to what's on the machine in front of me. I pulled the throttle plate off and looked at the governor linkage - all springs are present and connected correctly. All levers move back and forth freely. The rack pin moves back and forth freely. The stop solenoid moves freely and I was told by the guy I bought this from that it was new. I can start the machine - it goes to full throttle regardless of the throttle position - I can shut down the engine with either the key or the stop lever so I don***8217;t believe I'm sucking oil from the case.
I go and talk to the Kubota mechanic at the local dealership and we go through the service manual together and verify that all the springs are in place so he says it sounds like the injection pump was not calibrated properly by the other shop when they put it back together. I remove the injection pump and take it to a reputable shop here in town and they rebuild it for me. They put new plungers in it, calibrate it and say they found nothing wrong with it but still take $316 - ouch. I put the rebuilt injection pump back in the engine with all the shims back in place, spring connected, etc and fire it up. Same problem - it starts right up and immediately goes to full throttle. I can modulate the rpms by moving the stop lever and essentially pushing the rack pin the opposite direction which leads me to believe the injection pump is working properly.
This is as far as I've gone with it. My thoughts are possibly frozen flyweights on the governor shaft from sitting all winter and the thing has not been run more than probably several minutes since last year. I found there is a port opening on the side of the engine case where the governor shaft is located. I removed the plug from that port and started up the engine and oil started to spurt out of it (small amount - not pressurized) so I can see that part of the shaft gets somewhat of an oil bath so I'm wondering if just letting the thing run for a while at full throttle would allow oil to work into the flyweight mechanism and work it loose if they are froze up. In order to remove the governor shaft I would have to pull the engine and remove the front cover. I don***8217;t really want to do that if I don***8217;t have to so I'm reaching out to you all looking for ideas, solutions, etc.
Sorry for such a long post but I think its necessary on this one. Thanks in advance for any feedback!!
PS - I dont have a service manual for the mower but plan on getting one asap.
This is my first time posting on the site. This may get a little long but I want to give you all the details up front.
Kubota F2680E mower
Year: 2010
Hours: 1993
Engine: D1105-ET03
Deck: 72"
2 wheel drive
I bought this machine a few weeks ago off of a local guy - had it listed on craigslist. He used it for his lawn care business. He said it would run but only at full throttle. He was told it simply needed a governor spring but he was afraid to tear into it and was not willing to spend any more $$ on it. He was asking $1200 - I offered $1000 because it is pretty clean and straight and the engine does start right up - runs smooth - just full throttle. He took my offer.
So here's the story on how it got to this point and what I've done so far. Last year he parked the machine at the end of the season with it running fine. This spring when he tried to start it up, it would not start. He talked to Kubota mechanic who said it was probably a stuck valve in the injection pump so he took the mower to some cheap, local outfit that supposedly rebuilt the pump. He said Kubota wanted more than he was willing to pay for the rebuild. After putting everything back together the engine starts and runs up to full throttle right away. A lot of back and forth between the guy and the local shop and other mechanics and they cannot figure out whats wrong with it and he does not push them to make it right and basically gives up on the thing. He was told by local Kubota mechanic that it sounds like the other shop forgot to connect or lost a governor spring. He said he was done with it.
I buy the machine and proceed to dig into it. My first time working on diesel engine but I grew up working with my dad working in an auto repair shop and repaired F-15s in the Air Force so I figured this would be a good place to take a gamble and jump into the deep end. I downloaded a service manual for the engine and have been comparing what I've found in it to what's on the machine in front of me. I pulled the throttle plate off and looked at the governor linkage - all springs are present and connected correctly. All levers move back and forth freely. The rack pin moves back and forth freely. The stop solenoid moves freely and I was told by the guy I bought this from that it was new. I can start the machine - it goes to full throttle regardless of the throttle position - I can shut down the engine with either the key or the stop lever so I don***8217;t believe I'm sucking oil from the case.
I go and talk to the Kubota mechanic at the local dealership and we go through the service manual together and verify that all the springs are in place so he says it sounds like the injection pump was not calibrated properly by the other shop when they put it back together. I remove the injection pump and take it to a reputable shop here in town and they rebuild it for me. They put new plungers in it, calibrate it and say they found nothing wrong with it but still take $316 - ouch. I put the rebuilt injection pump back in the engine with all the shims back in place, spring connected, etc and fire it up. Same problem - it starts right up and immediately goes to full throttle. I can modulate the rpms by moving the stop lever and essentially pushing the rack pin the opposite direction which leads me to believe the injection pump is working properly.
This is as far as I've gone with it. My thoughts are possibly frozen flyweights on the governor shaft from sitting all winter and the thing has not been run more than probably several minutes since last year. I found there is a port opening on the side of the engine case where the governor shaft is located. I removed the plug from that port and started up the engine and oil started to spurt out of it (small amount - not pressurized) so I can see that part of the shaft gets somewhat of an oil bath so I'm wondering if just letting the thing run for a while at full throttle would allow oil to work into the flyweight mechanism and work it loose if they are froze up. In order to remove the governor shaft I would have to pull the engine and remove the front cover. I don***8217;t really want to do that if I don***8217;t have to so I'm reaching out to you all looking for ideas, solutions, etc.
Sorry for such a long post but I think its necessary on this one. Thanks in advance for any feedback!!
PS - I dont have a service manual for the mower but plan on getting one asap.
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