Oil & Fuel Ty 290 only runs full rpm

[SHANE6666]

Quick question if there ever was one
I have a ty290 engine it run full rpm only. No throttle control
Doesn't over rpm. Any common known causes on this particular engine
That causes this? Or just tear down inj pump looking for bad seal or oring where fuel is bypassing?
Exhaust is very clean. Tractor is new but sat for a long time
Replaced bad fuel flushed lines and it was doing this prior to sitting
It sat because of the issue it has now

Thanks in advance

 

[RonMar]

Sounds like a stuck governor cup. The IP drive rotates the pump and also spins the governor assembly. The governor consists of a spinning spoke assembly that rotates ball bearings which act as flyweights. As the ball bearings spin they push outward against a cone shaped cup. The faster they spin(higher RPM), the more the cup moves. the cup is connected to the fuel rack and the faster/farther the balls spin outward, the more the fuel rack closes. The throttle assembly pushes against a spring which presses against the cup forcing the balls back inward and opening the throttle. So the throttle/spring force is trying to increase RPM and the governor flyweights are trying to decrease RPM. There is a given RPM where the ball bearing centrifugal force = the combined throttle and spring force to run at a commanded RPM. SO if it is stuck at high RPM, the governor cup is probably stuck, preventing the balls from moving the cup and reducing the RPM. This is also a likley scenario as this is where the cup sets when the engine isn't running to provide flyweight force to counter the spring... It may simply be corroded... Does it maintain this high RPM with load changes? If it does, it still has some available travel...

 

[SHANE6666]

Sounds like a stuck governor cup. The IP drive rotates the pump and also spins the governor assembly. The governor consists of a spinning spoke assembly that rotates ball bearings which act as flyweights. As the ball bearings spin they push outward against a cone shaped cup. The faster they spin(higher RPM), the more the cup moves. the cup is connected to the fuel rack and the faster/farther the balls spin outward, the more the fuel rack closes. The throttle assembly pushes against a spring which presses against the cup forcing the balls back inward and opening the throttle. So the throttle/spring force is trying to increase RPM and the governor flyweights are trying to decrease RPM. There is a given RPM where the ball bearing centrifugal force = the combined throttle and spring force to run at a commanded RPM. SO if it is stuck at high RPM, the governor cup is probably stuck, preventing the balls from moving the cup and reducing the RPM. This is also a likley scenario as this is where the cup sets when the engine isn't running to provide flyweight force to counter the spring... It may simply be corroded... Does it maintain this high RPM with load changes? If it does, it still has some available travel...

I think I found the issue. Yes governor issue. It seems the governor is in the pump
I found that the pump has its own oil supply.
I pulled the dip stick and it's all gummy and smells like the bad fuel that was in it.
I will drain and fill with something to loosen it and flush then fill with new oil and see what happens.

Thank you for your informative reply .

 

[RonMar]

Yep, governor is in the rear side of the Injector Pump housing. Kerosene is usually good for flushing. I use air compressor oil in my IP oil sump... Gunk in the sump might interfere with operation, but I would think it would make it opperate erratically, not stick at high RPM. If it set for a while, the top parts of the assembly that were not in the oil may have corroded, so you may still need to disassemble the governor and make sure all the parts move freely...

 

[SHANE6666]

I should be able to remove back cover with no issues other than possible gasket damage.
There's nothing connected to cover that will effect governor directly correct
I pre soaked with wd-40 over night will drain and pull cover to visually inspect all parts.

 

[RonMar]

You should be able to pull the rear section to expose the linkages, the next section, the round part, is where the governor flyweights rotate, and the forward section is where the actual injector pump(pistons and cams) are located(has high pressure injector lines attached to the top). Here is a link to a thread discussing the IP and governor. Not sure if it is the same pump as on your engine though. It has some links to pics of disassembled IP/governor assemblies that may give you an idea how things interact...

Good luck.

http://www.tractorbynet.com/forums/...hrottle-4.html?highlight=governor+disassemble

 

[SPIKER]

Note also check the linkage where the throttle gos into the pump or even below the dash etc for bent, stuck sticks or stuck rotating arm. Dont forget the hand throttle my be pushed forward (some people only use foot throttle.)

Mark

 

[SHANE6666]

You should be able to pull the rear section to expose the linkages, the next section, the round part, is where the governor flyweights rotate, and the forward section is where the actual injector pump(pistons and cams) are located(has high pressure injector lines attached to the top). Here is a link to a thread discussing the IP and governor. Not sure if it is the same pump as on your engine though. It has some links to pics of disassembled IP/governor assemblies that may give you an idea how things interact...

Good luck.

http://www.tractorbynet.com/forums/...hrottle-4.html?highlight=governor+disassemble

Problem resolve running great.
Found number two inj pump rack stuck wide open and number two pump not pumping. This was keeping number one supplying fuel at all times. Pulled pumps cleaned and cleaned inside pump housing
Replaced oil and working great. Thank for the info and help