Bosch Injector pump.

[Red Rob]

I have an inline 6 injector pump from a Fiat allis crawler loader.
It starts & runs well BUT, it will not rev over 1500 rpm.
The throttle lever is only part way towards the stop screw, yet the govenor springs can be felt pushing back against me if I try to open the throttle any more. Also the engine speed starts to drop the harder I push the lever.
I have taken the govenor cover off the back of the pump & can see nothing bent or broken in there.
Any ideas?

 

[Anonymous-0]

Is this a robert bosch pump or american bosch. Robert Bosch pumps had a plate with four screws in the back that was full load delivery screw. There is a low idle screw also just above the serial plate on back. Were bad for the control rack to stick but usually that caused hard to start. Commonly on pumps with manual fuel pump shut-off cables, the cable will work out and as a result fuel flow is restricted and decrease in horsepower. Sorry can't be more help.

 

[Bob]

You will ALWAYS feel the increased tension of the governor springs fighting back as you "open the throttle".

Are you SURE you don't have a restriction in the fuel supply?

If not, I would get some professional help for the pump, BEFORE it sticks in the "max fuel" position.

Flying engine parts are REALLY ugly!

 

[guido]

Hello Red Bob.
It sounds to me that the governor spring is broken, the rack is sticking, or the adjusting mechanism is not keeping spring tension against the governor weights.
What you feel is the governor fly weights overcomming the governor spring tension.
When you adjust the no load speed you increase spring tension against the governor weights for higher R.P.M'S. Then the weights go agaist the spring tension, and the engine stops revving, and the governor is said to be in a state of balance.If you can to locate the governor spring assy you may see if it may have broken. The rack can be sticking and If you are not familiar with the pump, I would suggest you take the pump to a fuel shop.
Lots of parts in that pump.
Guido.