1991 580 Sk with CAV pump.The engine is hunting at a certain RPM,just off idel. Also does these pumps have a govenor ,if it does I don't think mine is working. Any thoughts or knowlege much appreciated...................Sam
Yes, it does have a governor built in to the pump, but to adjust it is a bit technical. Do the simple things first - 1) are fuel filters clean & is there a good supply of fuel to them? - no restrictions 2) is air filter clean? 3) are the engine mounts in good order. If they are not, the engine will move around quite alot at certain RPMS. 4) is there any hydraulic load on the pump? A sticky control lever may be causing some load, affecting the idle.
Thanks for the reply alrman...yes all is good..I have seen this on other equipment in the past also.It hunts just off idle in nutral or in gear.It idles fine and smooth after 1000 rpm. Also I think it doesn't have the power it should.No grunt.
You should carry out a stall test. This may tell you if you have an engine power problem to worry about or not. Apply the brakes & 4th gear, & watch engine RPM under different loads at full revs No Load - 2350 - 2450 Rpm Hyd stall - 2230 - 2330 Rpm (cycle loader to max crowd & hold under load) Trans stall - 2100 - 2200 Rpm (engage fwd & apply max revs) Combined - approx. 1500 Rpm minimum (hyd & transmission together - there is no spec - it's an educated guess)