Commercial Snowblower
HYDRAULIC CONTROL BLOCK
The Hydraulic Snowblower has a unique modulating element that keeps the blower fan from stalling in an overloaded condition. This is accomplished by starving the hydraulic flow to the front auger motor (which then stops feeding the fan) and diverts all of the flow (and energy) to the main fan motor. As the fan clears itself, and the pressure drops, the auger again begins feeding according to load. When the system is set up properly the fan motor should not stall or plug up.
MODULATING ELEMENT SETUP:
For optimum performance the modulating element (#4) (Fig. 1) must be adjusted to match the system pressure of the tractor being used. The factory setting is for a 2800- 3000 psi system. If your system is less, you should make adjustments accordingly. For adjustment:
Loosen the LOCK NUT (on the MODULATING VALVE (#4) and back off the adjusting screw till the screw turns freely by hand, and then turn it in till you feel the screw making contact with the pressure spring. One turn sets the pressure up by about 600 psi.
For 2100 psi turn the screw in 3 ½ turns.
For 2400 psi, turn in 4 turns
For 2700 psi, turn in 4 ½ turns
For 3000 psi, turn in 5 turns.
If the fan stalls (in an over load condition), the (#6) element is set too high. If the Auger slows and stops too soon, it is set too low. Once it is set it should not need to be adjusted any more.
Since there are a number of unknown variables that are unique to almost every situation, it is difficult to give an exact setting for a particular model. The variables are: hose size and length, type and size of quick couplers, etc.
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