Buhler FK348 User Manual

Page 14

Commercial Snowblower

START UP

HYDRAULIC CONTROL BLOCK

NON-STALLING-FAN FEATURE:

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) (page 16) 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) (page 16) 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 (#4) (page 16) 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.