Mohawk A-7, Manual

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MOHAWK MODEL A-7
17
TROUBLE SHOOTING
WARNING: NEVER ATTEMPT TO LOOSEN HYDRAULIC FITTINGS, OR OVERRIDE SAFETY DEVICES IN AN
ATTEMPT TO CORRECT A PROBLEM. ALL TESTS ARE TO BE PERFORMED WITH NO VEHICLE.
HYDRAULIC SAFETY CHECK
NOTE: THE HYDRAULIC SAFETY CHECK IS TO BE PERFORMED WITH NO VEHICLE ON THE UNIT.
CONTACT YOUR LOCAL MOHAWK DISTRIBUTOR OR THE MOHAWK FACTORY IF EITHER TEST FAILS.
MAINSIDE SAFETY CHECK:
1. RAISE THE UNIT APPROXIMATELY 3 FEET
2. DISENGAGE THE OFFSIDE MECHANICAL SAFETY
3. LOWER THE UNIT ONTO THE MAINSIDE MECHANICAL
SAFETY
4. WHILE CONTINUING TO HOLD DOWN THE POWER UNIT
LOWERING HANDLE, OBSERVE THE
OFFSIDE
CARRIAGE FOR MOVEMENT. THE UNIT HAS CHECK
OUT OK IF THERE IS NO MOVEMENT (
OFFSIDE
CARRIAGE DOES NOT CONTINUE TO LOWER)
OFFSIDE SAFETY CHECK:
1. RAISE THE UNIT APPROXIMATELY 3 FEET
2. DISENGAGE THE MAINSIDE MECHANICAL SAFETY
3. LOWER THE UNIT ONTO THE OFFSIDE MECHANICAL
SAFETY
4. WHILE CONTINUING TO HOLD DOWN THE POWER UNIT
LOWERING HANDLE, OBSERVE THE
MAINSIDE
CARRIAGE FOR MOVEMENT. THE UNIT HAS CHECK
OUT OK IF THERE IS NO MOVEMENT (
MAINSIDE
CARRIAGE DOES NOT CONTINUE TO LOWER)
POSSIBLE CAUSE SOLUTION
NOT RAISING LOAD
LOW HYDRAULIC FLUID LEVEL LOWER UNIT. REMOVE RESERVOIR BREATHER CAP. FILL UNIT TO WITHIN 1/2
INCH BELOW PORT. USE DEXRON III TRANSMISSION / HYDRAULIC FLUID.
PRESSURE RELIEF ADJUSTMENT CONTACT MOHAWK SERVICE DEPARTMENT.
PRESSURE RELIEF CONTAMINATION REFER TO POWER UNIT SPECIFICATIONS. REMOVE AND CLEAN DEBRIS FROM
VALVE ASSEMBLY. SEE FIGURE 13.
VOLTAGE TO POWER UNIT REFER TO POWER UNIT SPECIFICATIONS. CONSULT AN ELECTRICIAN
UNIT OVERLOADED VEHICLE IS TO HEAVY TO BE RAISED
NOT LOWERING
MECHANICAL LOCKS ENGAGED RAISE UNIT. DISENGAGE MECHANICAL LOCKS.
UNIT UNEVEN (SIDE TO SIDE) RAISE UNIT TO FULL HEIGHT TO EQUALIZE. THEN LOWER
OR
USE DIVERTER VALVE TO EQUALIZE
POSTS OUT OF SQUARE VERIFY LEVEL ASSEMBLY. MAKE ANY AND ALL NECESSARY ADJUSTMENTS.
SEE FIGURE 7 & 8.
DEBRIS IN POSTS (TOOLS ETC.) CLEAN UNIT
OBSTRUCTION UNDER VEHICLE OR LIFT REMOVE OBSTRUCTION.
RAISING UNEVEN
RULE OF THUMB:
IF THE MAIN SIDE IS HIGH, RUN UNIT TO FULL HEIGHT. IF THE MAIN SIDE IS LOW, LOWER UNIT TO
FLOOR. ALLOW TIME FOR THE OFF SIDE TO EQUALIZE.
AIR IN SYSTEM BLEED UNIT. REFER TO BLEEDING PROCEDURES.
CARRIAGE BEARINGS CONTACTING CARRIAGE
STOPS CARRIAGE BEARINGS ON THE MAIN SIDE MUST NOT CONTACT CARRIAGE
STOPS. (RESULT OF INCORRECT CYLINDER SHIMS.) SEE
“ SHIMMING FOR
CHAIN TENSION” SECTION. SEE FIGURE 9.
POSTS OUT OF SQUARE VERIFY LEVEL ASSEMBLY. MAKE ANY AND ALL NECESSARY ADJUSTMENTS.
SEE FIGURE 7 & 8..
CYLINDER SHIMS VERIFY CYLINDER SHIMS. MAKE ANY AND ALL NECESSARY ADJUSTMENTS.
SEE
“ SHIMMING FOR CHAIN TENSION” SECTION. SEE FIGURE 9.
SHOP FLOOR UNEVEN VERIFY PROPER INSTALLATION OF MAIN SIDE POST. MAIN SIDE TO BE ON
HIGH SIDE. SEE FIGURE 11.