Bulletin: SVB-111

Date Issued: February 15, 2005

Category: Procedural

Subject: Periodic cleaning of the Hydraulic Power Unit (HPU) oil coolers

Machine Models: LOADMASTER III Hydraulic Loaders

Back to Index
 

Problem

Recommended Action

Problem:

Proper operation of the hydraulic power unit on the LOADMASTER depends on the ability of the oil cooler to transfer heat loads from the hydraulic system during normal operation. If the oil cooler becomes clogged with dust and debris, the cooling performance of the hydraulic system can be reduced and possibly lead to protective shutdowns due to high oil temperature. 

The cleanliness and condition of the HPU oil cooler may be neglected on the LOADMASTER III units since the oil cooler is positioned on top of the loader and behind the HPU shroud assembly where visual access is either restricted or somewhat awkward to perform. As such, customers may not be aware that the oil cooler needs periodic attention to maintain optimum performance.

Back to top

Recommended action:

Alliance Machine Systems International, LLC recommends operators add the following cleaning procedure to your preventative maintenance program for the LOADMASTER. We recommend that cleaning using compressed air be accomplished at weekly intervals

This procedure will be included into LOADMASTER maintenance manuals for new machines.

Always follow proper safety procedures when working on a machine.  If you are unsure about anything in the procedure, contact your supervisor or Alliance Customer Service at 888-762-2200, option 2 for assistance.

Back to top

Clean dust from hydraulic power unit cooling fan

Dust buildup reduces the effectiveness of the cooling fan on the hydraulic power unit, increasing the likelihood of overheating. Once a week, turn off the hydraulic power unit and blow compressed air through the cooling fins to remove dust. Wear safety glasses and use an air gun regulated at 30 psi.

For best cooling performance make sure that the three adjustable exhaust louvers on the oil cooler are always set to the full open position.

To perform an initial inspection of the oil cooler to determine if any dust buildup exists, use a flashlight looking through the fan assembly to inspect the cooling fins on the inside of the cooler for any buildup.

If there is already an accumulation of dust that cannot be removed by using compressed air alone, remove the fan assembly and clean out as follows:

1. Lock out the machine according the instructions in your operator manual.
2. Remove the bolts to the fan cover.
3. Remove the motor mount bolts and remove the fan assembly from the hydraulic power unit.
4. Vacuum the dust from the inside of the cooling unit.
5. Replace the fan assembly and fan cover.
6. Remove the lockout and resume operation.

Back to top

Back to Index