INSTRUCTION MANUAL:
Model Series: MHP100 –MHP1000 inclusive
Hi-Force Limited – Prospect Way – Daventry – Northants NN11 8PL – United Kingdom
Tel: +44(0) 1327 301000: Fax: +44(0) 1327 706555: Website: www.hi-force.com
The operating lever must be stationary during
any pressure changeover.
Ensure fluid level in the reservoir does not drop
below minimum operating level. Air may be
pumped into the system if this occurs. Never
jerk the handle during use as this makes the
pump inefficient and can cause unexpected
pressure range change over. A smooth steady
action gives best results.
Each pump is fitted with an adjustable pressure
relief valve. This valve is set at the factory to the
maximum working pressure of the pump model
specified. This valve can be customer adjusted
to any desired pressure within the rating of the
pump. Details for the method of adjustment for
this valve are available on request.
2. Pressure is released by turning the Pressure
Release Valve anti-clockwise.
3. Never stand in a direct line with the
application of force or allow personnel under
loads that are not securely supported by
mechanical means.
After Operation:
1. Fully return hydraulic fluid to pump. Check
hydraulic fluid level in reservoir to prevent over
filling of the tank.
2. Keep hydraulic fluid clean. Change as
necessary and frequently if using water.
3. After heavy use, it may be necessary to
clean the filter. Before removing the filter
element from the pump, ensure that the system
is depressurised. Unscrew the filter retainer
screw shown on the pump diagram above.
Remove the filter, clean and replace.
4. It is advisable that if the system has been
used on water and the unit is to be stored for a
period of time, that the system is drained and
the pump unit flushed through prior to storage.
Troubleshooting:
No delivery:
Pump handle when operated does not
operate plunger. Incorrect assembly.
Suction valves not sealing. Remove
contaminant or replace the seals.
Relief valve seal sticking or
contaminant not enabling it to seal.
Seal failure on delivery valve
Handle drops on its own:
Suction ball is not sealing completely.
With the release valve open pump fluid
around the pump, this may dislodge
the dirt. Failing this, remove and
clean/replace both high and low
pressure suction balls
Handle rises when left:
Delivery valve is not sealing correctly.
With the release valve open pump fluid
around the pump, this may dislodge
the dirt. If this does not work remove
the optional pressure gauge if fitted or
the bolt which is in the outlet port on
the top of the pump, remove outlet
seal spacer, spring and outlet seal.
Inspect o-ring on seal and replace if
damaged. Also check the sealing face
on the pump body for damage or dirt.
Trapped air in the pump
Air in the pump will cause loss of
effective pumping stroke and will also
permit high pressure to be raised even
when the pressure selection button is in
the low pressure position.
Some possible areas where air is being
drawn into the pump are:-
1.
Release valve joint washer
2.
Release valve spindle seal
3.
The suction pipe connection
4.
Low/High Pressure changeover
valve
Under normal circumstances should any of the
above cause air to be drawn into the pump
unit it will be visible by the leakage of the fluid
medium from that area.
Service & Maintenance:
Only genuine Hi-Force spare parts should be
used in the repair or servicing of these units.
We recommend that any servicing or repair of
this equipment is only carried out by an
authorised Hi-Force repair centre.
