Two post hydraulic lift HAPP 95
© 2013 HAPP Australia Pty Ltd
Version 9
Page
25
Using the same mechanism as for air bleeding the cylinders to release oil, equal oil volumes are required
for even lifting in the HAPP 90 and HAPP 95. A difference of 10ml will cause the lift to be uneven by
approximately 10mm.
There are a number of techniques available.
•
This is the recommended technique.
With carriage unloaded (just arm weight no vehicle) and depressing the male quick release
coupler into a clear plastic beaker as shown for air bleeding remove the desired amount of oil to
align columns. A graduated beaker as used in paint shops for auto paint allows the measurement
of oil removed.
Using this approach, it is possible to get the carriages exactly aligned.
Initially you can get the carriage close by fully lowering the carriages and bleeding. (Some
customers also like to depress the cylinder to bottom out, however this is not essential.)
Having done this simple approach, it is assumed there is some measured variation and you want
to optimize this.
If oil lines are unbalanced the difference is noticeable quickly. You only need to lift up to
500-‐1000mm to get accurate measurements of difference as shown below.
Pic 4: Measuring of carriage height.
For each 10mm out of alignment you bleed 10ml of oil out of the line connected to that side. If
you see air bubbles in the oil you have not bled the system properly or have a leak in your oil
lines somewhere.
Do another test lift and measure again.
You will soon learn how much to bleed and be able to tell how the difference in clicks relates to
oil difference.
This can be done loaded with a vehicle or not. Depending on your setup it is possible to get the
hoist to lift level. Some variation may occur with different loads but still be in the desired range,
typically it remains constant however.
•
Customers have also used the following technique.
With the carriages at lowest position continue to lower the cylinder rod to its zero position are
left at lowest position by breaking fitting or quick release coupling whilst pushing down on the
