Model 640 & 640CC Instruction Manual
D01206676
Revision A February 2016
34
2.
Secure the Filter Housing in a vise and remove the Seat Retainer.
3.
Compressed air may be forced through the filter element to remove the debris
attached to the filter. The filter element may also be unscrewed from the filter
nipple and cleaned with solvent or a weak acid solution.
4.
Thread the filter onto the filter nipple. Install the filter element and filter seat
into the housing and secure tightly with the seat retainer.
5.
Install the filter back in the instrument. If transferring the oil from the pressure
vessel to the reservoir is still slow, replace the filter element.
Replacing the Low Pressure Filter Element
12.6
1.
Make certain all valves are closed.
2.
Open the AIR EXHAUST valve.
3.
Locate the blue, low-pressure oil filter housing.
4.
Remove the nut on the top of the filter housing. The filter bowl and filter
element will come off.
5.
Replace the filter element with a new element.
6.
Inspect the gasket and replace if necessary.
7.
Replace the bowl and filter element and install the nut. It may appear that the
filter element is too long, but the element will be compressed as the nut is
tightened which separates the filtered oil from the unfiltered oil.
8.
Check for leaks.
To minimize the mess, place a bucket or cup under the filter
housing to catch any oil that might spill.
Potentiometer Mechanism Resistor Replacement
12.7
1.
Remove shaft bearing retainer and potentiometer slider.
2.
Remove old resistor from mounting frame, being careful not to damage slot.
3.
Position new resistor over the slot in the mounting frame with the straight side
down. The connecting strip must be installed under the resistor in the groove
