Penny Hydraulics MezzLift, Service And Operation Manual

8 

Issue 1 

–

 ER - Oct 2019 

Mountings 

Check top and bottom mountings for security. These are to be re-examined under 
full load conditions during the testing procedure and inspected for movement. 

Cradle chain type 

Visually check chain attachment points on cradle. 

Check for free movement of cradle. 

Check rollers for free movement and wear. 

Apply LEP grease to any grease nipples. 

Chain sets 

Examine both drive & suspension chains for damage and wear. 

Visually check coupling points for security. 

Examine all sprockets & clear any debris from behind the bottom sprocket. 

Grease all four chains.   

Grease the motor and two bottom bearings via the grease nipples. 

Check suspension chain tensions with the platform near the top. They should be 
even with only hanging tension in the fall from the cradle to the bottom sprocket 
but no bunching of the chain when the cradle is lowered. Adjust as necessary 
using the two adjusters beneath the top sprocket. 

Check the drive chains for even tension. There should be no bunching of the 
chain when under load. If they need adjusting loosen the motor mounting plate 
bolts and use a bottle jack to push the assembly up so tightening the chains. 
Retighten the plate bolts. 

Hydraulic system 

Check that power pack is securely mounted. 

Check power pack and hose ends for leaks. 

Check oil level and top up as necessary using Tellus 32 hydraulic oil. 

Check that relief valve is not causing motor to stall by driving the platform into 
the end stops. 

Examine visible hose run for leaks and damage. 

Check and reposition hoses at the top of the column to ensure clearance on cradle 
rear axle. 

Check the ram whilst removed from the column for leaks or scoring to the piston.  
Do not attempt any ram repair on site but replace the complete unit if necessary. 

Check internal hose run or leaks and damage. 

Test 

Run up and down five times unloaded. It may not always be possible to go to the 
top. Check for smooth running and correct relief valve operation. 

Load with the largest standard load and run up and down five times. Check that 
the flow control valve gives the correct speed of descent. Check for partial 
porting of the control valve leading to loss of control over descent. Adjust relief 
valve to give constant speed of ascent. Examine hoist mountings. 

Repeat the unloaded test. Check for leaks. Check rope or chain tensions.