Sperre HLF2/77, Instruction Manual

Instruction manual for compressor type HLF2/77 

Page 7 

Bearings - Dismantling and Assembly 

Important: Work on bearings requires great care and scrupulous cleanliness. 
 
Worn or damaged crankshaft bearings should be replaced complete. Replacement of parts of 
the bearings is not satisfactory. Bearings dismantled from shaft and/or connecting rod should 
always be replaced with new bearings.  

Crankshaft bearings 

 
Dismantle as follows: 
1.  Remove the outer ring from the connecting rod, using a hydraulic press. 
2.  Remove the inner ring from the crankpin by heating it rapidly with a welding torch, then push it off 

the pin by means of a screwdriver or the like. If necessary, grind a notch in it to reduce its tension. 

3.  Fit a new outer ring to the connecting rod by using a hydraulic press. 
4.  To fit the inner ring, heat it in an oil bath or on an electric hotplate to 80 – 100 °C before sliding it 

onto the pin. 

 
 
Gudgeon pin bearings 

 
Dismantle as follows: 
1. Remove 

seeger 

rings. 

2.  Press out the gudgeon pin. If necessary, heat the piston slightly. 
3.  Use a hydraulic press to remove and re-install the gudgeon pin bearing in the connecting rod. 
 

Important: Check that there is axial play between connecting rod and piston after installation. 

 
 
Main bearings 

 
Dismantle as follows: 
1.  Remove the crankcase cover and detach the counterbalance at the end of the crankpin. 
2.  Dismantle the electric motor, coupling piece, coolers and flywheel. 
3.  Dismantle cylinder heads, pistons and connecting rods as described under ”Piston and connection 

Rod”. 

4.  Pull the bearing housing and crankshaft clear of the crankcase. 
5.  Remove seeger ring and pull the crankshaft out of the bearing housing. Carefully tap the bearings 

off the shaft and bearing housing respectively. 

 
Before fitting the bearings, heat them in an oil bath to about 100°C. Ensure that the seeger rings are 
correctly placed in their respective slots. 
 
Assembly is done in the opposite order. 
 
 

CCG DOC NO. 346055