For overhauling drain valves (order-related),
see 8.13
For checking safety valves, see 8.14 (according to the owner's instructions)
Operating hours Date
104.
fm
8.4 Table of tightening torques
8.5 Checking the screw connection
Check all fittings and screw connections for tightness, re-tighten as necessary. This includes:
– Coolers and air lines
– Fittings for pipe lines and flexible hose lines – Cylinder heads
– Cylinders
– Motor, coupling and flange;
– Monitoring systems and switchgear – Base frame/foundation
– Accessories and ancillary equipment
Note!
Carry out a check 50 h after completing a maintenance
routine. Check all screws and nuts affected by maintenance to
see if they are tight.
Bolts/screws Tightening torque
Flywheel fixing screw 175 Nm Cylinder head screws 1st stage 55 Nm Cylinder head screws 2nd stage 75 Nm
Maintenance
WP 45L_ BA1_ en_1 104. fm 618.6 Changing the air filter insert
1. Open fasteners (position 1) and remove cover (position 2) of the air filter.
2. Remove used air filter insert (position 3).
3. Clean housing (position 4) using a suitable solvent (e.g. kerosene) and wipe out with a lint-free rag.
4. Insert new air filter insert.
5. Insert cover and close fasteners.
2
4 3
104.
fm
8.7 Change oil
1. Allow the compressor to run for about 5 minutes to warm up. 2. Place oil catchpan (of a size sufficient for the oil sump
capacity, see Chapter 4) beneath the oil drain cock (3). 3. Unscrew the oil fill cap (1).
4. Open oil drain cock (3). 5. Wait until all oil has drained. 6. Close oil drain cock (3).
7. Pour in new oil and check the oil level with the dipstick (2). The filling level must be between the upper and lower gauge mark on the dipstick.
8. If the oil level is reached, replace the dipstick (2) and screw the oil fill cap (1) shut.
Note!
Use oil according to lubricant table (see Chapter 10) or according to oil recommendation for Sauer compressors.
1
3 2
Maintenance
WP 45L_ BA1_ en_1 104. fm 638.8 Checking valves
Removing valves
1. Loosen the clamp on the air filter and replace the air filter. 2. Disconnect the pipe fittings and hose lines on the cylinderheads.
3. Unscrew the cylinder head nuts and remove the cylinder heads.
4. Carefully remove the valves.
Checking valves
5. Check valves for visible: – Damage– Oiling – Coking
– Corrosion and – Humidity
If there is damage, heavy coking or corrosion, replace valves.
Determine the cause (see Chapter 7). 6. Clean all mating surfaces.
Installing the 1
ststage valve
Note!
Install all valves with new gaskets and washers. Do not reuse old gaskets and washers.
Only use genuine Sauer spare parts.
Installation of old or other gaskets and washers may lead to leakage and may cause substantial damage to the compressor.
4 3 2
1
104.
fm
7. Place new cylinder head gasket (3) within the stud bolts onto the cylinder (5). Insert the new low-tolerance gasket ring (4) into the groove of the valve (1) Now insert the valve (1) into the cylinder head (2) from below.
(Caution: The low-tolerance gasket ring may not shift while doing so).
8. Hold the cylinder head and valve. Now carefully slide both parts together over the stud bolts and place them onto the cylinder head gasket.
Maintenance
WP 45L_ BA1_ en_1 104. fm 65Installing the 2
ndstage valve
10. Insert new O-ring (3) into the groove between cylinder (5) and valve (4). Insert new cylinder head gasket (2) between valve (4) and cylinder head (1).
11. Tighten the cylinder head screws by hand.
12. Screw pipe fittings and hose line onto the cylinder heads and tighten by hand.
13. Securely tighten the cylinder head screws. Observe the tightening torque (see Chapter 8.4).
14. Securely tightening pipe fittings and hose line
1 2
3 4
104.
fm
8.9 Replacing valves
Remove and install valves as described in Chapter 8.8. Make sure to completely replace the valves when doing this.
Note!
Valves which have reached their service life must be replaced and disposed of.
We do not recommend repairing used valves due to material fatigue.
Maintenance
WP 45L_ BA1_ en_1 104. fm 678.10 Replacing piston rings, gudgeon pins and
gudgeon pin rings
1. Remove cylinder heads and valves as described in Chapter 8.8.
2. Carefully remove the cylinder. Hold the piston while the cylinder comes off.
3. Remove the gudgeon pin circlips, push out the gudgeon pin and remove the piston.
4. Remove all piston rings from the respective pistons and clean the pistons.
Checking
pistons and
cylinders
5. Check cylinders and pistons for scoring marks and excessive wear. Replace parts as required.
Note!
If the piston is not held while the cylinder is being pulled off, it will strike the crankcase.
Note!
Always replace all piston rings by new ones.
Note!
If edges can be felt on the piston running surface in the cylinder, these edges must be broken using a Flexhon brush or a Scotch-
Brite abrasive pad. As otherwise the edges may damage the
104.
fm
Measuring
piston wear
1. 1. measurement:
Insert the piston ring into the cylinder approx. 5 mm (1) beneath the upper edge (above the turning point of the top piston ring) and measure the gap clearance using a feeler gauge in the area (3) where the piston rings are not running. 2. 2. measurement:
Slide the piston ring down by approx. 50 mm (2) (beneath the turning point of the lowest piston ring) and measure the gap clearance in the wear area (4) again.
Note!
It is possible to measure used and new piston rings.
1 2
3
Maintenance
WP 45L_ BA1_ en_1 104. fm 693. Calculate the difference between the two gap clearances (1) of
measurement 1 and measurement 2 and compare it with the gap clearance difference values in the table.
Replacing the
gudgeon pins/
gudgeon pin
bearings (small-
end bearing)
1. Press gudgeon pin bearing into the connecting rod's small end with a suitable tool and replace it by a new gudgeon pin bearing.
2. Install the pistons to the connecting rods. To do this, press the new gudgeon pin in and insert the circlips.
stage WP45L gap clearance difference
1 0.45 mm
2 0.30 mm
1
Note!
J. P. SAUER & SOHN'S Customer Service is to be consulted if the difference between the two gap clearances is greater than indicated in the table above.
Note!
104.
fm
Installing piston
rings
3. Install piston rings in the respective piston. Make sure they are in the correct position: piston rings having an asymmetric cross section are marked with “TOP” on one of the surfaces. The marked face must be at the top when the piston ring is installed (see illustration).
4. The piston ring locks should be staggered around the piston circumference.
Installing
cylinder and
valves
5. Insert a new cylinder foot gasket for each cylinder. 6. The cylinders are installed in reverse order to their
disassembly.
7. Install valves and cylinder heads as described in Chapter 8.8.
Item Designation 1 Piston 1ststage 2 Piston 2ndstage TOP TOP TOP TOP 1 2
Maintenance
WP 45L_ BA1_ en_1 104. fm 718.11 Replacing the coupling flexible insert
1. Shut down the compressor and secure it against restarting. 2. Support the compressor (1) under the bell housing.
3. Unscrew fixing screws (2) of the electric motor (3).
4. Lift the electric motor (3) carefully at the lifting eye bolts (4) (see Chapter 5.1).
5. Pull the electric motor (3) carefully away from compressor (1). 6. Replace coupling flexible insert (5).
7. Carefully slide the electric motor (3) onto the compressor (1) and tighten the fixing screws (2).
8. Remove the support under the bell housing.
9. Reinstall the disconnected connecting lines and pipes.
Note!
Applies to Sauer compressors with electric motor.
5
104.
fm
8.12 Checking the condensate separator
Separator
1. Shut down the compressor and secure it against restarting.2. Disconnect installed air lines and hoses. 3. Remove the 2nd stage safety valve.
4. Remove the separator housing from the crankcase. 5. Remove the separator cover.
6. Check the separator for damage.
7. Clean the separator housing using a suitable solvent (e.g. kerosene).
8. Blow out solvent (e.g. kerosene) with air. 9. Assembly follows the steps in reverse order.
Item Designation
1 Separator 1st stage 2 Separator 2nd stage
3 Separator head 1st stage
4 Separator head 2nd stage 5 Safety valve 1st stage 6 Safety valve 2nd stage
1 2
6
5 4