Checking The Piston; Checking The Piston Ring End Gap; Checking The Oil Pump For Wear - HUSABERG FE 450 Repair Manual

SERVICING THE INDIVIDUAL PARTS

CHECKING THE PISTON

– Replace the piston if oil consumption is high or the
piston skirt is excessively grooved.
– If the piston is to be remounted:
1. Check the piston bearing surface for damage
2. Piston ring grooves: use a feeler gauge (A) to measure
the piston ring clearance in the piston ring groove.
The piston rings must move freely in the groove. Use
old piston rings or sandpaper (400 grit) to clean the
D
piston ring grooves.
3. Check the piston rings for damage and end gap.
10
Mount the oil scraper ring with the "O" mark facing up.
Mount the rectangular ring with the "O" mark facing up.
4. Replace piston pins that are badly discolored or have
visible running marks. Place the piston pin in the
conrod and check for clearance.

CHECKING THE PISTON RING END GAP

– Insert the piston ring in the cylinder and align with the
piston (approx. 10 mm under the upper edge of the
cylinder).
– Use a feeler gauge (A) to measure the end gap.
Compression ring : max. 0.80 mm
Oil scraper ring : max. 1.00 mm
If the end gap is larger than indicated above, check the
cylinder for wear. If the cylinder wear is within the
tolerance limits, replace the piston ring.

CHECKING THE OIL PUMP FOR WEAR

– Insert the inner rotor in the engine case with the mark
facing towards the outside and the outer rotor with the
mark facing towards the inside.
– Use a feeler gauge (A) to measure the wear:
Outer rotor - oil pump housing: max. 0.20 mm
Outer rotor – inner rotor: max. 0.20 mm
Wear limit: 0,15 mm
A
A
A A