Husqvarna K770 SmartGuard, Workshop Manual

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on page 10. There is also a sealing plug that replaces
the decompression valve.
Use a pressure tester or equivalent for the test, refer to
Servicing tools overview on page 11.
1. Turn the crankshaft until the exhaust port is fully
open. The piston must be at its bottom point.
2. Put the sealing plug in the space for the
decompression valve.
3. At the exhaust port, attach the exhaust port seal on
the cylinder at the position for the muffler.
4. At the inlet port, loosen the 2 screws at the lower
part of the carburetor.
5. Put the inlet seal in position and put in the screw. Be
careful of the strap. Pull the lower part carefully.
6. Connect the pressure tester at the inlet port.
7. With the pressure tester, increase the pressure to 7
psi/0.5 bar. If the pressure decreases more than
down to 3 psi/0.2 bar after 30 seconds, there is a
leakage..
8. If there is a leakage, apply a solution of soap and
water or use a leakage spray to find it.
a) Examine the seals on the crankshaft.
b) Examine around the gaskets where the
crankcase halves are bonded and at the bottom
of the cylinder.
c) Look for cracks on the crankcase.
6.12.2 To remove the crankcase seal
To replace the crankcase seal rings, use a Husqvarna
puller and an assembly punch. Refer to Servicing tools
overview on page 12 and Servicing tools overview on
page 10.
1. Push down the puller and tighten the outer thread of
the puller in the sealing ring with a spanner.
2. Turn the T-handle of the tool to pull up the
crankcase seal.
3. Remove the crankcase seal in the same procedure
on the flywheel side.
1453 - 001 - 02.04.2020 Repair and servicing - 49