VEB BERLIN SR59, Руководство по эксплуатации

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5.3 Removal of cylinder
1. Remove fuel tank.
2. Loosen exhaust´s bolt and nut (located at right traverse) located at the bracket and
remove exhaust.
3. Remove cylinder head as described in 5.2.
4. Loosen clamping screw at the carburetor connector and remove carburetor from
intake socket.
5. Pull cylinder out upwards (Neck of cylinder should be waggled out of dowel pin).
Mind the gasket !
6. Use a clean cloth to cover up the crank case.
5.4 Removing the piston
1. Remove cylinder as described in 5.3.
2. Remove circlips from piston pin (make sure, that the circlips don´t spring off !)
3. Incase the piston pin is stuck in the piston, carefully heat up the piston (using a
bunsen burner for example).
4. When the heat starts expanding towards the bottom end of the piston pin, press pin
out with a spike.
5. Never hammer the piston pin out of the piston !!
5.5 Inspecting or exchanging piston rings
1. Remove cylinder as described in 5.3.
2. If the piston pin is still stuck in the piston, the necessary work can be done without
removing the piston.
3. Remove piston rings using a pair of piston ring pliers or three narrow pieces of tin, to
avoid breaking or overexpanding the rings. Mark the rings in such a way, that they
can later be reinstalled in the same position in the same groove !!
4. Cleanse the piston rings and the grooves from any coal or residue. CAUTION !! do
not damage rings with inappropriate tools !!
5. Insert the piston rings into the bore one by one with the help of a cylindric shaped
piece of wood or an old piston. Push piston rings down into the bore by about half a
stroke length.
6. Now check the piston rings gap using a measuring gauge. If the gap exceeds
0.5mm, the rings need to be exchanged.
7. Reinsert rings into piston grooves, using the tools and measures described for
removal. Do not lubricate rings !!