はじめに
Use this guide to replace the piston assembly in your Echo Chain Saw CS-4910 (2020).
Although it's not necessary to remove the guide bar, it's highly recommended you do so to minimize any damage to the chain and to yourself.
必要な工具と部品
-
-
Make sure you have the ignition switch turned off before starting your repair.
-
-
-
Use a 13 mm wrench to loosen and remove the two nuts securing the sprocket guard.
-
-
-
Push the guide bar towards the back of the device to unclip the rest of the saw chain.
-
Pull the guide bar away from the device to separate the saw chain from the clutch drum.
-
Remove the guide bar and the saw chain.
-
-
-
Use a flathead screwdriver, or a 3 mm hex key, to remove the three 18 mm screws securing the engine cover.
-
-
-
Pull the engine cover straight up off the engine.
-
Remove the engine cover.
-
-
-
Use your fingers to pull the top-most fuel pipe out of the carburetor.
-
-
-
Remove the four screws securing the carburetor and the air filter adapter:
-
Use a 3 mm hex key to remove the two 20 mm-long screws.
-
Use a 4 mm hex key to remove the two 53 mm-long screws.
-
-
-
-
Pull the air filter adapter straight off the carburetor and remove it.
-
-
-
With the carburetor's choke valve facing you, tilt the carburetor up and to the left to expose the right-most fuel pipe.
-
-
-
Remove the five screws securing the handle:
-
Use a 4 mm hex key to remove the four 24 mm-long screws (on the side and bottom).
-
Use a 3 mm hex key to remove the 18 mm-long screw.
-
-
-
Use a 3 mm hex key to remove the two 20 mm-long screws securing the intake insulator.
-
-
-
Use a flathead screwdriver to fold the lip of the intake bellows inside the intake insulator.
-
-
-
Insert a flathead screwdriver between the intake bellows and the cylinder head.
-
Pry with the screwdriver to separate the intake bellows from the cylinder head.
-
Remove the intake bellows.
-
-
-
Use a 9/16 inch wrench to loosen the decompression valve assembly.
-
-
-
Pull the decompression valve assembly straight out of the cylinder head and remove it.
-
-
-
Use a 4 mm hex key to remove the two 23 mm-long screws securing the muffler.
-
Use a 3 mm hex key to remove the 10 mm-long screw securing the muffler plate.
-
-
-
Use a 4 mm hex key to remove the four 25 mm-long screws securing the cylinder head.
-
-
-
Lift the cylinder head away from the chassis to expose the piston.
-
Remove the cylinder head.
-
Make sure the two black piston rings are aligned in their grooves so the piston can compress properly in the cylinder head.
-
Apply two-stroke oil to the piston head and the cylinder walls before reinserting the piston.
-
-
-
Use snap ring pliers, or a flathead screwdriver, to remove one of the piston snap rings.
-
Repeat this procedure for the snap ring on the opposite side of the piston.
-
-
-
Flip the chain saw on its side so the clutch drum is facing upward.
-
-
-
Grip the bottom of the piston.
-
Use a hammer and a pin punch to tap the piston pin through its recess.
-
Remove the piston pin.
-
-
-
Pull the piston off of the piston rod to disconnect it from the crankshaft.
-
Remove the piston, its needle bearing, and the two washers.
-
-
-
Use a pair of pliers to remove the cylinder head gasket from the crankcase.
-
To reassemble your device, follow these instructions in reverse order.
To reassemble your device, follow these instructions in reverse order.
ある他の人がこのガイドを完成しました。
