Removal
Disassemble the engine (see section above "Disassembling and assembling the engine").
Remove the camshaft. When doing this, you need to act carefully, as the bearings usually stick to the shaft and can fall and get damaged when removing it.
Remove and mark the bearings.
Examination
Check the tightness of the gear fit on the camshaft.
Check the camshaft and camshaft for wear where the bearings are installed (i.e. are the working surfaces of the cams worn and are the surfaces of the protruding parts smooth?).
Check the wear of the camshaft gear tooth profile.
Check the clearance between the teeth of the camshaft and crankshaft gears. It should be 0.00-0.05 mm. The clearance can only be adjusted by installing a different camshaft.
The camshaft gear is of the correct size if, when carefully rotating it in different directions, a barely noticeable play is felt during the change in direction of rotation. The clearance between the gear teeth is too small if the camshaft lifts the crankshaft out of the bearings when it turns in the opposite direction.
If the clearance is excessively large, a camshaft with different dimensions can be installed. To identify gears of different sizes, digital markings are stamped on the end faces of the camshaft gears facing the cams (for example, "-1,0", "+1", "+2" etc.). The number shows by how many hundredths of a millimeter the radius of the pitch circle differs from the nominal size.
Caution! Do not confuse the number "0" with the "O" mark, which is used to install the timing gears. There are no differences or, accordingly, designations for the crankshaft gears.
Installation
Lightly file the edges of the bearing oil holes (if necessary). Install bearings (counting from the flywheel side) so that the protrusions are located in the recesses of the body. Bearing N3, as a centering bearing, takes on radial loads and therefore has flanges on both sides for the camshaft.
Lubricate the camshaft journals and cams with engine oil. Install the shaft so that the gear tooth marked "O" is located between the two crankshaft gear teeth marked with punched dots.
Visitor comments