Chapter 8 – Cylinder and Piston
Service Manual AJP PR3/PR4 8 - 10
Piston must be aligned with the head of the
connecting rod, taking into account that the
mark “IN” is facing the intake side. Piston pin
may be lightly greased and then introduced
into the piston through the piston head and
piston rod.
Then should be introduced the respective
circlip in its cavity in the piston, preventing the
piston pin go out of his place.
After piston pin installation check that each
circlip is perfectly placed in piston housing
and with the circlip ends away from the cut.
Note:
The tips of this circlip should be away
from the existing cut in the piston to ease
removal and should be checked that the
circlip placement was well done without pin
prisons.
Remove protection plastic and adjust piston
rings to its correct position.
Piston ring ends must be with a 120º
mismatch between them. In the case of oil
rings, the ends can face exhaust, away 40
mm.
CYLINDER INSTALLATION
Note:
Be careful when placing the piston in
the cylinder to avoid damaging the segments
or the cylinder walls.
If the timing chain is installed on the
crankshaft gear, when installing the cylinder, it
must be passed by the timing chamber hole
and held in tension with a string or wire tied,
preventing it from falling into the crankcase or
jump out of gear on the crankshaft.
Apply engine oil on the cylinder walls and the
outer surfaces of the piston and segments to
ease installation.
The cylinder must be assembled on the piston
while at the same time manually compressing
each segment carefully to avoid damaging
