TOHATSU MFS 4 Service Manual

5-42
Power Unit
4st 4/5/6 2011
UP
＃1
＃2
＃4
＃5
＃3
T
T
UP
#2
#4
#3
#1#5
45°
45°
d
d
5
5
5
5
4
a
c
3
4
2
UP
b
1
4st OIL
4st
OIL
4st
OIL
4st OIL
37) Installation of Piston and
Connecting Rod
1. Install connecting rod 2, piston pin 3, and piston pin clip
4 to piston 1.
CAUTION
Be careful not to scratch piston surface
and damage rings.
2. Put expander 5 (#4) in the oil ring groove, and check that
ring end makes gap as shown.
3. While holding expander 5 (#4) gap with thumb, put upper
side rail (#3) into the groove so that the gap is away from
gap of expander 5 (#4) to the left by 90 degrees.
4. In similar way, put lower side rail (#5) into the groove so that
the gap is away from gap of expander 5 (#4) to the right by
90 degrees.
5. Install second ring (#2 taper) and top ring (#1) to piston.
Install top Ring (#1) and Second Ring (#2) so that their side
with manufacturer's identification d (T) faces upward (valve
side).
6. Bring their gaps are away from each other as shown.
· Point "3AB-UP" mark a of connecting rod and
"UP" mark b of piston to the same direction.
· Be sure to use new piston pin clip, and place
clip gap away from piston pin groove c as
shown.
· Be sure to install the connecting rod cap in
original position (direction).
· Install piston rings so that their gaps are away
also from thrust direction of piston and
direction piston pin.
· After installing piston rings, check that they
move smoothly.
4
Do not reuse.
MFS4-5-6Ech05110425.qxd11.4.2511:39AM  ページ42

TOHATSU MFS 4 Specifications

General

Brand	TOHATSU
Model	MFS 4
Category	Outboard Motor
Language	English