Piston Ring; Outline Of Piston Ring; Structure Of Piston Ring; Function Of Piston Ring - Kubota D1803-CR-E4 Workshop Manual

MECHANISM
2. Engine body

2.9 Piston ring

2.9.1 Outline of piston ring

Piston rings primarily maintain air tightness of the
combustion chamber.

2.9.2 Structure of piston ring

The piston rings are top ring (barrel face), second ring
(taper face), and oil ring.
(1) Top ring
(2) Second ring
(3) Oil ring
(4) Expander
(5) Plane (barrel face) type (for
D1803-CR-E4, and V2403-
CR-E4 model)

2.9.3 Function of piston ring

1. Maintain airtightness of the combustion chamber
during the compression stroke and combustion
stroke.
2. Wipe down oil on the cylinder wall. Also prevent oil
getting into combustion chamber.
3. Transfer piston heat to the cylinder wall.
4. Support piston posture.
D1803-CR-E4,D1803-CR-TE4,D1803-CR-TIE4,V2403-CR-E4,V2403-CR-TE4,V2403-CR-TE4BG,V2403-CR-TIE4
(6) Key-stone (barrel face) type
(for D1803-CR-TE4, -TIE4
and V2403-CR-TE4, TE4BG,
-TIE4 model)
(7) Inner bevel (taper face) type
(8) Bevel cutter type

2.9.4 Specification of piston ring

Top ring
Second ring
Service speci-
fication of pis-
ton ring gap
Oil ring

2.10 Connecting rod

2.10.1 Outline of connecting rod

The connecting rod connects the piston and the
crankshaft.
The connecting rod transfers the combustion pressure
received by the piston to the crankshaft.

2.10.2 Structure of connecting rod

The connecting rod is made up of a connecting rod cap
and connecting rod etc.
(1) Small end
(2) Big end
(3) Connecting rod cap
4. ENGINE
0.20 to
0.35 mm
0.0079 to
0.013 in.
0.30 to
D1803-CR-E4 0.45 mm
V2403-CR-E4 0.012 to
0.017 in.
D1803-CR-
0.40 to
TE4, -TIE4
0.55 mm
V2403-CR-
0.016 to
TE4, -TE4BG,
0.021 in.
-TIE4
0.20 to
D1803-CR-E4 0.40 mm
V2403-CR-E4 0.0079 to
0.015 in.
D1803-CR-
0.25 to
TE4, -TIE4
0.45 mm
V2403-CR-
0.0099 to
TE4, -TE4BG,
0.017 in.
-TIE4
(4) Small end bushing
(5) Bearing metal
4-7
KiSC issued 12, 2018 A