SIDE HOUSING CONSTRUCTION


BHE011010908T04

• To speed catalytic activation during cold-engine start, inserts have been installed in each exhaust port to maintain the higher temperatures. Above each exhaust port is a secondary air port, which sends secondary air close to the combustion chamber.

• The housing forms the engine outer core with the intermediate housing positioned between the two rotor housings, which are further enclosed by front and rear housings. The components of the housing are positioned precisely using tubular dowel pins.

• On the front and rear housings are the installation bosses for the stationary gears that regulate the rotational movement of the rotors supporting the eccentric shaft.

• On the front housing are the bosses for installing the oil pump and the oil strainer.

• On the intermediate housing are the bosses for the primary injectors, which are placed near the combustion chambers for semi-direct injection. There are also additional bosses for the oil level gauge and the oil filler pipe.

• On the rear housing are the bosses for installing the oil filter and the oil pressure regulator.

• The special cast iron side housings are processed with soft-nitriding for improved wear resistance of the rotor friction surfaces. Wall thickness in each area of the side housings has been reduced for weight reduction.

• Each of the housings are sealed together with rubber seals at the inner and outer circumferences of the water jacket surrounding the rotor friction surface.

1
Stationary gear installation boss
2
Oil pump installation boss
3
Oil strainer installation boss
4
Front housing
5
Seal rubber
6
Front rotor housing
7
Tubular dowel
8
Exhaust port
9
Intake port
10
Intermediate housing
11
Oil level gauge installation boss
12
Oil filler pipe installation boss
13
Rear rotor housing
14
Auxiliary port (high power only)
15
Oil filter installation boss
16
Rear housing
17
Pressure regulator installation boss
18
Primary injector installation boss
19
Secondary air port
20
Insert
21
Rear housing cross-sectional view

• The anti-wet port with a projection is located on the bottom edge of the primary port. With the anti-wet port, jet air from the jet air fuel mixing nozzle, located at the primary port outlet of the intake manifold, flows upward, and atomization is accelerated under low load when air intake velocity is slow. At the same time, air current is formed so that the air-fuel mixture flows to the spark plugs. As a result, stable combustion is obtained.

1
Jet air fuel mixing nozzle
2
Anti-wet port
3
Jet air
4
Primary port