Abstract: A throttle opening controller for one embodiment of a small planing boat includes: a throttle valve for changing the degree of opening in response to displacement of a throttle lever; a remaining fuel amount detector; a fuel consumption calculating means; and a throttle opening limiting means. In one embodiment, when a remaining fuel amount detected by the remaining fuel amount detector is equal to or below a preset value L1, the fuel consumption calculating means starts calculating total fuel injection amount. When a value, obtained by subtracting the total fuel injection amount from the preset value L1, is equal to or below a threshold L0, the throttle opening limiting means determines the degree of opening of the throttle valve based on an opening rate (k). An internal space of a fuel tank can be divided using a vertical partition into plural chambers. In addition, a knock sensor can be provided for an engine.

Abstract: A small watercraft engine having a lubrication system including a lubrication oil reservoir. In an upper portion of the reservoir, a breather assembly is mounted which aids in separating liquids from vapor traveling therethrough. A lower surface of the baffle arrangement includes at least one aperture which allows vapor from the main portion of the lubricant reservoir to pass upwardly into the breather arrangement. A skirt extends downwardly around the aperture so as to aid in preventing liquid lubricant from passing through the aperture.

Abstract: A ventilation system for a watercraft engine includes an improved construction that can inhibit oil in an oil container from flowing into an air induction system even if the watercraft capsizes. The engine includes an engine body and an air induction system that introduces air to combustion chambers. A lubrication system is arranged to lubricate at least a portion of the engine body with lubricant oil. The lubrication system includes an oil tank assembly out of the engine body. A ventilation system is arranged to separate a gaseous component from a liquid component. The ventilation system includes a separator configured to separate the gaseous component from the liquid component. A ventilation passage connects the separator with the air induction system. A return passage couples a bottom portion of the ventilation passage with inside of the engine body.

Abstract: A watercraft includes a lubrication system having a lubricant pump assembly and a lubrication reservoir defined between a lower crankcase member and an oil cover. At least one oil passage connects a crankcase to the reservoir. The oil cover, or both the oil cover and the crankcase member may contain one or more baffles configured to impede a flow of oil away from the lubricant pump assembly. Additionally, the cover may include one or more projections securing one or more plugs within one or more countersink portions of the crankcase member.

Abstract: A ventilation system for a watercraft engine includes an improved construction that can inhibit oil in an oil container from flowing into an air induction system even if the watercraft capsizes. The engine includes an engine body and an air induction system that introduces air to combustion chambers. A lubrication system is arranged to lubricate at least a portion of the engine body with lubricant oil. The lubrication system includes an oil tank assembly out of the engine body. A ventilation system is arranged to separate a gaseous component from a liquid component. The ventilation system includes a separator configured to separate the gaseous component from the liquid component. A ventilation passage connects the separator with the air induction system. A return passage couples a bottom portion of the ventilation passage with inside of the engine body.

Abstract: A method of plating an aluminum alloy, of which the steps are small in number and the productivity is improved as compared with conventional zincate conversion or anodic oxidation methods and which attains a decrease in cost and obviates the use of mixed acids, and a plated aluminum alloy of which the coating has excellent adhesion, the method comprising the steps of carrying out anodic etching of a silicon-containing aluminum alloy to protrude silicon from the surface of the aluminum alloy, optionally carrying out anodic oxidation of the aluminum alloy on its surface from which the silicon is protruded, and plating the aluminum alloy, and the plated aluminum alloy containing silicon in a state where the silicon bridges the aluminum alloy and the plating layer.

Abstract: A primary object of the invention is to provide a method of producing rigid polyurethane foams using 1,1-dichloro-1-fluoroethane (HCFC-141b) as the blowing agent while substantially avoiding the formation of decomposition products from HCFC-141b. The above object can be achieved by a method of producing rigid polyurethane foams which comprises reacting a polyol with an organic polyisocyanate for foaming in the presence of HCFC-141b and a stabilizer therefor and in the presence of an organic metal catalyst and/or an imidazole compound catalyst and by the thus-produced rigid polyurethane foams.

Abstract: A method of producing an open cell rigid polyurethane foam which comprises reacting a polymethylene polyphenylisocyanate prepolymer with a polyol at an NCO/OH equivalent ratio of 1.3 to 3.0 by use of a blowing agent substantially comprising water in the presence of a catalyst, a foam stabilizer and a cell opening agent.

Abstract: A method of producing an open cell rigid polyurethane foam which comprises reacting a polyol with a polymethylene polyphenyl polyisocyanate prepolymer with a monool exemplified by diethylene glycol monomethyl ether by use of a substitute such as 1,1-dichloro-1-fluoroethane or methylene chloride as a volatile blowing agent, or a mixture of the volatile blowing agent with water, for trichlorofluoromethane as a blowing agent in the presence of a catalyst, a foam stabilizer and a cell opening agent. The resultant open cell rigid polyurethane foam has a cell size of about 200-250 microns, and is suitable for use, for example, as a core material in a vacuum heat insulating material. The foam may be enclosed in a container under a vacuum of 0.1-0.01 mmHg readily attainable to provide a vacuum heat insulating material of a high heat insulating performance.