A technique for making air less likely to enter a strainer in an internal combustion engine in which the strainer is supported by a drain bolt. In an internal combustion engine in which a drain bolt supports a strainer and is configured to discharge a drain is attached to a bottom of a sump. A drain hole into which the drain bolt is screwed and a strainer hole are arranged coaxially. A crankcase is provided with an oil passage through which oil is returned to the sump. The oil passage includes a first passage through which the oil flows in a direction away from the strainer, a return passage that turns around from a forefront end of the first passage, and a second passage through which the oil flows from a forefront end of the return passage toward the strainer.

The volume of lubricating oil stored in the sump of an internal combustion engine for a vehicle is in significant excess of the volume of oil circulating through the engine at any one time. The circulating oil, drawn from the sump, may be rapidly heated during its passage through the engine, but the excess volume remaining in the sump dilutes and cools the circulating oil as it returns to the sump. By separating the oil volume into a portion which is circulated through the engine and a second portion which has only limited opportunity to mix with and cool the circulating oil the circulating oil may attain its operating temperature more rapidly. Once the stored volume of oil in the engine has also reached its operating temperature the circulating oil and stored oil may be recombined.

A lubricant pan for a vehicle includes a receiving region in which a lubricant is at least temporarily receivable, a first wall element, and a second wall element. A temperature-control channel is disposed between the first wall element and the second wall element and a temperature-control medium is flowable through the temperature-control channel. A core that is porous and permeable to the temperature-control medium is disposed in the temperature-control channel between the first wall element and the second wall element. The temperature-control medium is introducible into the temperature-control channel via a first connector and the temperature-control medium is dischargable from the temperature-control channel via a second connector.