Motor vehicles

DETAILED DESCRIPTION I claim: 1.
A truck comprising: a.
a chassis on which an engine is mounted; b.
a cab tiltably mounted on the chassis and in its operative position overlying the engine at least in part; c.
an enclosure surrounding the engine when the cab is in its operative position, the enclosure comprising substantially two parts, a first fixed part carried by the chassis and a second movable part carried by the cab so that when the cab is tilted the second part separates from the first part to expose at least part of the engine; d.
the engine enclosure having at least one air inlet in its leading end which is positioned in the front of the fixed part of the enclosure and therefore relatively low down and at east one air outlet located at the rear end of the enclosure in the second movable part of the enclosure and therefore relatively high up so as to promote convection currents within the enclosure for cooling the engine after it has been stopped.
2.
A motor road vehicle according to claim 1 wherein the enclosure has a plurality of air inlets in its fixed part, and a plurality of air outlets in its second movable part.
3.
A motor road vehicle as claimed in claim 2 in which each of the said outlets is fitted with a valve, said valve closing automatically in the event of a fire within the enclosure.
4.
A motor road vehicle as claimed in claim 1 in which seals are fitted on the joint edges of the second part of the engine enclosure, but not at the joint edges of the first part so that when the truck cab is tilted the seals between the first and second parts of the engine enclosure will be moved clear and be less likely to be damaged during maintenance of the engine.
5.
A motor road vehicle as claimed in claim 1 in which the engine enclosure has an undertray which is detachably secured to the underside of the front part of the enclosure.
6.
A motor road vehicle as claimed in claim 1 in which a fan is positioned in front of the enclosure and its outlet connected to the air inlet of the enclosure by at least one duct so that cooling air can be fed into the enclosure