- P -

Pintle Hook

A pin installed in the rear of some vehicles for attaching a tow bar.

Pintle Valve

The ball and seat found inside a thermostatic expansion valve, attached to the diaphragm, which causes it to open and close in response to pressure changes.

PIP

Profile injection pick-up.

Pipe

An exhaust system.

Pipe Brace

A brace that extends between opposite hangers on a spring or air-type suspension.

Pipe Dream

An illusionary fantasy plan, or way of life.

Pipes

A dual-exhaust system.

Piston

1. An engine part that reciprocates in the cylinder and transfers the force of the expanding gases via the piston pin and connecting rod to the crankshaft. 2. A round, caliper component in a disc brake that is moved outward by fluid pressure to press the pads against each rotor face. 3. An aluminum or sintered-iron component of a drum brake inside a wheel cylinder that supports the cylinder cup. 4. That part of a compressor that is driven by a crankshaft to compress vapor. 5. A small cylinder fitted inside a hollow cylinder which moves back and forth by fluid pressure to transmit reciprocating motion inside the transmission.

Piston Boss

That part of the piston which supports the piston pin.

Piston Bushing

A bushing that is pressed into the upper end of the connecting rod when free-floating pins are used.

Piston Crown

The top of the piston.

Piston Displacement

The cylinder volume displacement by the piston as it travels from the bottom to the top of the cylinder during one complete stroke.

Piston Markings

Marks on a piston which are used to identify piston oversize and the front of the piston.

Piston Material

Metal used in piston construction, usually cast- or forged-alloy aluminum.

Piston Oil Ring

A term used for oil ring.

Piston Oil Squirt Hole

A term used for oil squirt hole.

Piston Oiler

A device that injects oil into the piston as an aid to carry away heat from the piston crown.