d

dry film lubricant

Glossary “dry film lubricant” Definition:
Petroleum based chemical used to lubricate operating parts during assembly, prior to engine start up, to provide lubrication until oil is circulated after start up.

drum maximum diameter

Glossary “drum maximum diameter” Definition:
The largest diameter, generally 0.060 inch (1.5 mm) over originally to which a brake drum can be machined or worn before it is considered unsafe.

dry compression test

Glossary “dry compression test” Definition:
A test to determine engine compression. After the engine has reached operating temperature, remove all spark plugs, disable fuel and ignition systems, prop open the throttle, install the compression tester into the spark plug hole. Crank the engine at least five compression strokes and record the reading. Repeat these step for the remaining cylinders. Compression readings are considered to be within specification if the lowest reading is within 75% of the highest reading. When performed on a diesel engine, use a compression gauge designed for diesel engines.. Compression gauge is attached through the glow plug hole.

drum brake

Glossary “drum brake” Definition:
A type of brake in which stopping friction is created by shoes pressing against the inside of the rotating drum.

drop center wheel

Glossary “drop center wheel” Definition:
A conventional wheel that has a space in the center for one bead to fit into while the other bead is being lifted over the rim flange.

drop through

Glossary “drop through” Definition:
The undesirable sagging or surface irregularity encountered when brazing or welding; caused by overheating with rapid diffusion between the filler metal and the base metal.