Mazda Trucks 1972-1986 Repair Guide

Diesel Fuel Sedimenter



Water should be drained from the diesel fuel sedimenter whenever the light on the instrument panel comes on or every 5,000 miles. More frequent drain intervals may be required depending on the quality of the fuel used.

The truck must be stopped with the engine off when draining the sedimenter. Fuel may ignite if sedimenter is drained while the engine is running or the truck is moving.

The instrument panel warning light (WATER IN FUEL) will glow when approximately 1 / 2 liter of water has accumulated in the sedimenter. When the warning light glows, shut off the engine as soon as safely possible. A suitable drain pan or container should be placed under the sedimenter, which is mounted inside the frame rail, underneath the driver's side of the cab. To drain the fuel sedimenter, pull up on the T-handle (located on the cab floor behind the driver's seat) until resistance is felt. Turn the ignition switch to the ON position so the warning light glows and hold T-handle up for approximately 45 seconds after light goes out.

To stop draining fuel, release T-handle and inspect sedimenter to verify that draining has stopped. Discard drained fluid suitably.