Idle Speed & Ignition Timing

Ensure idle speed and base ignition timing are set to specification. If necessary, see ADJUSTMENTS article in the ENGINE PERFORMANCE section.

IGNITION TIMING SPECIFICATIONS

Application

Man. Trans.

⁽¹⁾ Auto. Trans.

B4000 ⁽²⁾

8-12 @ 475-575

Navajo

⁽³⁾

⁽¹⁾	Place automatic transmission in Park.

⁽²⁾	Connect jumper wire between terminals TEN and GRN of diagnostic connector.

⁽³⁾	Base (initial) timing is preset at 10 degrees BTDC and is not adjustable. To check timing, see ADJUSTMENTS article in the ENGINE PERFORMANCE section.