How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask GMTechBernard Your Own Question
GMTechBernard, Shop Foreman - GM World Class Tech
Category: Chevy
Satisfied Customers: 2158
Experience:  GM
Type Your Chevy Question Here...
GMTechBernard is online now
A new question is answered every 9 seconds

How to set timing on a 4.

Customer Question

how to set timing on a 4.3 v6 engine on a 95'' chevrolet astro van
Submitted: 9 years ago.
Category: Chevy
Expert:  GMTechBernard replied 9 years ago.
  • Engage the parking brake and block the wheels.
  • Place the transmission is neutral.
  1. Refer to the important engine information label located in the engine compartment on the label.
  2. Put the Ignition Circuit (IC) system in the bypass mode by disconnecting the "Set Timing" connector. This is a single wire sealed connector that has a tan with black stripe lead. This connector breaks out of the engine wiring harness conduit adjacent to the distributor.
  3. With the ignition switch "OFF," connect the pickup lead of the timing light to the number one spark plug. Use a jumper lead between the wire and plug or an inductive type pickup. NOTE: Do NOT pierce the wire or attempt to insert a wire between the boot and the wire. Connect the timing light power leads according to manufacturer's instructions.
  4. Start the engine, and aim the timing light at the timing mark. The line on the balancer or pulley will line up at the timing mark. The timing specification isZero Degrees BTDC. If a change is necessary, loosen the distributor hold-down clamp bolt at the base of the distributor. While observing the mark with the timing light, slightly rotate the distributor until the line indicates the correct timing. Tighten the hold-down bolt, and recheck the timing.
  5. Turn "OFF" the engine and remove the timing light. Reconnect the number one spark plug wire, if removed.
  6. Reconnect the "Set Timing" connector.