Do I have to disconnect the vacuum advance on distributor first to set my ignition timing on a 69 ford p/u with a 360 cid motor ?

the degrees advance will be 10 degrees on the crank pulley. Loosen the distributor clamp so that you can turn the distributor . Set the points to the point gap. Place the pulley timing on 10 degrees . Turn the distributor in the direction of rotation until the points are closed . Turn on the ignition and advance ( turn against direction of rotation) the distributor until you hear a click. If you have the coil lead out of the coil when you hear the click you will get a spark from the HT lead. Lock up the distributor clamp at this point and you will be spot on timing. On most engines the recommended advance setting can vary a little so you may be able to advance it just a bit to make it run better . Use a light to check for how far advanced you are. A max of 12 degrees will be allowable.

255 cid (4.2L), 302 cid (5.0L), 360 cid (5.9L), 390 cid (6.5L), 460 cid (7.5L) V8 engines Firing order: 1-5-4-2-6-3-7-8 Distributor rotation: Counterclockwise




351 cid W & M (5.8L), 400 (6.6L) engines Firing order: 1-3-7-2-6-5-4-8 Distributor rotation: Counterclockwise

FIRING ORDERS NOTE: To avoid confusion, remove and tag the spark plug wires one at a time, for replacement. If a distributor is not keyed for installation with only one orientation, it could have been removed previously and rewired. The resultant wiring would hold the correct firing order, but could change the relative placement of the plug towers in relation to the engine. For this reason it is imperative that you label all wires before disconnecting any of them. Also, before removal, compare the current wiring with the accompanying illustrations. If the current wiring does not match, make notes in your book to reflect how your engine is wired. Fig. 1: 300 cid (4.9L) inline six-cylinder engines Firing order: 1-5-3-6-2-4 Distributor rotation: Clockwise
Fig. 2: 232 cid (3.8L) V6 engine Firing order: 1-4-2-5-3-6 Distributor rotation: Counterclockwise
Fig. 3: 255 cid (4.2L), 302 cid (5.0L), 360 cid (5.9L), 390 cid (6.5L), 460 cid (7.5L) V8 engines Firing order: 1-5-4-2-6-3-7-8 Distributor rotation: Counterclockwise
Fig. 4: 351 cid W & M (5.8L), 400 (6.6L) engines Firing order: 1-3-7-2-6-5-4-8 Distributor rotation: Counterclockwise
Fig. 5: 6.9L diesel engines Firing order: 1-2-7-3-4-5-6-8

FIRING ORDERS NOTE: To avoid confusion, remove and tag the spark plug wires one at a time, for replacement. If a distributor is not keyed for installation with only one orientation, it could have been removed previously and rewired. The resultant wiring would hold the correct firing order, but could change the relative placement of the plug towers in relation to the engine. For this reason it is imperative that you label all wires before disconnecting any of them. Also, before removal, compare the current wiring with the accompanying illustrations. If the current wiring does not match, make notes in your book to reflect how your engine is wired. Fig. 1: 300 cid (4.9L) inline six-cylinder engines Firing order: 1-5-3-6-2-4 Distributor rotation: Clockwise
Fig. 2: 232 cid (3.8L) V6 engine Firing order: 1-4-2-5-3-6 Distributor rotation: Counterclockwise
Fig. 3: 255 cid (4.2L), 302 cid (5.0L), 360 cid (5.9L), 390 cid (6.5L), 460 cid (7.5L) V8 engines Firing order: 1-5-4-2-6-3-7-8 Distributor rotation: Counterclockwise
Fig. 4: 351 cid W & M (5.8L), 400 (6.6L) engines Firing order: 1-3-7-2-6-5-4-8 Distributor rotation: Counterclockwise
Fig. 5: 6.9L diesel engines Firing order: 1-2-7-3-4-5-6-8

With the vacuum line(s) dis-connected from the distributor and plugged up, the engine timing should be set at 4 degrees before top dead center idling at 650 rpm, and if it has California emissions then the ignition timing should be set at 12 degrees before top dead center while idling at 700 rpm. If the timing specifications listed on the vehicle emission label are different from these specifications then the specifications listed on the emission label are to take precedence.

Use a timing light to check the ignition timing, (and be sure that the timing light is connected to the #1 spark plug wire) and if the ignition timing is not to specifications then loosen the distributor hold down and turn the distributor until the timing marks move into position and are aligned to the timing specification, then tighten down the distributor hold down and then re-check the timing to be certain that the distributor did not move out of timing when the distributor was tightened down, then re-connect the vacuum line(s) to the distributor and re-set the engine idle back to where it was if it had to be changed. Be sure that the timing scale and marker down on the harmonic balancer/crankshaft pulley and the engine block are clean and they will show up well, and you can also mark them with chalk so the engine can be timed easily.

If you connect the vacuum line(s) to the distributor and the engine runs poorly then all of the vacuum line(s) to the distributor will have to be checked and then connected to their proper vacuum source.

If the ignition wires are leaking secondary voltage you might get a good secondary voltage shock if you touch the distributor to turn it. Let me know if you need help connecting and using a timing light, or if you require any further assistance.

Here is a firing order diagram to help assist you.

diaconnect the vacuum advance, and loosen the distributor hold down bolt just enought so you can turn the distributor, at idle turn dist, to advance mark on the harmonic damper to spec, either found on a sticker under the hood of from manual, need a timing light, tighten dist bolt ,

4.2L 6-Cylinder

1. Set parking brake. Shift automatic transmission to Park or manual transmission to Neutral. With A/C off, start engine and attain normal operating temperature.

2. With ignition OFF, connect an ignition timing light and a calibrated, expanded-scale tachometer.

3. Disconnect 4 " and 10 " Hg (CEC System) vacuum switch assembly wire connector (located at top of valve cover). Disconnect and plug distributor vacuum advance hose.

4. Start engine, increase engine speed to 1600 RPM and check ignition timing. Adjust timing to specification listed on Emission Control Information label (if necessary). Tighten distributor hold-down clamp and recheck ignition timing.

5. Turn engine off and remove timing light and tachometer. Connect No. 1 spark plug lead, if disconnected. Unplug and connect distributor vacuum advance hose. Connect vacuum switch assembly wire connector.

NOTE: If timing light has an adjustable advance control feature, turn control to OFF position.

Timing is set per the emissions tag under hood.

Ignition timing should be set at 10 degrees BTDC (before top dead center), with vacuum advance hose disconnected and plugged, engine idling at 800 rpm or less.

for 1991 geo metro 1.0 liter 3 cyl engine the timing is 6 degrees before top dead center. you will need a tachometer because the rpm must be 800 when you set the timing. also you will need to disconnect the vacuum advance to the distributor, and plug the hose to avoid a vacuum leak. (alternate method is to pinch the vacuum advance hose going to the distributor while you are setting the timing) Good Luck!

Ignition should be set to 5 degrees ( +/- 2 degrees)

Before setting ignition timing, be sure to disconnect and plug vacuum hose to vacuum advance unit on distributor.