How To Use A Dwell Meter To Set Points

How to Set the Timing With a Dwell Meter

by Chris Stevenson

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Many vehicles come with breakerless ignition points systems. Ignition points take contact points that open and close, according to the position on the distributor shaft cam lobe. The high and depression spots on the cam lobe govern the length of time the points are open and airtight, which sends a voltage signal to the spark plugs for firing. The open and closing duration times the spark to each cylinder. A vehicle owner can use a dwell meter to set his ignition betoken timing, according to industry's specifications, then synchronize his bones timing. The following instructions should only be attempted by experienced home mechanics.

Step ane

Place the vehicle manual in "Park" for an automatic and "Neutral" for a manual version. Apply the emergency brake and raise the hood. Do not work on a hot engine -- let it absurd somewhat earlier making the aligning. Expect at your distributor cap and determine if it has an adjusting window on the side of the cap. If it does, you lot will set the points with an Allen wrench. If non, remove the distributor cap by turning the two cap hold-downwardly springs outward with a slot screwdriver, or unscrew the cap with a Phillips screwdriver.

Pace two

Hook up the ruddy lead to a dwell meter on the negative (-) final on the ignition curl or roll pack. Refer to your owner'south service transmission if y'all are unsure of the gyre or gyre pack location and final position. Claw upwardly the other meter atomic number 82 to a proficient engine ground source. For the adaptable window distributor, fix the meter for the degree or "Dwell" calibration. Place an Allen wrench through the adjustment window on the distributor cap, connecting it to the aligning spiral.

Step 3

Instruct an banana to start the engine. Read the dwell in degrees on the dwell meter screen. Refer to your owner's manual for the correct dwell angle setting (i.due east. 30 or 32 degrees). Turn the adjustment screw in (clockwise) to increase the dwell, or out (counterclockwise) to subtract the dwell. Once the needle reads the right number, withdraw the Allen wrench and shut the engine off.

Step iv

Wedge the distributor cap away from the benefactor body, with the lesser facing upwards. This process works for the non-window distributor cap. Remove the rotor with a screwdriver, or by manus. Loosen the two screws that hold the points in place on the distributor plate. Loosen them only enough so the adjustment arm on the points move. Identify a slot screwdriver in the adjustment slot on the points and have your assistant turn the engine over. Read the needle on the dwell meter. Turn the screwdriver clockwise to increase the dwell, or counterclockwise to decrease the dwell.

Step v

Instruct your assistant to turn the key off. Tighten the ignition point plate screws. Replace the rotor by hand, or use a screwdriver to tighten in identify. Gear up the benefactor cap back onto the distributor and use the advisable screwdriver to refasten the screws or the pocket-size concord-down clamps. Refer to your owner's manual for the proper ignition timing of your engine. For case, it could be 8 or 10 degrees BTD (before top dead center)

Step half-dozen

Disconnect the vacuum line that attaches to the distributor vacuum accelerate diaphragm on the side of the distributor. Locate the notch on the crankshaft caster and the small metal timing tab on the front of the engine cake. Use a rag to wipe the minor lines and numbers clean on the tab and pulley. Utilise a socket, extension and ratchet wrench to loosen the distributor agree-down bolt, but only enough so you can movement the distributor with mild force per unit area.

Step 7

Hook upward the red pb of a timing low-cal to the positive terminal on the battery. Hook upward the negative lead of the timing light to the negative battery terminal. Place the timing lite wire clip on the number i spark plug wire (check your repair manual for its location). Take your banana start the engine. Point the timing light nozzle downwardly at the metal timing tab. Turn the distributor so that the notch in the crankshaft pulley aligns with your right degree number on the tab, according to your service transmission.

Step 8

Shut the engine off. Tighten the distributor hold-downwardly bolt with the socket, extension and ratchet wrench. Reconnect the vacuum accelerate line to the distributor. Unhook the timing calorie-free leads. You accept now set up the timing later on you have adapted the points for the proper dwell bending.

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