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Overview

Breaker points adjustment

Model years: 1945, 1946, 1947, 1948, 1949, 1950, 1951, 1952, 1953, 1954, 1955, 1956, 1957, 1958, 1959, 1960, 1961, 1962, 1963, 1964, 1965, 1966, 1967, 1968, 1969, 1970, 1971, 1972, 1973, 1974, 1975, 1976, 1977, 1978, 1979

Model: Volkswagen Beetle / Super Beetle convertible and sedan (also known as: VW Super Beetle, SuperBeetle, Bug, Type 1, Type I, Coccinelle, Vocho, Kaefer, Käfer)

Difficulty: 3 (1=adding air to the tires, 10=rebuilding the motor)

Time required: 10 minutes

Tools: .016" Ignition feeler gauge Medium size flat head screwdriver 19mm or 21mm box-end wrench (whatever fits your generator/alternator nut)

Parts: None

Breaker points (also "contact points" or "points") are used in the ignition system as the physical means to trigger the firing of the spark plugs. They are part of the primary circuit of the ignition coil. When they are pushed open (by the rotating distributor cam), the primary circuit is interrupted. This causes a very high voltage in the secondary winding of the ignition coil which is immediately discharged by arcing across the spark plug gap to ground.

The breaker points are positioned inside the distributor such that each of the four lobes of the distributor cam periodically contacts the cam follower (typically a small block of nylon) as the engine turns. When the cam presses on the cam follower, the points are opened; once it rotates past the cam follower, the points return to their closed position.

The condenser is physically a small silver canister attached to the outside of the distributor body. Electrically, it is a capacitor wired in parallel with the points. As the points open, the condenser mitigates pitting by giving the current in the primary ignition circuit a path to travel without arcing between the faces of the points.

Dwell angle is the number of degrees in distributor rotation (1/2 crank speed) that the ignition points are closed. By the changing the ignition point gap, you are also changing the dwell.

This article focuses on adjusting the position of the points relative to the distributor cam, which affects the timing and duration of the opening and closing.

NOTE! The two faces of the breaker points must be smooth and parallel to get a proper gap measurement. If they are not, replace them (typically $3 to $6). If there is notable pitting on the faces, the condenser should also be replaced (typically $6 to $10).

Contents 1 Overview 2 Preparation 3 Step 1: Remove the distributor cap and remove the rotor. 4 Step 2: Rotate the engine clockwise to put the highest point on the distributor cam lobe under the Ignition Point Rubbing Block. 5 Step 3: Check the gap with a .016" feeler gauge. 6 Step 4: Adjust the ignition point gap. 7 Cleanup / next steps 8 Related links 9 About this article

Preparation

• Put the car in neutral and chock the wheels or set the emergency brake.

Step 1: Remove the distributor cap and remove the rotor.

Removing the distributor cap. Use the screwdriver to carefully pry off the two retaining clips which secure the distributor cap. Leave the wires connected, but move the distributor cap out of the way. Then lift the rotor straight up and off its shaft.

Step 2: Rotate the engine clockwise to put the highest point on the distributor cam lobe under the Ignition Point Rubbing Block.

Cam lobe maximally positioned against rubbing block on ignition breaker points. Using a wrench on the generator/alternator nut to rotate the engine by hand (via the generator/alternator belt). Attach a wrench to the generator / alternator pulley nut. With the transmission in neutral, rotate the wrench (and consequently the engine via the generator / alternator belt) until the highest point on the distributor cam lobe is against the Ignition Point Rubbing Block. It acceptable in this instance to position the point rubbing block on the cam lobe by rotating the engine either clockwise or counter-clockwise direction since these measurements are not affected by the "play" introduced into some parts of the engine by rotating different directions.

Step 3: Check the gap with a .016" feeler gauge.

Feeler gauge inserted to check the gap between contact points. Insert the .016" feeler gauge into the gap between the contact points. The feel of this should be "barely perceptive of the friction on each side of the feeler gauge."

Step 4: Adjust the ignition point gap.

Gap adjustments being made. Loosening the hold-down screw. Adjust by loosening the hold-down screw and moving the point faces closer or farther apart to achieve the .016" gap and feel required. Tighten the hold-down screw and re-check gap. Tightening the hold-down screw often moves the point adjustment. Re-checking of the gap after the last tightening is recommended as it may take several tries to get the gap just right. WARNING: Damage may result! Overtightening the hold-down screw can strip the threads in the distributor.

NOTE! You can also check your work by measuring the dwell angle. Dwell is read with a dwellmeter usually on a running engine. The correct dwell angle indicates the correct ignition point gap. The correct dwell angle for the air-cooled VW engine is 44 to 50 degrees. This corresponds to an ignition point gap of .016" to .017".

Cleanup / next steps

Replace the distributor rotor and cap.

Related links

• Engine and clutch (stock)/Static ignition timing
• Ignition timing on Wikipedia
• Breaker points on Wikipedia

NOTE! For reduced maintenance, the stock contact breaker points can be replaced with a Hall effect sensor.

About this article