Has your Spring Sprung?
The importance of breaker point spring tension should never be overlooked. It
should be considered equally important as the gap.
A breaker point with too little tension will bounce and cause ignition advance to vary and
thus cause premature power head failure. A breaker point with too much tension Will cause
premature point follower wear which leads to poor performance.
The method of checking tension is as follows:
1. Expose breaker point as outlined in appropriate service manual.
2. Connect one lead of test light to breaker point terminal screw and the remaining
lead to a good ground.
NOTE: Breaker points being
checked must be in closed position.
3. Switch test light to "ON" position.
4. Position tension indicator lever at center of area where breaker points make contact.
Note: Any spring loaded weight
measuring device can be used, (such as a fish scale) but care should be exercised
concerning it's accuracy.
5. With lever of tension indicator, force breaker points to open. When points
light will go out. Check ounce reading on indicator when this occurs and repeat test.
Second reading should repeat within (2) ounces of first reading. If not, repeat until
readings are consistent.
6. Readings should be within range specified for the particular point being checked as
shown on the chart which follows.
(These numbers are supplied as reference only, check your engine manual for exact
Breaker Point Spring Tension (In Ounces)
(2 cycle motors)
24-32 (Battery or Battery C-D)
(4 cycle motors, All horsepower's)
Several model Distributors could be used for any one model year engine so verifying
distributor type is the first step. There usually isn't much difference in spring
pressure, from manufacturer to manufacturer, but look for a published specification in
your owners manual.
The average specification is 20-30 inch pounds.