Circuit Breaker

Check circuit breaker advance flyweight action by moving cam in direction required to advance weights to their fully extended position. Then release the cam and see if springs return to the fully retarded position. Correct causes for faulty action by cleaning and lubricating shaft, cam and flyweights and re-

210 (Advance breaker set-up it covered for those using eorly engines.)

placing weak springs.

Be extremely careful to avoid excessive lubrication. If too much grease is used, the excess is apt to get on the contact points and cause them to burn.

For maximum operating efficiency it is recommended practice to replace circuit breaker points when pitted, burned or worn excessively.

The condenser (4) is a relatively long life part and will not require frequent replacement. However, if the condenser is suspected of being defective simply replace with a proven new condenser and note whether engine performance is improved. A condenser that is defective will have either an open or short circuit. An open circuit will be evident by excessive arcing at breaker contact points and a shorted circuit will have no noticeable spark at the contact points.

Examine the circuit breaker base pivot stud (13) for wear or damaged condition. Try circuit breaker base (10, 10A or 10B) Fig. 5F-2 on stem, (22, 22A, 22B or 22C) for free turning, but not loose fit. If base has too much clearance on stem, the circuit breaker point gap will vary as the base is shifted for spark control. If base is found excessively worn or damaged in any way, renew it.

Examine the coil to circuit breaker low tension wire (12 or 12A, Fig. 5F-2) for brittle or cracked insulation and broken strands and replace if defective. Inspect circuit breaker wire stud insulator (15) and fiber washer (13) for brittle or cracked condition. Unless inspection shows insulation defective, it is not necessary to remove stud, insulator and washers.

Examine cam advance mechanism on automatic advance circuit breakers to see that flyweights (26) move outward freely and springs (27) return them inward against stops. Check for looseness of cam (24) on spindle (29B or 29C) and wear on sides of flyweight (26) ears which engage slots in cam. Check springs (27) and replace if stretched or distorted. To disassemble mechanism pry clips (25) from grooves in pivot pins on stem plate (29B or 29C). Inspect teeth or worm gear (31) for excessive wear and damage. Check the amount of end play and side play of shaft (29, 29A, 29B or 29C) in stem. End play in excess of .008 in. or excessive side play of shaft in stem bushings will affect ignition timing and also allow oil from cam gear base to enter breaker assembly base to contaminate ignition points.

If renewal of shaft or stem parts is necessary remove pin (30) from gear and lift or press circuit breaker cam shaft from gear. Withdraw cam shaft from base. If bushings have excessive wear, timer stem assembly can be replaced or stem assembly can be rebushed by drifting out old bushings and installing new bushings. New bushings should require no reaming. When reassembling gear and breaker cam shaft use standard spacer washer (.062 thick), or thicker washer (.066 thick) or (.072 thick) to obtain a .001 ot .007 in. shaft end play.

When assembling circuit breaker shaft in breaker stem, always secure gear and spacer washer to shaft with new steel pin riveted in place. Rotate shaft to be sure it is free in stem.

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