Thoroughly wash all the mechanical parts in petrol or paraffin and wipe dry with a clean non-fluffy rag. Check contact breaker points if applicable, and check distributor cap for signs of tracking, which is a thin black line between segments; replace it if this is obvious. Make sure the carbon brush is moving freely in the center of the distributor cap and replace it if it is worn or in poor shape. Should the metal portion of the rotor arm be badly burned or loose, renew the arm, although slight burning may be cleaned up with a fine file. Examine the fit of the contact breaker plate on the base plate and inspect the breaker arm pivot for looseness or wear and replace the plate if required. Inspect the centrifugal weights and pivot pins to check for wear, make sure the holes in the centrifugal weights are not oval and deformed, inspect and replace the springs if necessary. Check for fit of the breaker cam on the distributor shaft for play not to exceed 0.004 in (0.1 mm), and replace the breaker cam if it shows signs of wear or scoring. The play between the distributor housing and the driveshaft should not exceed 0.008 in (0.2 mm), if too great replace the bushes and, if too little, also the shaft. For driveshaft, replace old bushes by driving or pulling them out and pressing or gently tapping in new ones from each end with the felt lubricator between them with both the lubricator and bushes soaked in oil for at least 1/2 hour before fitting. The fibre washers in each end of the shaft should be placed adjacent to the housing and the end play in the shaft should be between 0.004 - 0.010 in (0.1 - 0.25 mm) which can be adjusted by changing the amount of spacing washers on the distributor shaft.