What do ignition condensers do
The aim is to choose a capacitor such that, while the CB is opening and the distance between its contacts is increasing, the voltage across the capacitor and therefore across the CB never exceeds the breakdown voltage of the air between the CB contacts. If that is done, then an arc and consequent energy loss between the CB contacts is prevented.
The choice of the capacitance value is important. If it is too small, then arcing will arise at the CB contacts. If it is too large, then in addition to slowing down the rate of change of the voltage, it will also reduce the maximum voltage that can be attained so that it may be insufficient to cause a spark to be struck at the sparking plug. It should also be borne in mind that the capacitor needs to function satisfactorily over the whole speed range of the magneto.
Brightspark Magnetos Ltd disclaims responsibility for any errors in the translations. Regrettably, some Acrobat. Brightspark Magnetos. Magneto parts. Magneto services. Magnetos for sale. Online shop. High voltage can be caused from high voltage setting of the regulator or high resistance in the charging circuit or the third brush set too high. On third brush generators too small a gap at the points allows the points to stay closed longer resulting in the average current being high enough to allow the points to burn rapidly.
Contact pitting results from an out of balance condition in the system which causes the transfer of tungsten from one point to the other so that a tip builds up on one point and a pit on the other. The direction in which the tungsten is transferred gives an indication for correcting the situation. If the tungsten transfers from the negative to the positive point one or two corrections may be made. Increase the capacity of the condenser, shorten the condenser lead, separate high and low tension leads between the coil and distributor, move these leads closer to the engine block.
The condenser is a small electrical device connected across the contact-breaker points in the distributor. It helps to give a crisper spark at the plugs and also retards erosion of the contact-breaker points. If the points are badly eroded, and a general ignition check See Checking the high-tension circuit has eliminated other causes, suspect a faulty condenser. The condenser may be fitted outside the distributor, or inside on the contact-breaker baseplate; on a few cars it is fitted into the wiring somewhere near the distributor.
In most cases it is easy to get at, but on cars with poor access you may have to remove the distributor See Removing and refitting the distributor. A magnetic screwdriver, or a dab of grease on a screwdriver blade, is useful for fitting small screws. Replacing the condenser, which is mounted internally, is simple; but with the earlier type of contact breaker take care to reassemble th terminal post correctly.
Unclip and remove the distributor cap. Unscrew the terminal-post nut. Lift off the plastic insulating washer and the leads to the points and condenser.
Remove the screw holding the condenser to the baseplate. When reassembling the distributor, be careful to fit the leads underneath the plastic insulator.
Unclip the cap on some AC Delco types the cap is held by screws and remove it.