Jaguar Repair: 85 jaguar xjs v-12, jaguar xjs, condenser

Question
ok you recommended putting a condenser on my fuel pump feed wire to stop it from breaking the relays I've called parts stores and they dont what kind to give me do you have something I can tell them I need.

Answer
Melanie, I said if it is burning the contact points to try a condenser, you need to open up a failed relay first to see what is failing on the relays first. Even then it is a guess as to what size condenser and if it were mine and it was burning the contacts I would try any condenser from a pointed ignition system and it don't matter which one.

A condenser tries to bleed off high voltage that is left over in a coil when it discharges and that is a guess as to what value is needed so the same is true if there is voltage back feeding from the coils in the armature of the electric motor in the fuel pump. When any electric motor is turned off it coasts a little and becomes a generator and that voltage tries to jump the small gap in the contacts of a relay that connects and disconnects it. All of this tends to cause a spark at the contacts in a relay. You don't have the equipment to measure what microfarad value is needed so it is a guess but often a close guess works.

Tell them to give you any 12v pointed ignition system condenser and try it. They are not expensive.

Howard