Morris Minor Owners Club

A friend told me that we can reuse/recycle used sparkplugs.Any harm to the engine using used spark plugs?

The Haynes manual says check the plugs every 6000 miles and if worn excessively replaced.
Plugs wear by the electrodes being eaten away so there are no sharp edges.
This is most noticeable on the centre electrode.
I've got a feeling that which electrode wears depends on whether the car is positive or negative earth.
Also the insulation can break down but you need a special machine to see if this is happening.
Don't use plugs that are the wrong heat range for a Minor, that's another can of worms and could cause damage.

When using plugs on a s/v engine be careful to make sure the nose of the plug is not too long, especially if the head has been skimmed. The plug can touch the piston and close the gap or break the tip off

MarkyB wrote:The Haynes manual says check the plugs every 6000 miles and if worn excessively replaced.
Plugs wear by the electrodes being eaten away so there are no sharp edges.
This is most noticeable on the centre electrode.
I've got a feeling that which electrode wears depends on whether the car is positive or negative earth.
Also the insulation can break down but you need a special machine to see if this is happening.
Don't use plugs that are the wrong heat range for a Minor, that's another can of worms and could cause damage.

thanks markyb for your info..

mike.perry wrote:When using plugs on a s/v engine be careful to make sure the nose of the plug is not too long, especially if the head has been skimmed. The plug can touch the piston and close the gap or break the tip off

thanks for the important info.,mike