I've managed to get hold of 2 spark plugs type KLG L777.
One has 3 earth points and the other has only 2.
I was concerned about the method of setting the gaps.
I dont want to dive in and start bending anything in case I break or crack something.
Austin A7 cars use the same type, and on their forum they suggest.
"Tighten the gland nut to secure gas tightness, reset the earth points E to .015—.018 in. To do this it may be necessary to bend each earth point toward the central electrode"
Surely it would be impossible to set the gaps exactly the same, so therefore, the spark will continually jump the closest.
Also the BSA M20 "Useful Data" section states, set the gap between .012-.018.
Would this measurement be for these types of plugs.
Thanks
Keith
people think that these multi earthed plugs spark on all 3 points at once they dont the spark will only use 1 earth at a time when that is burnt further away from the central electrode another on takes over that why the will do 50000 mile on 1 plug no special performance
I have recently added to my small collection of KLG literature and amongst them is an October 1934 dated booklet detailing the 5/- KLG - Effectively the L777. KLG had for years promoted their 2-piece 6/- K series and 7/6d KS series plugs and the high prices were costing them sales so they intoduced the three-piece L777s for sale at the 5/- price level of the competition. It seems that this plug which they claimed had a more restricted heat range was suitable for most standard engines. As I understand it, this was the recommended plug for KM and WM20s up until at least 1942.