Spark Plug Gap for 420SL

[Chrono]

Hi

My first time on this board. Could anyone tell me what the plug gap for my 1988 420SL should be? Thanks for your help.

 

[jimmy]

All spark plugs should be pre-set these days. Whats the part number of the spark plug? NGK end theirs with the electrode gap, ie BKR6EK-11 is 1.1mm.

 

[Chrono]

They're Champion RN9YC

 

[jaymanek]

The 420/500 engine is v sensitive to gap so makesure you get it right... Not sure I remember what the gap is to be honest... Doesnt it say in the owners manual? Im sure it did for my 123, on that its 0.8...

Also, Bosch plugs are much better than champion if you havent already bought...

Thanks

jay

 

[Chrono]

Do you know the part number of the correct Bosch plugs please?

 

[guydewdney]

bosch w7dco
autolite 63
champion n9ycc
ngk bp6es

all 0.8 mm gap according to autodata

 

[Chrono]

Great! Thanks very much!