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Collection, Preservation and Display of Old Lawn Mowers

Spark plugs !!!

My god, what a work up .....   its never simple ...


I can find 11 different spark plugs all with different part numbers all claiming to be for my mower ...

So they must all be different yes, as otherwise they would have different part numbers ...


So PLEASE can somebody tell me the difference between these champion plugs as they are all apparently for my mower.

J8J - RJ19 LM - RN11 YC and CJ14   (there is a few others but lets start with these)

and NGK are listing:

B6S - B5HS - BR2LM -

It must matter what plug goes in ...  they cant all be right ..


I just want a plug for my MK4 Ransomes marquis

and 1 for an Atco commodore i'm working on ..... it cant be that difficult !!


I bet nobody out there knows either ! smiley





wristpin Mon, 30/07/2012

How much is the bet?!!!!!

If your Ransomes has a BSA/Villiers Sloper engine  you nead the NGK B5HS - a long reach plug. Original spec would have been a Champion  N8 which probably has a new number now!

TheJ8J, RJ19LM,and BR2LM  are all short (3/8")  plugs and unless you are ultra fussy are all more or less the same spec - certainly as far as your Atco Commodore is concerned! All pretty compatible with Briggs and Stratton side valve (L-head) engines.

The RN11YC is a long reach plug commonly found in Briggs and Stratton OHV engines.

CJ14    - NGK equivalent is the BM4A found in among other things, a lot of older Hondas



Mike Mon, 30/07/2012

Brilliant !!   .. thank you smiley


I shall get on and order some ...  I'm a happy bunny now !


wristpin Mon, 30/07/2012

Just added some pdfs from old Champion and NGK catalogues - enjoy!!

Mike Mon, 30/07/2012

... and thanks for the plug info pictures, very helpful .... I have saved myself a copy of them for future panic attacks !!   smiley


All the best