Hello Wallypat and GLOMOD Grumpy

Thanks for that Grumpy, I suspect that first code digit should be a '7',
making this a 1976 machine.

The sparking plug will be a Champion CJ-8 or equivalent.

Wallypat, it's great to hear the machine is working really well. They
certainly 'hold their own' to any residential machine offered today.

For instructions as to 'set' adjustment, I have remastered a 45 Operator's Manual
that would have accompanied this lawnmower. See the History Forum record HERE.

Please let us know how you get on with this.
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JACK