Older Yamaha 40hp

[sockjockey]

Am looking for help regarding my Yamaha 40b which appears to be from 1978. It is a 2 stroke twin with a single carb and although it runs well enough it is in need of a bit of love. I am struggling to find a manual either on line or in print for such an aged beast with all the stuff available being for 1984 onward engines? Anyone point me in the right direction. Thanks in advance. TimG Poole UK

[boats.net]

Are there any other numbers on the motor?

[sockjockey]

Markings are 40BE 676B sn 400951

Regards
Tim