82 7.5hp evinrude help

Just inherited an 82 7.5 hp Evinrude, but no owners manual. Model E8RCNR, Ser #C7150972. Would like to know the following if possible:
1- proper fuel / oil mix
2- spark plug gap
3- gear oil type and capacity

Motor runs fine, just want to clean it up and do minor tune up. This is my first outboard and any info, help and tips would be greatly appreciated.
Thanks

Re: 82 7.5hp evinrude help

wlecome to iboats.

fuel 87 octane mixed 50-1 with TC-W3 outboard oil. brands are mostly alike, just meet the TC-W3 rating.

gap .030 use Champion plugs.

80-90 outboard lower unit oil.

read the TOP SECRET FILE.

Re: 82 7.5hp evinrude help

Thanks tashasdaddy, couple of more questions. At the end of the throttle handle there is an adjustable collar around the stop button with clicks every quarter turn. What does this adjust?
Do I fill the gear oil to top of filler hole or is there a capacity limit and finally, what and where is the Top Secret File?
Thanks

Re: 82 7.5hp evinrude help

The "collar" round the stop button is the idle speed adjustment. Turn it anticlockwise and yo'ull be able to shut the throttle a bit further. Turn it clockwise and you wont be able to shut it so far.

Takes several "clicks" to make much difference!

You fill the gear case via the bottom (drain hole) until oil flows from the top (level) one, using a squeezable bottle, or a pump that can be bought for the purpose. When full fit the top plug then quickly fit the bottom one.

You should always use new seals on the plugs.

The "top secret file" is the second one down in the Johnson Evinrude Index

BTW an '84 model holds 325cm? (about 11 fluid ozs I think) of gear oil. Yours prob. the same, not much different anyway.

Re: 82 7.5hp evinrude help

For the sake of sounding like an idiot, why is the gear oil changed from the bottom. Why not from the top like a car diff?

Re: 82 7.5hp evinrude help

It sounds daft but it is the way to do it. Tends to air lock if you don't and you might not get it fully filled.
The holes are a lot smaller than the ones on car diffs and gear boxes.