1960's era mercury outboard hp 9.8 or 6?

[Scott53]

I bought a 1960's era mercury outboard.The owner said that it was a 9.8 hp.I just noticed on the base where the motor sits in has a 6 hp decal.The serial number is 1581255.On the serial number charts it could be a 1961 6 hp or a 1963 9.8 h On the powderhead there is a number 837-1903 also with the word LIGHTING on the cylinder part of the head.I've tried to check this out online with no luck.Any help would be appreciated.

 

[steelespike]

Re: 1960's era mercury outboard hp 9.8 or 6?

According to my info a 9.8 is 18.5 cu. in. with a 2 1/8" stroke.
A 6 is 7.2 cu in. and a 1 1/2" stroke. I would guess a 9.8 is about 70 or 80 lbs and the 6 about 50 lbs.
I think you could carry a 6 without much of a struggle the 9.8 not so much.

 

[Frank Acampora]

Re: 1960's era mercury outboard hp 9.8 or 6?

So use a pencil or screwdriver (or depth gauge if you have one), in a spark plug hole and measure the stroke. That will tell you for sure what engine you have.

 

[Chinewalker]

Re: 1960's era mercury outboard hp 9.8 or 6?

The Lightning block would be the 9.8hp. I believe the 6hp block said "Comet" on the side...