1972 Mercury 800 80 Hp

[kjburr08]

Hi,

I do believe the motor is a 1972. The serial number is 3427373. I was wondering if someone could correct me if I'm wrong.

On to the bigger problem. I have a 1976 steury 16' boat. I am trying to put this motor (80 horse merc) on it. I have noticed that there is a sticker inside the boat that states the max horsepower is 60. I was wondering if it would be ok to put this 80 horse on it. I know its probably not a very good idea, or if its legal, but what are your opinions? I also have plates of 1/4" steel I could use if you guys think it would help.

On another question, I noticed the boat has a like ping pong ball on the outside by the plug. Have you guys ever seen these and how do you use it, because it seems as if you would need an inside plug, then when you get going you can take the inside one out to let water drain. I have no experience with this stuff so any info is appreciated.

Oh and one other question is when I went to change the lower unit oil it was kind of green looking, is this normal, and what oil should I be putting back in it?

Thanks

kenny

 

[Barnacle_Bill]

Re: 1972 Mercury 800 80 Hp

Yes its a 1972. As for putting it on that boat, its legal unless your state has laws against it. But an insurance company could take you to the cleaners if you were ever involved in an accident with it and they found out your boat was over powered. That ball takes the place of the drain plug. I've never used one so can't say much about them. Green looking oil probably ok, whitish looking is bad.

 

[puddlespoon]

Re: 1972 Mercury 800 80 Hp

ping pong ball type plug, yes i've had one. they float in and plug hole while sitting and roll out when throttling to let water run out and should float back in on decelleration(its centrifical force).sometimes they will leak through, if you can change to a plug, its better, i did. good luck

 

[Starppy]

Re: 1972 Mercury 800 80 Hp

You are asking for trouble by over powering it. Yes, insurance will throw a fit and may even refuse to cover you. The bigger issue is that the boat was not designed for that HP. The transom will be your biggest problem. It's old and already not as strong as it was new. On top of that it probably alredy has holes in it from the original engine which has weakened it further.

The other issue is weight. The back end will probably sit lower and the tub may not even drain properly. You may have issues with swamping in rough water or hard stops. There probably will be handling issues as well.

I personally like to stay below the max rating by 10% or more. If it's rated for 60hp I'd put a 50 or 55hp on it.