trade 80hp lower unit to a 85hp??

[fish4fun2]

I ate a couple of logs on my 1977 85hp lower unit. It looks like a big cat took a bite out of the dorsal fin a couple inches below the drain plug anyways i have a 1971 80hp spare motor i would like to swap lower units. Looking to find out if this can be done thanks

 

[WillyBWright]

Re: trade 80hp lower unit to a 85hp??

Welcome to iboats and go right ahead.<br /><br />I don't have the information at hand, but they might have different gear ratios. If you find that's the case, you can compensate with a different prop pitch. It would only be one prop size different if that is the case. But physically it will fit just fine. Do the water pump and give it some fresh gearlube.

 

[fish4fun2]

Re: trade 80hp lower unit to a 85hp??

Thanks for the information Willy i just was not sure it they were interchangeable or not, I should first drain the oil and see if there is any bad news comming out.