Can we get some specifics?
Basically what you are asking is a question of gear ratio of the outdrive. They should be matched. Some engines share gear ratios, so you need to figure out the gear ratio of your current outdrive and determine whether the gear ratio of that outdrive is compatible with the new motor.
Bullet list questions below for ease of copy paste.
- Model number of current outdrive / engine
- Model number for new engine
- Boat model & year (not exactly necessary, but I like to know)
Just something to consider: I agree with Lou, if you have the coin an upgrade is a wise choice. Just an option you may not be aware of if you are new to boats, they make brackets for the conversion to an outboard that are not crazy expensive.
I am going through a full rebuild on a boat that required the outdrive to be redone. I thought it was going to be cheaper but the unexpected items that needed replaced drove the cost way above budget to the point that I could have just upgraded to a used outdrive for a few hundred dollars more or perhaps the same price.
Single outboard brackets like the one below are cheapest. If you get a dual engine bracket, or one with a swim deck that will cost more. You just need to make sure the bracket matches the horsepower, so perhaps buy the bracket after the engine?
View attachment 33563
The other advantages that you can consider with this option are:
1.getting rid of the engine block from the inboard outboard frees up a great deal of deck space. You can put a bench seat or a live well where the engine is currently.
2.No more running the blower before startup.
3.If/ when it is time for replacement that is much easier.
4.Most people now would prefer to have an outboard setup. Things were different when your boat was built, inboard outboards provided more power and reliability than outboards in the 80s. Now outboards have gotten bigger and better, and because they are easier to swap out people just seem prefer them. So if you intend to sell this boat some day when you are ready to move onto something bigger or newer you will have increased the value of the boat somewhat.
5. because it is so much easier to change motors you can get an old one on craigslist and upgrade it in a couple years when it makes more sense. If you get the bracket that has the extra space for a trolling/ emergency motor then you can get an older engine without fear of being stranded on the lake since the backup/ trolling motor will get you back to the launch ramp.
6. No more removing the outdrive at the end of season to check bellows.
