would it pay to buy old boat motors and overhaul them?

[HarborRat]

I've made plenty of money buying non-running small outboards...25hp and less, getting them running and selling them. They can be bought under $100 and sold for $300-750ish, usually with only minimal cost in parts, if any.

Once you go bigger than 25hp it is not worth it. Too heavy to pick up, to heavy and difficult to mount, and the bigger boat owners want newer more reliable engines. Plus most small motors are tillers and self contained. Bigger motors need matching controls and in some cases matching wiring harnesses. Small motors you can clamp on a skiff, test it out, then remove and sell after trial if needed.

Start "small" and you should do ok.

[pdxMIKEpdx]

What HarborRat said exactly!

One problem you are going to have is finding parts for the older outboards that you can pick up cheap.

Plus, in this day and age, nobody wants to troll with a stinky, noisy, plug fouling two stroke.

[sunsprit]

Originally Posted by pdxMIKEpdx

What HarborRat said exactly!

One problem you are going to have is finding parts for the older outboards that you can pick up cheap.

Plus, in this day and age, nobody wants to troll with a stinky, noisy, plug fouling two stroke.

This ^^^^^^

plus additional concerns:

1) the two-stroke motor fuel economy is only about 1/3-1/2 that of 4-stroke motors. In a day's use, that can be a big difference in how much gas you're using. Back in the days of 2-stroke 7.5 HP outboards, we used to go through a 5-gallon fuel can every few weeks for the auxiliary on our sailboat. When we changed over to a 9 HP Honda, it took us most of the sailing season to use that much fuel. And the 4-stroke engine started at the slightest tug of the starter rope where the older 2-stroke outboard always required multiple tugs and fiddling with the throttle/choke settings to get it to run.

2) many lakes now have emissions control on their water; ie, you cannot leave an oily trail behind your passage. Many 2-stroke outboards, even when tuned to the best they could be and using 50:1 mix, will still leave a noticeable trail of oil on the water which is no longer tolerated.