Obey,
As Chris says, a 50 4 stroke is about the max I would fit on a seahog. I owned one for 15 years, 12 of those years with a yam 30hp 2 stroke and 3 with a yam 50hp
4 stroke fitted.To say it flew with the 50 fitted is an under statement. The first thing you want to do, is check the transom on the hog, if it flexes in anyway it will need looking at! I had to rebuild the transom on mine prior to fitting the 50 4 stroke, water had entered in from the top of the transom and caused the ply to delaminate, basically no strength left in the wood. Sorry about the tale of woe. As Chris also mentioned the Tohatsu is a very good buy, because locally the Suzuki has a good name, and they are the same engine apart from the badge and price! Another twist to it all, is the Yams and Mercury powerheads in the larger 40hp to 100hp range are the same, but again the prices are different. I bought my latest boat as a package, and it has a Mercury 90hp 4 stroke which has carbs, if I was on the look out for a new engine, I think I would go for one with EFI because the fuel saving is even greater.
Cheers Steve