Who Needs Yamaha, Mercury or Evinrude? Like in Thailand, Malaysia and the Philippines, they only need, what we think of as, a lawn mower engine of any horse power, or if they are running a tourist boat and really have the financial resources, a 3 or 4 cylinder car engine. The engine is mounted on a gimbaled bracket so it can swing sideways 360 degrees and move up and down. But also the bracket has to balance the engine so it is easy to maneuver. With a little imaginative engineering, a long tube is attached to the engine, inside of which, the slightly longer prop shaft rides. Two bladed props are sold locally to fit common drive shaft sizes…..or a machine shop can make it fit. “Long Tail” is a common name for this home made outboard.
When not in use, the long drive shaft is swung forward to rest inside of the boat.
Some of the fishing boat engines run with no muffler or just a straight pipe. They can be heard like a Harley a half mile away. Obviously that fisherman says “What??!!” a lot, to his wife.
A similar sort of arrangement is used to make an inboard drive.
The pictures of the big car engines were taken of boats that never leave the confines of narrow fresh water canals. There is no room to really open up the rpms and get much more than an idle speed. It is like owning a Ferrari and never getting out of the city limits. The men who really work hard out on the ocean fishing, have the more practical engines.