Power is not an issue. A 3GM has plenty of power to run far larger pumps than needed. The power is the lure many DIYers first think about. Smaller diesels are sensitive to vibration. The trick is to build a bracket that doesn't act like a lever with a pump hanging off the side of the engine
intensifying the vibration 2 and 3 cylinder engines already create. Just a very slight offset that pumps easily create can make a well tuned diesel
bounce around on it's mounts like a bucking horse making the setup worthless and destructive to expensive equipment
. Usually Ecotech leaves it up to the owner to have his own mounting bracket made. They usually have suggestions on it's design depending on the engine build. There are side loading issues with a engine mounted pump that are never addressed on smaller engines. If your Yanmar
is new they will not usually warranty bearings if they find anything other than a recommended alternator
bolted to their engine. I don't want to get into any arguments with others that have engine mounted pumps that seem to work
fine. I'm just pointing out my experiance. There are about five major recognized builders of watermakers and several smaller manufacturers. They build many varied sized watermakers for hundreds of different applications anywhere from the 6gph to 100+gph, 12, 24, 115, 220 and 230Volt. None of the larger ones offer an engine mounted watermaker
for small boats. It should make you wonder why they are not all over the simple solution of just bolting on a high pressure pump.