RE: Shelly Foss Tug Build 76 inch
The american Bosch are very good motors too. I tired to get some but they were out. Ebay is very limited on them too. They have not been made for years. If you go to a wrecking yard you might find them on the older 1960's and 1970's car wiper motors. The problem is that some of them have a adapter places on the face of them that are part of the wiper assembly and so they are not a clean motor. If you can find two of these at Loyalhanna then you will have a good motor to use in your tug. They are twice the size of the Pittman but that is ok since you will have more than enough hull to put them in. They work at lower speeds too since that is whata they were designed for. You may need to had a belt drive to make the speed of the prop more authentic though.
You are going to need the weight of at least three car batteries to get the hull to go down to the waterline. Build the tug light without any lead ballast so you can easily carry the hull where you want to take it. Biggest mistake I see is someone building these big boats and getting them so heavy that they need a small trailer or two people to load them into the water. That is what led shot weight packets from dive shops are for. I throw a few of them into the bottom of my tug for extra weight if I am just running one deep cell optima boat battery for weight.
Dallas