Before I became interested in Scott Atwater motors, I was collecting Mercury Dockbusters and rebuilt a couple of them. Concerned that I wasn’t spending my money as fast as I could, I started picking up Scott motors, parts, and literature. Now that helped crush the bottom line, at least until I figured I’d have enough parts and motors to last me till I closed the garage door one last time.
Wouldn’t you know it, a friend of mine just bought a Dockbuster and I didn’t even know he was going to do it. One of those couldn’t pass it up deals. It looks in great condition. Only problem, no controls. He thought they would easy to come by.
Luckily I have over a dozen of the Mark 75 controllers . I seem to remember there were two versions of them and it had to do with how and when the choke and pilot light operated. Because of that there some wiring changes inside the controller. I have the factory manuals and diagrams, but they don’t show clearly what he difference in wiring is. I can’t even find where the choke switch is unless they are combined with the forward and reverse switches.
I have enclosed pics of the two different control sticks, and you can see that one allows the button to move fore and aft and the other goes straight down. The one with the oblong hole seems to have a two stage action, one just for the starter and one (pulled back?) for both starter and choke. The other goes straight down, first engaging the starter? and then another stage for the choke just below. My guess is the latter was a safety improvement. I also believe the pilot lights may work differently.
I would prefer to give him the safest set-up, but I can’t remember which is which. I believe it was described pretty well in the operators manual, but I can’t find the one I had.
I would appreciate if someone that had one would send me copies of those pages. Thanks.
Don