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Join Date: Sep 2005
Location: New Westminster, BC
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Absolutely the easiest Re & Re will be to replace like with like. Motor mounts, shaft alignment, prop pitch etc will all match. Problem arises when that motor is no longer available, then look for the closes match in terms of fit.
Moving mounts is not usually a big deal, but motors often have different mounting angles and/or limitations, different gearboxes have different exit angles, and most engine boxes leave little room for shifting things around to line up again.
Know the overall dimensions you need to fit into, V drive vs straight drive, overall height and width of the engines under consideration, spacing of the engine beds (easier to make it narrower than to go the other way). Even the weights can differ considerably for similar horsepower, though on a BCC that's not going to be a big issue.
The other thing to look at closely is the gear ratios. Changing that significantly will almost guarantee the need for a new or modified propellor. There is no 'standard'.
1984 Fast/Nicholson 345 "FastForward"
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)