Hi ian. Re the prop I was not performing well with my mariner 150 hp V6 2 stroke and spoke to dealer who said the correct pitch would be 19 but maybe that was because of the load I am not loaded with divers and all their garb but i still think its the same engine. Why not speak to Turbo diesel on here he maybe able to help. Yes the diaphram was the fuel one within the block two summers ago I could statr idle but when asked to 'go' I would not get above 2500 revs just leveled out it was the 'D' worth a check.
Hope you get to the bottom soon.
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