What engine?
Bob,
It's most likely an M25. I used a rubber bike tire tube, cut up, to fashion a "cushion" between the HX and the bracket. It sounds like your PO might have done something like that. It is NOT OEM. When we first bought the boat one of the "fitting out" suggestions was to have a bicycle inner tube on board to use for hose repairs. Never used it for that, but it does come in handy for other things!