Antares 7.50 adding a heater

[MGsailor]

I'm thinking of installing a planar (autoterm) heater this winter, they do a marine kit with all the essentials. But I do not know the best location. At present, I am thinking in the void behind the cubby-hole above the sink, this comes away with only 4 screws so access is easy. There is plenty of height to ensure the combustion air inlet/exhausts are more than 60 cm above the waterline, but the width of the space here here is a bit marginal. On the plus side it is easy to rout the trunking to feet level at the helm. Has anyone a better solution?

On another topic, I have the opportunity to buy a 5hp short shaft (17") auxiliary outboard. The 140hp Suzuki I have runs beautifully, has only done 550 hours, but I feel I should have a back-up. There already is a 4-position outboard bracket on the transom which is rated up to 9.9hp. Would 5hp be enough for the Antares 7.50?

I would be grateful for any views. I've been a sailor for 40 years but have finally moved into a motor boat for the first time!

 

[simonfraser]

you may need more width than you think, inlet and outlet ducting have a large diameter and dont bend that sharply

 

[oldgit]

Fitted a "chinaspacher" to a small Rodman 700 not that long ago.
Changed all the known dodgy bits for good quality parts,needed to buy some extra length exhaust pipe and extra warm air ducting.
Need careful planning when installing, remember you will need to get electric drill in there for securing fixings, holes for hull exhaust and into top of fuel tank.
Owner did not want to faff about filling little remote tank, even if we could find have somewhere to neatly hide it.