tophatyachts.com

1. I recently inspected a TH MK1 with a diesel installation. I was surprised at how far forward the engine is mounted, taking up a lot of the sole space, is this the standard positioning of inboard?

2. Also recently inspected a MK3 which has two or three plastic screw type hatches, presumably ventilation hatches, in the sides of the cockpit, also one behind the kitchenette area to ventilate the stove area, is this common?

3. Same MK3 had an O/B in well but an integrated fuel tank in the boat. Is this common or would it be because the boat initially had a diesel inboard motor? Do most TH's with O/B only have the plastic 20lt type fuel tank, if so where are they secured?

1/ should be under the companionway steps.
2/ no, mine has 2 they screw off and a cowling screws on. (aftermaket stuff)
3/ mine (outboard in well) has plastic on a shelf in the cockpit locker with vents.
I would think if it has a well it wouldnt have come out with an inboard.

Good questions.
My boat had an inboard fitted at some stage and one would assume the inboard was the original motor and that the outboard was fitted later. I bought it with the outboard and surprisingly, the well in the cockpit looks original. Otherwise someone did an incredible aftermarket job. I also have the 'dish' that fits in the well to close it off if and when there is no outboard sitting in there.

The only remnants of the inboard are the rubber exhaust hose (now used to carry water from the electric bilge pump) and the old diesel filler on the side above the cockpit locker(it was leaking water into the cockpit locker every time it rained). Any diesel tank that had been there was removed prior to my purchase of the boat.

My boat does not have any of those screw in inspection type hatches, except for the one on the water tank in the cabin sole. So unfortunately the cockpit locker vents into the cabin. There was a hole between the cockpit locker and the port side quarter berth. I sealed it off, but petrol smells still get into the cabin when the boat sits on the mooring for days. The petrol fumes seem to get through the walls of the plastic tanks. Perhaps the fumes get out via the hose that couples to the outboard. I might try wrapping the hose end to check this out. The cockpit locker is not sealed off and air can move into the cabin by the route around the stern of the boat and along the starboard quarter berth (mark3).

I use a 12 litre red plastic petrol fuel tank which sits in the cockpit locker (no shelf, just on the floor of locker). I replenish the petrol using 5 litre red plastic containers and try to minimise the quantity of fuel on board (max 12 litres, except when circumstances dictate more is needed).

I have thought of getting a small solar panel and fitting a fan on the side of the cockpit locker. There is only a mushroom vent above the cooktop. Have seen boats with a hatch here and it is probably a good idea (light fresh air and spot for cooking fumes to get out.
regards, john

1. My diesel extends about 10 inches into the cabin and is covered by the engine cover/top step. My egine is, however, an old Yanmar 14HP twin and modern diesels are much more compact ( and lighter).

2. My boat has no openings from the cockpit to the boat apart from the companionway hatch and the port seat locker. I do have one mushroom vent near the mast step to ventilate the V-berth area. I like to have as few openings as possible in the boat.

3. Diesel fuel tanks are usually in the boat somewhere and are generally stainless steel. Storm Petrel has a 50 litre SS tank under the starboard birth.

Cheers,
Mark

I have a 20 l plastic fuel tank. It was in the cockpit locker when I bought Windchaser, just sitting loosely in there along with the battery. Instead of leaving it in the locker, I put it beside the outboard motor on the cockpit seat and lashed it in place. I take it off when not using it but I don't think I would like it there in full sun in summer up here in the almost-tropics (Rockhampton). I think a secured place in the locker might be okay or maybe if I cover it with something to keep some of the hot sun off.

3. There are construction rules these days (similar to LPG) to avoid the problems caused by spills, fumes and accident damage. Drainage, ventilation and shut off valves are specified.

The Racing Rules of Sailing (Blue Book) also have specific instructions regarding installations.

Top Hats were built before all this knowledge was wide spread so it is up to the operator now.

Tales (MkIII) has a 1 1/2 liter tank in the motor for trips less than one hour and a 15 liter plastic tank which I lash to the aft pulpit seat for longer trips

Regarding storage of plastic fuel containers in enclosed areas, some of the constituents of the petrol can permeat through the plastic even though the container does not 'leak'.

All the best,

Tom