springy

Yes the leather cup washer - very like the one in a bicycle pump, as has been said, starting from the retaining nut, next a smaller solid (brass) washer inside the cup, then the cup washer itself and finally there should be a larger washer behind the cup, smaller than the OD of the cup but only slightly. The cap nut should not have a seal as that is where air is drawn into the pump body on the up stroke, passing by the cup, to then splay the cup and be forced through the foot valve into the tank. springy

Sometimes that sort of pump requires quite vigorous operation to gain enough pressure to properly splay the washer and form a seal. springy

When the float in the regulator closes the needle valve the back pressure prevents the pump from pulsing, I haven't explored inside the little pumps typically used now but I suspect they are similar in operation to the SU electric fuel pumps as used on thousands of Austin Morris cars & early Land Rovers - when the needle valve in the float chamber is closed pressure inside the pump holds the diaphragm back against a spring which prevents the contacts closing and therefore the pump cycling. When the needle valve opens spring pressure forces fuel from the pump, closing the contacts and energising the pump for another stroke. That being said all (3) of the refleks stoves i've played with have been gravity fed, one from a dedicated tank and two fed from the main diesel tank. springy

Dorman 3DA https://www.ebay.co.uk/itm/Large-Air-Cooled-British-Marine-Diesel-Engine-Dorman/153249997979?hash=item23ae69649b:g:v4QAAOSwww9b4piP:rk:36:pf:0 springy

I've also used Trefolex, Rocol, and a brown snot which I'm desperately trying to remember the name of -just had a quick google - Temaxol, though usually based on availability rather than a "best choice" and, in the absence of other alternatives, cooking oil. Any lubricant is better than none. springy

I've used mostly Starrett Bi-metal & found them to be pretty good, but as rusty said slow speed & lubrication. springy

If you have a Paloma or other instant water heater it will also need to be drained - the coil is very vulnerable to frost damage. springy

If its only for the shower then fit a Gulper, has to be switched manually but far less likely to result in a bilge full of water than a float box. beaten to it by mrsmelly springy

2 stroke engines which use ports uncovered by the piston are "direct reversing", for marine use they usually have symmetrical injection timing and "don't care" about their direction of rotation, not sure about other applications such as field marshall or lanz tractors. 4 stroke engines rely on half engine speed opening & c;losing of valves and the timing of those valves determines rotation. The ability to change the exhaust cam timing relative to the inlet cam timing (IIRC) allows a 4 stoke "reversible" engine. springy

Is it possible to drain the calorifier & then pressurise with air (being careful not to over pressurise) - you may then be able to use a liquid leak detector by bubbles to locate the actual leak ? springy

IIRC a "woodburner only" will burn its fuel on a hearth - no grate, - mine has a layer of firebrick, coal (& derivatives I presume) needs a grate to provide bottom air to maintain the burn, many multifuel stoves have an adjustable grate which can be virtually closed off for wood only. springy

Industrial HA2 https://www.ebay.co.uk/itm/Lister-HA2-Electric-Start-Diesel-Engine-19-HP-1500-RPM-Runs-Perfectly/352462963116?hash=item52106e01ac:g:yUEAAOSwHShbng9i springy

Is that just a vent, ? It looks rather like the exhaust for the gas flue for a three way to me. springy

If they are calor bottles then they are a 6Kg fill on Propane versus 13Kg, or 7Kg Butane versus 15Kg, The gas is also proportionally more expensive. In addition they seem to have changed their rules on exchanges between sizes slightly and to swap a 13 for a 6 you should have to cash in your 13 and take a new agreement (£40) for the 6Kg. On the other hand they will give you £7.50 each for unwanted bottles regardless of size. springy

I'm pretty sure this is a factory marine engine. springy