Running on Gas. Help!

Bob, the heating fuel you refer to is not LPG, it is basically diesel.  LPG needs to be kept under high pressure in order for it to be liquid.  Otherwise you would need a monumental tank in order to keep enough gas for acceptable ranges.  Hence the reason why you need special fillers and tanks, and the LPG must be kept underground (regulations move fast in the UK, usually due to the EU)

Wombat

Originally posted by Phat Bouy AFAIK, farmers with very few exceptions (I stand to be corrected) may use RD legally away form the sea.

That's right; farmers and fishermen. And by an amazing coincidence, lots of MPs own agricultural land.

Yeah, but they've got those Avon Seariders. They have a flooding hull to stabilise them at rest so when you take off, you have to shift the water out before you can get onto the plane. It takes at least 2s plus a bucket load of fuel just to do that. That's each and every time and if you have several - it doesn't bare thinking about  

I try and avoid the Avons; too wet and heavy when at slow speeds. This changing weight (mass) of the boat seriously affects handling characteristics especially when you slow down and the hull floods. Unless you are very used to this, it is easy to plough into the victim you are trying to help. 

Another problem with them is that when they are trying to plane and the "nose is up", you can't see any swimmers or other obstructions in the water until the nose comes down

The Tornado or Humber RIBs are my prefered weapon of choice with a 50HP on the back - they go like scalded cats and get onto the plane at once. 

This brings me seamlessly back on topic by adding - How much weight will you add by converting to LPG and the associated tanks etc.. and how will this affect performance??

Hi combat wombat, sorry to contradict you on so many points , but that's what forums are for I guess.

LPG (liquefied petroleum gas) is not expensive to keep, does not require underground storage, it is kept under pressure though. Any of the bulk gas suppliers (Flogas, Countrywide, Calor and many more) will be pleased to supply a bulk tank of maybe 1000 litres capacity for a nominal annual rental dependant on gas usage. Portable tanks do exist, although it would be daft to buy the LPG from a road fuel supplier and pay 47p/lt duty on it, when as a lake user you don’t need to pay duty at all, and only 5% VAT . The bulk tanks come complete with an idiot proof filling nozzle, level gauge, and dispensing pump. Gas used by this method can be bought for around 30p/lt plus 5% VAT.

Domestic heating is regularly achieved using either diesel (heating oil) or LPG (propane) but the boilers and plumbing are quite different for each option.

Your figures for power and fuel consumption are way off too. Power is not affected so long as the conversion fuel metering hardware does not compromise air flow into the engine, many do. LPG is of a higher octane value than petrol. LPG has a marginally lower calorific value than petrol, but try measuring that on a boat!  Consumption using LPG is increased by as much as 25%, but this only means that you would reduce your range by that amount, and the benefit in cost of 30p/lt against petrol at 95p/lt is a bit obvious, (ok petrol is about 80p/lt if you get the VAT back) Hmmm.

All that aside… LPG is the fuel of choice for many ski lakes in their V8 chevy powered tow boats, and I recon if they suffered significant power losses they might not use it!