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  #16  
Old 11-24-2006, 05:10 PM
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marshmat marshmat is offline
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Probably the biggest difficulty with fuels such as propane that are gaseous at ambient conditions is getting enough of the darn stuff in a tank to go very far. Natural gas (pretty much entirely methane), ethane, propane, hydrogen (the worst of them all for storage) are all a bit of a pain to compress/liquefy. Your range will be shorter than with the same size tank of a heavier fuel; in many cases though, the engine exhaust will be cleaner. In a boat, of course, if you have the space, the extra tankage is not a problem.
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  #17  
Old 11-24-2006, 05:23 PM
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Guillermo Guillermo is offline
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Quote:
Originally Posted by Dave Hawley View Post
So i have a cunning plan, I'm looking into converting the big gas V8s and other big drinkers to LPG, not taxed. I see no reason not to, large Land Rovers and Range Rovers have been doing this for years in the UK. My only worry is tankage, is it stable enough in extreem sea states? Anyone have facts about this?
We're testing that for fishing boats in Galicia (and not only for big engines, but also for small ones). In a few months we'll have the results.
Cheers.
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  #18  
Old 11-25-2006, 01:36 AM
Dave Hawley Dave Hawley is offline
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LPG for boats

Hi
Thanks for the info on the carb/injection side but what I'm really after is anyone who has practical experence of fitting tanks to sport boats or cruisers in the 25FT to 45FT area. I'm wondering if you have to fit rubber mounts to the tanks. When you see the huge LPG tankers they ship in perfect spherical tanks across the deck.

I'm wondering whether just strapping a couple of tanks from a gas heater is quite the way to go, there must be a better way to go for Joe Average without spending a fortune. Do you think this will work out cheaper than spending £10,000 on new diesel engines.
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  #19  
Old 11-25-2006, 04:14 AM
FAST FRED FAST FRED is offline
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Location: Conn in summers , Ortona FL in winter , with big dock & room for O'nite stop .
The downside is range , propane has fewer btu per gal than gas or diesel.

The upside is 130 octane fuel (if you can raise the compression ratio to use it) , and a clean burning engine.

The propane engines are so clean their service life is close to a diesels 5000 to 8000 rather than 1 or 2000 for gas.

Another HUGE advantage is the carb evaporates the fuel on shutdown , so varnish and crap in the carb from long sitting unused does not exist.

FAST FRED
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  #20  
Old 11-25-2006, 03:28 PM
Verytricky Verytricky is offline
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Petrol is liquid, Gas is well, gas, a thing that is not liquid. Dont understand the Americans - never will, not going to try now.


Right Now, in Southampton.....
Petrol is about £ 0.85
Gas is about £ 0.47
Diesel is about £0.90
Marine Diesel is about £ 0.31

So an oil burner is still definately the cheapest by far. Gas is OK, and there are nowdays many places to fill up. Petrol is just the worst. and guess what my boats run on
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  #21  
Old 11-26-2006, 04:45 AM
FAST FRED FAST FRED is offline
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Location: Conn in summers , Ortona FL in winter , with big dock & room for O'nite stop .
"Gas is well, gas, a thing that is not liquid."

Gas is shorthand for gasoline.

Bottled gas IS a LIQUID as stored and transported , and only becomes a gas upon evaporating in the tank before the regulator , or on Propane vehicles at the regulator feeding the carb.


So an oil burner is still definately the cheapest by far.

Depends how you amortize the diesel first cost and far more expensive maint .
$6000 for a 250 HP gasoine engine $ 20,000 to $35,000 for a 250 HP oil burner .
1000 to 2000 hrs from the first , perhaps in constant service 8000 to 15,000 for the diesel.

Rebuild the gasoline for $1500 the diesel for $5000 to $10,000.

Cheapest ,,?? Perhaps.

FAST FRED
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  #22  
Old 11-26-2006, 08:20 AM
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marshmat marshmat is offline
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Ahh, Fred, you gotta understand the Brits.... they have an irritating knack for using terminology that makes sense, very much unlike most Yanks and some Canadians
verytricky, it looks like you have the distinct advantage of not paying road tax on maritime diesel. We Canadians pay that tax (which, incidentally, has nothing to do with either roads or transit anymore) on all our fuels, including at the marina fuel dock. Unless you're the military or a farmer.
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  #23  
Old 11-26-2006, 09:30 AM
Verytricky Verytricky is offline
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I dont have to pay tax on my heating oil ( which happens to be diesel! )

I am a farmer ( well I live on a farm, and I grow trees.. ) So I get tax free heating oil and if the vehicles dont leave the land I dont have to pay tax on the engine fuel either.

All boat diesel is tax free in the UK. They colour it differently so you cant use it in trucks etc. My heating oil is uncoloured, whilst 'normal' road diesel is yet another colour.

Confusing?
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