Bulk LPG Tank's

[saltwater_cowboy]

I'd say your running on the rich side doing 160L a day even with 1200lbs and 4 people. What LPG system have you got? Might be time for a tune if your doing that much fuel. The fully sacked air nautique we run won't use that and thats with 2000lbs of ballast.

It's possible to fit a change over switch and run a couple of fork bottles at the same time as the main tank.

For the amount you do I'd look at buying my own tank. Assuming you have storage for it (can't just put it anywhere) you'll end up paying 25p a litre instead of around 40p out of bottles.

The other option is get a transfer pump at around £200 and pump the LPG from 47KG propane bottles (the big tall orange ones). 47KG is the best part of 100L so two of them would cover your fuel for the day.

[rossl]

By a day i mean 8 hours straight, so 20L per hour.

I have check out on the net and i have found:

Tige 2100V "Riders Edition", with Merc 315HP 350 Chevy turning a 13x13
25L per Hour

Old MasterCraft used 8 gph
30L Per Hour

17' foot bayliner with Mercruiser 3.0 5gph
18.9L per Hour

I thought our 20L per hour was good, what do the other boats out there get?

rossl

[saltwater_cowboy]

Air nautique on LPG approx 2000lbs of ballast around 60L in 4 hours.
19ft mastercraft on LPG approx 1000lbs ballast around 45L in 4 hours.
22ft maxum vdrive on petrol (soon to be LPG) approx 1500lbs ballast 60L in 4 hours.

Driving style and the amount of fallen riders will affect it a lot. A set with say 6 falls in 20 mins will do twice the fuel of a 20min set with no falls.

[rossl]

Our boat is about the same size as a 19ft mastercraft and you get 45L in 4 hours!! What kind of tunning can you do to improve fuel usage?

ps. The engine is a indmar 351 v8, has had 2 brand new heads fitted just before winter, so have not ran them yet.

[saltwater_cowboy]

I've now sold the MC but I could get 2 days riding from a full tank (100L). We are limited by tides so normally 4 hours would be an average day. We had a fat seat approx 600lbs and normally 4 people of more.

Get someone savy with LPG and american engine knowledge to have a look over your system. My guess is your ignition timing is set standard for gasoline. You can advance by 6 - 12 degrees for LPG before you get any problems and that will make a huge difference to your fuel useage.

For example a mate has a 3.9 discovery same as mine. He runs dual fuel (either petrol or gas) and only gets around 12MPG on LPG. I run just LPG in my disco and have my ignition advanced by 10 degrees over standard and I get around 19MPG. Of course if I ran that ignition with petrol it would pink and burn out valves but not on a slow burning fuel like LPG.

Also what LPG system is it? Most marine systems rum IMPCO equipment but there is a big difference in economy with different vaporisers and mixers.

[rossl]

Think it is a IMPCO system , will check next time I am @ the boat, I think the boat was from West Midlands Water Ski club, they traded it in to TVSKI in datchet where we bought it from, the boat was in TVSKI end of last year for new head's and valves etc, not sure if they would have tuned it as part of the work as they had the whole top end off. As I said the 20L per hour was from last season, it may be better this year after all the work it's had done.

cheers
rossl