Fellow Golf buddy thought he was making a killing when he bought a 50 foot motor boat with twin cat engines in Adelaide off a friend. First shock was that ,according to him , fuel cost Adelaide/ Brisbane was close to $20,000!
I told him wind was free

Boat's already in Brisbane . He thinks he might have been to smart for his own good as it needs big dollars to bring it up to scratch

Time to buy a diesel Ute for his business :-) :-)

Crusoe said..
People who own 50ft motor boat soon learn that the word boat is actually spelt with 2 "T"s. (Bring Out Another Ten Thousand)

Oh geez, now you've done it ..... H2O will now be unstoppable

LooseChange said..

Crusoe said..
People who own 50ft motor boat soon learn that the word boat is actually spelt with 2 "T"s. (Bring Out Another Ten Thousand)

Oh geez, now you've done it ..... H2O will now be unstoppable

What was that? Two T.T's

LooseChange said..
If he's not in a hurry all he need do is to run it on one engine and alternate between one and the other to share the total hours. The speed difference between one and two engines is possibly not going to be as large as one might imagine.

Yes, running one engine at a time is an excellent recommendation. He should also make sure he runs at the recommended cruising RPMs, not any faster, else he'll kill fuel efficiency.

By way of comparison, here are some stats for my Lightwave 38 sailing cat which has twin Volvo Penta D1-30 engines (27 hp):

1 engine (cruising @ 2400 RPM): 6.5 knots @ 3 litres/hour
2 engines (cruising @ 2400 RPM): 7.5 knots @ 6 litres/hour
2 engines (full throttle @ 3200 RPM): 8.5 knots @ 14 litres/hour

Suffice to say, I rarely use more than one engine at a time and I rarely go above 2400 RPM.