Approx engine fuel comsumption

[ianmacaulay]

hi i am after changing my boat to a maxum 1800 sr3 with the 4.3 mercruiser engine but would like to know fuel comsumption first

thanks ian

 

[Whitelighter]

I would have thought some where around 1 litre per mile, provided you aren't flat out everywhere.

 

[ianmacaulay]

whats that in ltrs per hour

 

[Whitelighter]

With aplaning hull, from full planing to about 80% throttle MPG is about the same. In this case I reckon it is about 4-4.5mpg.

In terms of l/hr, depends how fast you are going. 20knts you will use probably 18-20l/hr, at 25knts 23-25l/hr and so on. Go more than 75-80% throttle though and it will start to drink a lot more.

All this depends on sea state, trim etc etc etc etc etc etc etc

 

[duncan]

about 2l per mile flat out - 1l pm as Jez suggests if lightly loaded, clean and running at about 14 knots

best o to go to a US boat test site and find the nearest example where you will get all the data you could ever wish for - in europe they don't tend to quote such detail so readily!

www.boattest.com?

 

[ianmacaulay]

thanks very much i think the 3lt mercruiser will be a cheaper option then

thanks ian

 

[Whitelighter]

Not neccessarily. Fuel consumption is linked to power. The more power the engine is using, the more fuel you will use. If it takes 140Hp to get your boat to do 20knts, it will take that power with either the 3.0 or the 4.3. The danger is that to get the same speed out of the 3.0, you might have to push the motor into that last 80%, which really supps the juice.

 

[duncan]

yes and no - cheaper to buy and possibly more economical but not necessarily in gallons used per mile travelled.

because of the drag issues associated with planning hulls and the fuel consumption curves associated with highly tuned petrol engines these are not linear at all and your 3l may have to have such a higher throttle setting at a particular speed that it's using more fuel for less speed!

having said that from boats I have known in the 1800 range it's right between the 2 engines - ie either will do the job (unless you plan to load up the boat fully every trip in which case the 4.3)

boattest.com does have a repost and stats on the 1800sc3 - it's free to register and access your first 5 reports. this will give you definitive data and good specific advice.

 

[ianmacaulay]

great point there thanks never looked at it like that but very true

i just looked at that boat test web site but have to pay to read the reviews

thanks

 

[ianmacaulay]

so what would yous advise me to get i will have bout six people on it and will be using it for bit of water sports and also some travling round to private bays and that

thanks ian

 

[Whitelighter]

I would suggest that with the weight of six people and to do water sports you should really go with the 4.3

Fuel consumption will be marginally more if anything during cruising, and with the extra weight (and for towing skiers/toys) you will really use the extra power.

 

[ianmacaulay]

and what sports boats at 18" with the 4.3 lump are highly rated



thanks ian

 

[Whitelighter]

phew. Now you are asking.

To be honest, Maxum have a good name, but probably worth consiering Glastron also. Essex Boatyards now deal in these, and the back up is very good. It all depends on your budget. I don't think Monterey do a sub 21 footer, but if they do they are worth considering.

At the upper end of the US market you have SeaRay. I have never seen where the extra money goes with these boats over a Maxum etc.

Also worth checking out Bayliner. You can say what you like about their bigger stuff, but sports boats are where they cut their teeth, and they still do them well. Other than the Maxum, and without giving you an exhaustive list, I would look at:

Bayliner 205

and

Glastron GT 185

 

[ianmacaulay]

well second hand for around 9-10k and need to be 18" max because at that size overall lenght on trailer is about 22 " and i store in my garage and any longer i will not be able to get the swing on it to get it in

thanks very much

ian

 

[gjgm]

3.0 will be underpowered with that many people on board and watersports, but the difference in fuel running between 3.0 and 4.3l should effect the decision.
Lots of USA sportsboats about; its quite easy to see what you are paying for.. better finish, better design, better fittings. And the more expensive ones tend to stay looking better for longer.
Take a copy of MBM and look at the new prices for 18ft sportsboats.. you d expect there to be a good reason, and the differences will continue in the second hand market. Quite what price/quality bracket you like has to be your decision, as its very personal. BTW Regal hulls are supposed to produce a bit more wake, so that might be what your after for wakeboarding or ringo time.
If waterskiing, its worth looking at where you might do that. Open sea isnt very practical, and most sheltered areas are often reserved for ski clubs- just check around b4 assuming you can find a good location locally- I found it surprisingly hard.
Do a quick search on sportsboats.. its a common question, so maybe you can glean some ideas from other threads.