Cruise Craft 575 Outsider fully loaded!

[Gotty80]

I'm new on here sorry if this is covered somewhere,

I've got a 2003 Cruise Craft outsider i picked up with a F115 Yamaha which I've recently upgraded to an F150xb.
I'm not getting as good economy as yet from the new motor and i was really hoping to get equivalent if i could.

Im carrying 4 blokes, full fuel, fishing gear, ice, lead etc... its fully loaded and i travel 50 nautical mile each way.
After last trip out i wound her out fully trimmed in the river and its making 5500 revs and that was with 100 litres fuel used.
14-1-4 x 17p Reliance prop is apparently the lowest pitch the dealer can offer me.
motor is on the third hole from the top, not sure if thats right.

Anyone else with this combo carrying a big load?

cheers
Gotty

[Gotty80]

What props are other guys running with this combo?

[Duckfish]

Think that is about right. I've got a Haines Hunter 565LL with a Merc 150hp Four swinging a 18" prop wot about 5300rpm. Getting about 1.6 klm per litre and carrying a similar load. A days trip from Manly to Deep Tempest and back will use about 80 odd liters of fuel
Duck

[inveratta]

snap.....565L with 150 merc 4 banger..here are some figs from a test somewhere..not mine




PERFORMANCE – ECONOMY
3.6 l/ph @ 1000rpm
5.4 l/ph @ 1500rpm
8.6 l/ph @ 2000rpm
11.7 l/ph @ 2500rpm
14.3 l/ph @ 3000rpm
18.1 l/ph @ 3500rpm
24.1 l/ph @ 4000rpm
31.4 l/ph @ 4500rpm
38.6 l/ph @ 5000rpm
52.0 l/ph @ 5500rpm
53.5 l/ph @ 5600rpm (WOT)

[inveratta]

[QUOTE=inveratta;1628976]
snap.....565L with 150 merc 4 banger..here are some figs from a test somewhere..not mine





PERFORMANCE - SPEED
4.2kts (7.8km/h) @ 1000rpm
5.9kts (10.9km/h)@ 1500rpm
7.1kts (13.1km/h) @ 2000rpm
11.7kts (21.6km/h) @ 2500rpm
19.0kts (35.1km/h) @ 3000rpm
23.7kts (43.8km/h) @ 3500rpm
27.6kts (51.0km/h) @ 4000rpm
32.0kts (59.2km/h) @ 4500rpm
35.3kts (65.3km/h) @ 5000rpm
40.0kts (75.0km/h) @ 5500rpm
40.8kts (75.5km/h) @ 5600rpm (WOT)

[Flex]

Just reading performance bulletin on noosacat website. Now I know they are totally different boats mono v cat. But the 115 had better economy of roughly 1.25km/l and the 150 was much faster cruise but coukd only manage a smidge better than 1km/l.

So even though your cruise is up your economy may actually suffer a bit.


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[WildFishExpeditions]

I dont know if you will ever really get the same economy from a 150 as a 115. the 150 is +800cc bigger, so its unlikely you will go through the same amount of fuel realistically. maybe the 2003 115 is a different size block to the new 115. I have a 150 and i can get 2km/L at cruise. however this is a 3L block. my fishing buddy has a 140hp which is a 2L block. every time he will use less fuel than me, but its also be expected since my displacement is 50% bigger than his.

[FisHard]

If you're doing a 100nm return trip, loaded up like that, and only using 100l, stop worrying about your economy, that's awesome!

[Gotty80]

That last trip was 60nm for that 100ltrs.



Followed a mate out on that trip in the dark at around 16-18knots.
His boat was planning but mine not so much until around the 20 knot mark.

Spoke to cruise craft, and they set them up with yamahas on the second hole down.
My motor is on the 3rd hole down so im gonna try moving it down one.

Im hoping this may help it onto the plane at lower revs maybe?

[Duckfish]

Hi Inveratta. Would you know what type and pitch of prop they were using?
Duck

[Skusto]

That last trip was 60nm for that 100ltrs.



Followed a mate out on that trip in the dark at around 16-18knots.
His boat was planning but mine not so much until around the 20 knot mark.

Spoke to cruise craft, and they set them up with yamahas on the second hole down.
My motor is on the 3rd hole down so im gonna try moving it down one.

Im hoping this may help it onto the plane at lower revs maybe?

If the motor is not currently cavitating or blowing out in rough seas then I would not recommend dropping the motor as it would only increase drag.


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[scottar]

You need to look at trim tabs or a permatrim to generate stern lift or try loading adjustments so the boat is planing properly. If you are pushing water trying to go slow the economy will be horrible

[inveratta]

hi inveratta. Would you know what type and pitch of prop they were using?
Duck

17 inch enertia proP SS

[Gotty80]

cheers guys,

yeh i have no issues with blowing out.

currently running a permatrim.

hmmmm

[scottar]

Relating your situation to the situation with my own rig - you have added 40 odd kilos to the transom by Yamaha's website numbers and basically upset the balance of the boat a bit - thus requiring a faster speed to get the hull working properly again. My Victory was the exactly the same in comparison to a previous one I had driven with less transom weight. I was using a litre of fuel to travel 600 metres prior to fitment of both trim tabs and permatrim when it was rough due to having the bow in the air and the hull not working efficiently when trying to travel slow. After fitting the planing aids, at the same revs depending on load I am now achieving anywhere from 1.1 to 1.4 km/L - running with the tabs (12x9) fully down or there about and varying degrees of negative trim depending on just how rough it is. This has reduced my "clean" planing speed from about 20 knots to about 15. Just out of interest, did you have your leg tucked in or had you trimmed out?

You may also want to look at props - a change to a large bladed propeller design made a further improvement with my rig but by a long margin the biggest change was bought about by the tabs and foil.