GPH of petrol Mercruiser 5Ltr?

Clyder

Clyder

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Any advice please, good or bad on the expected fuel consumption of a 5Ltr Mercruiser.

I'm considering trading up from an oil burning Merc. 1.7Tdi......which is a PROPER fuel-miser.

I'm hoping to trade off "livability" with the bigger boat over "useability" of the smaller.

Thanks.
 
Rule of thumb is 9gph per 100hp at full throttle, cruising speed would probably be 60-70% of the full throttle figure.

So if your 5.0L is rated at 250hp full throttle burn should be about 22gph (which at say 30kts would equate to 1.36Nm/gal), and cruising speed consumption of say 14.5gph (which at 25kts gives 1.72Nm/gal). Enter your own figures and see what you get....

In my practical experience the rule is a bit heavy on its prediction for my engine in my boat but it gives you a starting point - and if you are pleased the first time you fill up as you've used less than expected then that is a bonus and won't last long /forums/images/graemlins/frown.gif
 
Thanks for that Simon. This now gives me something to work on.

----------------

Rgds

Clyde
 
It's going to depend a great deal on your hull and size. My 21' boat has a 4.3l mercruiser, with alpha leg. At 30knts cruising, I get about 1 litre per nautical mile (it's a very fuel efficient hull, double stepped). At full throttle (WOT) fuel economy is much, much worse!
 
The boat I'm looking at is a Regal 2460. How would this hull effect the GPH? Is it fuel efficient etc? My main problems come from trading up from a Bayliner 602 with the fuel sipping Mercruiser 1.7td to this V8 gas guzzler.

At present I can get about a full weekend of cruising, skiing and donutting on 2 gallons of red!!! not to mention a few fast 20 mile runs.

I realise I will take a pounding,(£) and my watersports activities will be reduced somewhat. Any advice? Would the trade up be worthwhile?
 
[ QUOTE ]
US Gallons are actually larger (1.2x) so 'real' gallons/hour will be 1.2 better than these test results.

[/ QUOTE ]

It's the other way round

US gallons are smaller than Imperial,

From
Convert

Here's How:
1. Determine the quantiy in Imperial Gallons.

2. Using your calculator, multiply by 1.2

3. Your final answer is in US Gallons.
 
With a similar sized boat and 5.0ltr V8, I used to get through between £100 and £200 of fuel per weekend. I had a fuel flow meter fitted and would cruise at about 9gph. Full throttle would be about 15gph.
 
[ QUOTE ]
It's the other way round

US gallons are smaller than Imperial,

[/ QUOTE ]
Yup, I'm an idiot /forums/images/graemlins/grin.gif
 
Thanks for the info guys.

It would seem that I dont have a leg to stand on with the figures quoted. "Her Indoors" will no doubt throw a wobbler if she sees them. /forums/images/graemlins/mad.gif

There goes my "just dropped in by chance" to the brokerage to find "This looks good doesn't it dear?" line !!!! /forums/images/graemlins/wink.gif

I'll have to get my thinking cap on now.
 
Am i reading these post correctly??

9GPH
14GPH
22GPH.

Or £100...£200 per weekend.

Boy, i am glad i choose the boat i have got, 3 litres an hour, seems about right to me. Also i use my boat 3/4 times a week. Glad it's not using anywhere near the GPH quoted.
 
ermmm, but you've got a motor sailer. Different kettle of fish entirely. You oughta see what the big twin engine diesels get through an hour (though diesel, so costs less per gallon to fill)
 
Very true BrendanS.
I Opt for economy and a slow relaxed life, but i do wish at times, i could reach my fav fishing grounds a little faster then 6.1/2 knts.
A decent fishing trip now takes two days and one night..LOL.
 
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