90 hp mercury saltwater series fuel usage ?

[thomo730]

Hi all,
Looking at savage osprey 5.5m with 90 merc 2 stroke all 2003 ,wanting
to know fuel usage at idle, cruize and wot. From memory its only
2 litres per hour heavier than most 4 strokes but cant find thread again.
Any help would be much appreciated thanks,
Thomo

[Crocodile]

Hello Thomo,
have a look at the Yamaha performance bulletins.
Mercury no longer show the bulletins for 2 stroke motors, I think that there is a four stroke conspiracy afoot.
Contrary to popular opinon there is very little difference between makes.
The ######## reports are good too.
Remember that a US gallon is 3.8 litres.
An imperial gallon(as used in Australia) is 4.55 litres.
These results have been achieved under ideal conditions, so real-world figures may not be so good.
http://www.yamahaoutboards.com/sites/default/files/bulletins/bulletin_2stroke_hpmidport_bss_sct-180bayscout-90txr.pdf
http://www.yamahaoutboards.com/owner-resources/performance-bulletins/archive
http://www.########.com/boats/boat_video.aspx?ID=1207#Test-Result
http://www.########.com/boats/boat_video.aspx?ID=540#Test-Result

[Crocodile]

Hello Thomo,

######### means boat test(oneword), must be an ausfish thing.

[Noelm]

A 2 stroke carby model motor will use a lot more than 2 litres per hour more than a 4 stroke, no two ways about that, I would reckon compared to a 4 stroke, a carby model will use around 40% more fuel, and that is for any brand. The trade off is, weight, simplicity, and price, you need to make the decision

[WalrusLike]

One bloke said to me it's like pre paying for your fuel at today's prices. So the extra money pays back over time.

But it's a lot of money up front and dearer in servicing. So depending on your usage you can come out square, ahead, or behind even.

[oldie]

i owned a 90 Merc 03 model, on a 16ft glass boat, the Yamaha 90 is 998cc where the Merc is near 1400cc so they bat above there weight this is why i repowered with the Mercury, pushed the boat to 42mph which was 2mph less than the old v4 120hp did, one run out off tweed to 9mile trolling for 4 or so hours then home, approx 22mph speed each way, i was lucky to use 20litres of fuel, was very surprising, if you open it up obviously will use more but i felt the 22mph was the sweet cruing speed in that boat