80hp 4stroke (yam) fuel

BassBoy · 27 February 2009, 11:08

Sorry to be lazy and not search old posts! but can anyone tell me the expected litres/hour consumption of new Yam 80 4 stroke with usual combination of ragging and bimbling?
It's on a 5.8 Tornado
Thanks folks

codprawn · 27 February 2009, 14:07

A mate of mine runs exactly the same engine on a 5.4m RIB. He reckons at worst about 1L per mile but often a lot better than that. He has 2x 25L tanks and they seem to last him all day.

Went across to Ilfracombe and back from Swansea - about 26miles each way - almost flat out going over and very choppy coming back - still had a few litres left in the 2 tanks. He had a spare as well of course.

BassBoy · 27 February 2009, 16:22

Thanks Cods

So if I've got it right and you did about 25knots there and back in lets say a touch more than 2 hour round trip and you used about 45 litres, that would stack up to roughly 23ltrs/hour.
I guess I could reduce that figure alot given a mixture of bimbling, displacement and full chat, to say 12-15ltrs/hour. Bump it up a bit for slightly heavier/longer boat, so say 18ltrs/hour. Sound about right to you?

Cheers
BB

codprawn · 27 February 2009, 16:28

So much depends on the hull - he has a Ribeye which is a medium V. The deeper the V the better the boat is in the rough but the more fuel it will use.

Having said that my mate is pretty heavy on the throttle so your figures should be about right if you go easy on it.

One good thing - he is approaching about 800hrs now with no problems at all.

BassBoy · 27 February 2009, 18:06

Thanks again
As a matter of interest, do you know what pitch prop he's throwing and what WOT he gets?

Interesting comparison with my own RC with 140 Soozi that does 1.2-1.4 miles/ltr at 4,200-4,500 rpm (25knots) (WOT is 6,200rpm)

codprawn · 27 February 2009, 21:39

Will find out over the weekend.

outboardtech · 28 February 2009, 13:35

Bassboy the F80A and F80B Engines MAXIMUM fuel consumption is 27 litres @ 6000 rpm . you obviously not going to be running @ 6 grand all the time but this is how they work it out from factory .

K&S · 28 February 2009, 15:26

Quote:

Originally Posted by outboardtech

Bassboy the F80A and F80B Engines MAXIMUM fuel consumption is 27 litres @ 6000 rpm . you obviously not going to be running @ 6 grand all the time but this is how they work it out from factory .

Another quality post there

God loves ya

BassBoy · 28 February 2009, 17:20

Thanks guys. Very helpful.