Thinking of buying an 8.5, now the engine?

Bigmuz7 · 12 February 2006, 22:30

Hi guys, new to this forum, so Hello all!

Buying an 8.5 this year but stuck on engine options, firstly dual/single?. Have had previously a 5.8 with a Mar/merc 135 2 stroke, and then a 6.5 with 150 optimax. Both excellent boats & engines, wondered about twins for my next 8.5 or a big single, ... 275 Verado is nice but thirsty at full welly, also expensive. Anyone tried E-tecs, help would be appreciated. Should say, just day cruising, Have spare engine etc. Dont carry heavy loads.

Turbodiesel · 13 February 2006, 15:28

Well twins do look and sound so much better!!, But maybe you only need twins for off shore work were you have a spare engine incase anything goes wrong. Also you will save alot of fuel with a single, you will save servicing costs and you can go quicker as there is less drag in the water.
But if i had the money i would have twins anyday!!

As far as engine choice goes the Verado is a pretty awsome bit of kit, i would go with what you know already Mercury or Mariner. Also before buying engines look at what back up you will get after sale and were is your nearest dealer etc etc.

Bigmuz7 · 13 February 2006, 19:05

Thanks Turbodiesel, for your time to reply. If a 275 would push that boat adequately, how much more gas would I burn with say two 150 opties (as a rough guide) I Wouldn't like you to quote specifics, if the 4 x 250 tests with RIB international are any to go by!! LOL . On that subject though I noticed no one mentioned, despite pages & pages of posts that, if one of the boats were rigged with the engine, particularly the Verado too low,, jesus, that makes a world of difference to its performance and fuel economy. My opti was lifted 2 holes on the transom, & I gained 1000rpm with the same prop!, after which the motor was singing, not labouring, anyway, your advice would be appreciated. I do go off shore from time to time, just cant get head around all the extra rigging etc.

codprawn · 13 February 2006, 19:45

Being a Scotsman I would have thought there was only one thing you would look at - price!!! Seriously though there seems to be so little really to choose between the engines the best deal on the day is what prob counts.

Suzuki seem to have some great deals around at the moment - my leanings would be to the Etec 250 as it's nice and light but the Suzuki isn't bad for a 4 stroke.

Good point about the rigging - ordered a transom jack on mine.

Turbodiesel · 13 February 2006, 21:31

Its very hard to say what the fuel consumption will be, There is a very ruff way of working it out but its for a single engine.

You take a third of the horse power and that will give you a figure for a normal 2 stroke carb engine at wide open throttle for litres per hour.

eg, a 150hp will burn approx 50 litres an hour at WOT(wide open throttle)

For a opti and a four stroke take a third off that figure again.

So that would be about 33.4 litres an hour at WOT.
But it makes a differance as to what boat its on, how much weight if its propped correctly etc.
So its only a ruff calculation, but thats what we go by at work for calculating fuel consumption. Hope that helps.

Richard B · 14 February 2006, 00:14

Hello Bigmuz7,
It would be good to find out exactly what you want from your boat before recommending an engine.

If you are interested in coastal day cruising in shelteres waters, then there's probably no need for twin engines, unless you are a petrolhead and want performance... in which case you'll probably want two engines just to get enough HP on the transom.
Also what hull is it? A heavy deep V boat will need more power than a light shallow V boat to gain the same performance.

In summary, a single engine for simplicity and fuel efficiency, twin engines for raw power! Which one is your thing?

Ezgoing · 14 February 2006, 00:18

bigmuz,

Remember two engines means twicw as many problems and extra weight.

As regards going offshore will you be in company of other boats? DO you really need the second engine.

As regards engine choice hae you considered Yamaha?

rgds

Bigmuz7 · 14 February 2006, 08:51

Thanks for that guys. Not a lot in it then Turbo, For a 275 Verado, that comes out at 60lph, which is not much less than two 150 optis @ 33.4 ea. Well I do go out in a variety of sea states, do like a bit of speed now and again, but dont like to visit the pumps too often , not asking for much am i? lol The hull will be a deep V RIB, possibly Northcraft again. The thing I like about the Verado is the electronic throttle & shift, less clutter to rig. However, its the biggest output from that block that Mercury produce. The 200,225,250 and 275 all have the same cc, so I assume the ECU has been remapped, with a thirstier set up to get the power, so i'm wondering, if it will need a refinery to feed it, I know they are well thirsty at wot.

Cookee · 14 February 2006, 09:18

Miami boat show starts this week and there may be an announcment about a 300 - possibly!

Turbodiesel · 14 February 2006, 10:18

Well the DTS (digital throttle shift) is pretty amazing, its way ahead of everything else at the min. I think if you go out on a boat with a Verado you will want to buy one!!. And yes the 275hp has differnent mapping and a few other parts i think.

Roy Smith · 14 February 2006, 20:22

Dont buy a 275 Verardo and think you will get 60 ltr an hour. If its a heavy boat and if you like to push it, your in for some shocks.

Bigmuz7 · 14 February 2006, 20:40

Thanks Roy , I saw the 250 test in RI which suggested the 250 gets 72lph when maxed out, I mentioned earlier also that the 275 will be worse, we were generalising about engines on general rev ranges with reference to the 60lph figure, so I know thats not the norm. The verado has worried me about its consumption on wot, but I'd appreciate if you could be more specific, and let me know what exactly you've experienced with what set up ,, Cheers

jwalker · 14 February 2006, 22:31

At wot, most petrol engines are going to be using about the same fuel for the same power. Engine efficiencies will not be greatly different across the engine types and there is a limited amount of energy available from the fuel. At part throttle it may well be different because some engines can waist a quantitly of fuel.

Actionboat.dk · 15 February 2006, 14:15

Bigmuz
go for the twin 275. why aime low??

twin 275 max with 14 people in 60 kn

then you don't have to give full trottle all the time..
BR Jan

Fjordrafting · 20 February 2006, 21:06

Why aim low? Go for the all new Merc 300 XS shown at the Miami. Only 235 kg each!

Roy Smith · 20 February 2006, 21:35

If you can wait the new 3.5 ltr V8 four stroke Yamaha should be here late season

Pete7 · 21 February 2006, 08:31

Quote:

Originally Posted by Roy Smith

If you can wait the new 3.5 ltr V8 four stroke Yamaha should be here late season

what ever happened to a BWM 18 and a pair of mariner 40s

Bigmuz7 · 21 February 2006, 09:03

Well its all about progress (isn't it?) hehe, right lets rip off those tubes and stick a gas turbine on either side 20000 lbs of thrust each ... well thats the chine waliking sorted ... lol

Roy Smith · 21 February 2006, 21:15

Quote:

Originally Posted by Bigmuz7

Well its all about progress (isn't it?) hehe, right lets rip off those tubes and stick a gas turbine on either side 20000 lbs of thrust each ... well thats the chine waliking sorted ... lol

Your dead right just how quick can you go in a force 5/6

Bigmuz7 · 22 February 2006, 22:12

Man am I stuck now , two 150 verados or a 275 come on Roy, decide!