Merry Fisher 805

Racingfrank7 said:
I am suprised tho that u could bore a 3lt out to 3.5lt with out making each bore a lot weeker or very thin between cyls.
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Not sure what you're referring to here. The Nanni is a 4 cyl 3.0 (same as it was in the Landcruiser), the Volvo is a 6 cyl 3.6. Not sure where the idea of over boring came from ?

I said cheaper to maintain, not necessarily less maintenance. Oil filters and engine fuel filter are available from auto factors for peanuts. Primary filter is very cheap. The cambelt is same as the Landcruiser and costs peanuts again, takes a couple of hours to fit. Doesn't the Volvo have a supercharger too ?

Like i said, nothing inherently wrong with the Volvo engine. If i was looking at two identical boats, i'd have the one with the Nanni over one with a Volvo. If the Volvo engined boat was otherwise better equipped or in better condition, that might be a different matter (as you suggest).
 
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rustybarge said:
It's hard to get an exact fuel consumption figure.Mbm were using erroneous figures for years.(manufactures perfect case scenarios).

They got a nasty shock when they did the ultimate engine test in Feb 2012.
170-200hp uses 4gal/hr, that was about right.
350 hp uses 8.5 @ 2500, not 7 gal.
Biggest underestimate is the 300hp which uses 7.gal/ hr , not 5gal.
Makes a massive difference to mpg figures!
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Those figures bare no relationship to the boats and engines under discussion.

The 200HP Nanni in the 805 uses 25-30 litres an hour.

The 285HP KAMD300 in the 925 uses 30 litre an hour.

Those are real World figures.
 
PaulGooch said:
Not sure what you're referring to here. The Nanni is a 4 cyl 3.0 (same as it was in the Landcruiser), the Volvo is a 6 cyl 3.6. Not sure where the idea of over boring came from ?

I said cheaper to maintain, not necessarily less maintenance. Oil filters and engine fuel filter are available from auto factors for peanuts. Primary filter is very cheap. The cambelt is same as the Landcruiser and costs peanuts again, takes a couple of hours to fit. Doesn't the Volvo have a supercharger too ?

Like i said, nothing inherently wrong with the Volvo engine. If i was looking at two identical boats, i'd have the one with the Nanni over one with a Volvo. If the Volvo engined boat was otherwise better equipped or in better condition, that might be a different matter (as you suggest).
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The Volvo is a 4.1 hence the name ( tamd41 ) and no super charger,
Turbo Aftercooled Marine Diesel 4.1 Thats why it doesnt have a K in the engine code.
 
I've learnt something else then !
It was a marine engineer that told me the above. Shows what he knew !
Glad he doesn't work on my baby !!!
 
I sold my 725 which had an outboard on it. I am keen on petrol outboards and I understand it can't be an option for larger ones, It was great on fuel, and I even had shower in my 725 which I designed it myself! so we could stay on it on weekends.

They are great and versatile boats. In the same class (assuming you go for 805 and above) you have not got many other options - sealines are good for family cruise, but not fishing and dirty jobs. Quicksilver is small and far from merry fisher...

So go for it. You will love the package. I think 805 has bow thruster as well.
 
PaulGooch said:
I said cheaper to maintain, not necessarily less maintenance. Oil filters and engine fuel filter are available from auto factors for peanuts. Primary filter is very cheap. The cambelt is same as the Landcruiser and costs peanuts again, takes a couple of hours to fit.
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Thanks for posting that info Paul, and also for

The 200HP Nanni in the 805 uses 25-30 litres an hour.

The 285HP KAMD300 in the 925 uses 30 litre an hour.
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That is real world info much appreciated by a novice like myself :)

Alan
 
vandy said:
I sold my 725 which had an outboard on it. I am keen on petrol outboards and I understand it can't be an option for larger ones, It was great on fuel, and I even had shower in my 725 which I designed it myself! so we could stay on it on weekends.

They are great and versatile boats. In the same class (assuming you go for 805 and above) you have not got many other options - sealines are good for family cruise, but not fishing and dirty jobs. Quicksilver is small and far from merry fisher...

So go for it. You will love the package. I think 805 has bow thruster as well.
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Hi van,

What sort of fuel consumption did you get with a OB?
is the 725 too big to be a trailer boat?

The latest Suzuki lean burn outboards seem to equal the fuel consumption of an equivalent diesel. The purchase cost is about half, so maybe it's starting to make sense!
 
rustybarge said:
Hi van,

What sort of fuel consumption did you get with a OB?
is the 725 too big to be a trailer boat?

The latest Suzuki lean burn outboards seem to equal the fuel consumption of an equivalent diesel. The purchase cost is about half, so maybe it's starting to make sense!
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I have a Suzuki 115 which I roughly estimate consumes around 23 litres per hour at 4,700 RPM or just under and that gives a SOG of 21knots.

This is a lot better than the consumption I first expected when we purchased the boat. If I push it over the 5,000 RPM to say 26 knots then the consumption does seem to jump a lot higher. Having previously owned a sailing boat we are more than content at 21 knots.
 
Matt341 said:
I have a Suzuki 115 which I roughly estimate consumes around 23 litres per hour at 4,700 RPM or just under and that gives a SOG of 21knots.

This is a lot better than the consumption I first expected when we purchased the boat. If I push it over the 5,000 RPM to say 26 knots then the consumption does seem to jump a lot higher. Having previously owned a sailing boat we are more than content at 21 knots.
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Hi matt,

Just guessing that your boat is smaller than a MF 725?
 
I had a 150hp Yamaha 4 Stroke - cruising at 4500rpm, according to fuel flow meter I had, I could get 0.9ltr/nm. That was just about 28 knots.

Mine came on a double axle trailer - however I had the trailer stored in the marina - I have seen number of them kept on dry stand, or ashore on their trailers.

When I bought it, the guy told me he had to modify the trailer to avoid damaging the hull as heu used to launch/recover. I recovered it just on the day I sold the boat and realized how easy it would have been if I had kept it on the trailer so I could explore more places with it....all you need is a well greased trailer!

These days petorl is available in all marinas in the southcoast and in quite a alot of places - I don't know about diesel engines, and there are so many instructions and manuals on how to fix/maintain outboard engines so I am keen on using the outboard. Also, you avoid getting worried about seacocks, shaft leaks, etc.

I tried my friend's Quicksilver which had an inboard on it, I struggled with it as outboard has much better throttle response and you do need it when berthing etc..
 
Matt341 said:
Yes it is smaller - 6.80m.
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I was comparing the fuel consumption between the Antares 6.8 which you've got @ 3.5 mpg approx, to he Finnmaster 6.1 which does 6.5 mpg.

With he new Suzuki lean burn which are 2o% more efficient, I was reckoning £1/nm or less would be possible.
 
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I totally agree with what you're saying about outboards, and they don't mind idling all day long: try that with a diesel.

0.9 ltrs /nm is fantastic, I always thought that 150hp OB is a better choice than 115, which has nearly identical consumption but twice the torque.
 
rustybarge said:
I always thought that 150hp OB is a better choice than 115, which has nearly identical consumption but twice the torque.
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With these boats, getting them on plane is such an important factor in your fuel consumption - 115 struggles especially with a big tank of fuel and 4 man on the boat. Don't worry too much on which make of outboard you get, these days they are all reliable, and quite close in terms of fuel consumption - just workout if you are close to a particular dealer and then it will make the life easier.

I am minded to say avoid E-Tec/Optimax - have seen people either love them, or being so confused (both owner/mechanics) as overcomplicated.

Post 2005 Suzuki, Yamaha, Honda, and Mariner/Mercury EFIs are all fantastic engines - have tried different HPs of all of them on previous ribs/boats, and never had an issue.
 
Post 2005 Suzuki, Yamaha, Honda, and Mariner/Mercury EFIs are all fantastic engines - have tried different HPs of all of them on previous ribs/boats, and never had an issue.[/QUOTE]


So do you think the latest 20% more fuel efficient, or is it just advertising hype?

I do know that cars that are advertised to do 80mpg definitely don't do it, more like 50-60 mpg. When I think back I had a mini 850, 1960 that did 5ompg, that's not much progress in half a century!

Maybe the the outboard spec. Figures Are the same.
 
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