BIG Outboard Engine by 7 Marine

brian eiland · 03-31-2011, 02:27 PM

This reports on the new Seven Marine 557hp Outboard.
http://www.boats.com/blog/2011/02/se...ami-boat-show/

This picture shows their "Propriety transfer case" which many are assuming to be a belt or chain. If its a belt, that is one heck of a belt.
http://www.boats.com/blog/wp-content...rick-davis.jpg
Does anyone have any details??

Eric Davis was asked how the engine’s power made the 90-degree change in direction to mate to a drive shaft, and he just shrugged and smiled. “I’ll have to explain that to you later,” he said. Apparently the Seven team is not ready to reveal all of its secrets.

We do know that shifting is accomplished above the gearcase. The gearcase has a four-inch-diameter tube – a standard size – but has twin pinion gears to transfer power from the vertical drive shaft to the horizontal prop shaft, while keeping the size of the case small and hydrodynamic. An integral power steering system was developed with the input of Latham Marine, and the motor will be rigged with custom Hering propellers.

K1W1 · 03-31-2011, 05:47 PM

Hi,

Given by what looks like the ass end of the engine and it's associated casings we can assume it has a big rubber belt driving a horizontal shaft to a bevel gear or two.

The bottom end being fairly standard.

The top end drive will be not unlike a differential but it wont need spider gears ( or by the time it does that is the least of your worries)

brian eiland · 03-31-2011, 07:37 PM

I'm betting it's a 'silent chain' belt like they used in an early Olds Tornado front wheel drive car to mate the engine-transmission

YachtForums · 03-31-2011, 07:54 PM

ZF is manufacturing the transmission and the lower unit is a twin-pin proprietary design. The most amazing aspect of this new outboard is the audacity of the manufacturer to ask $75k per motor. Good luck!

SHAZAM · 03-31-2011, 09:18 PM

Quote:

Originally Posted by YachtForums

The most amazing aspect of this new outboard is the audacity of the manufacturer to ask $75k per motor. Good luck!

I can't comprehend this. I've always believed that big boats need to be inboards rather than having to have three or four monster outboards. Is there anyone here that would rather have two of these on their boat rather than a pair of modern four cycle common rail diesels?

Capt J · 03-31-2011, 10:12 PM

The motor is based off of the chevy I think it was 8.1. I'm willing to bet it has a large Cog belt, like the superchargers they use on raceboats do. I too cannot comprehend the use of outboards of this size. However, at the miami show Intrepid had a boat there with 3 or 4 of them on it, and they seem to not know how to design a boat with inboards because even on a 46' they stuff 4 engines on it.