Power Thruster

[Bamby]

I ran into this product "Power Thruster" and it sure seems simple enough, but does anyone suppose that it would actually work with any resemblance of their claims. I sure feel I could utilize it if it actually worked...

Improve your sailboat outboards thrust and save on fuel too!

That is not an empty claim. The PowerThruster will increase your outboards acceleration by as much as 22% while saving at least 30% on fuel! Sailors report that the PowerThruster greatly improves their outboards power and handling, especially important when maneuvering in tight spaces.

How confident are we about the performance of the PowerThruster? So confident the product comes with a 100% satisfaction guarantee.

Designed by Bert Heidenreich, a fellow sailor, the PowerThruster leverages the technology used on tug boats to maximize propulsion. It is simple to install and comes with clear installation instructions. Holes are predrilled and allow for any necessary adjustments after installation.

Made of stainless steel and manufactured by Garhauer Marine, you can be assured of top quality and long life. That assurance is supported with a 10 year warranty. The PowerThruster will likely last longer than your engine. But it is easy to transfer to a new engine when the time comes.

Let the PowerThruster help you save fuel and get to the best spot in the moorage first!

http://shop.sailboatowners.com/prod....at%20Outboards

Any Thoughts....

[PAR]

Well, regurgitating the advertising isn't especially helpful, how about some base line and comparative testing preferably by independent sources.

The "hood" shown will improve thrust vectoring and improve pressure bleed off at the top of the prop swing, but a full shroud would work better. The full inch tip clearance suggest it's not nearly as efficient as the "sailor claims" might enlist. a hooded prop need very tight tip clearance for real efficiency gains. This isn't speculation on my part, but simply well proven and tested fact, on similar devices with other hooding attempts.

[michael pierzga]

I have no idea.

A tunnel will always improve thrust. How does it behave when the boat hobby horses in sea way ?

Normally with an outboard powered sailboat a big weakness is reverse thrust when docking....will the tunnel help reverse thrust ?

Since its cheap, what the heck...buy one and give it a try. Be alert..its stainless steel so pay attention to corrosion issues when you fit it.

Of coarse since the unit is so simple you might just pickup some eglass fabric, resin and a plastic bucket for a mold then make your own.

[Bamby]

So it appears it may be a somewhat potentially useful gimmick . Your responses are somewhat like I actually expected. But as michael stated it is relatively "cheap" so I may still get a set and see for myself . After all it wouldn't be the first gimmick I've ever been hoodwinked with .

[michael pierzga]

For what its worth all the local search and rescue ribs have shielded...tunnel...props on there outboards. I expect for safety not performance.

[Submarine Tom]

Originally Posted by michael pierzga

For what its worth all the local search and rescue ribs have shielded...tunnel...props on there outboards. I expect for safety not performance.

None of the SAR RIB's I've driven (about 14 over 10 years) have shields, tunnels or shrouds around their props.

-Tom

[powerabout]

Used on the 20-25hp ribs in the surf in OZ as they are near people.
Kills the performance

[powerabout]

If you want more reverse thrust you just have to bleed exhaust out of the engine before the prop or get a prop like I have seen on a 15 Nissan where the hub is larger then the gearcase bullet so in reverse the gas comes out the gearcase end of the hub,clever.
Clearly a bit more drag in forward but fine for a displacement boat

[PAR]

Again, the data has long been in on ducted props and other enclosures and tip clearance issue is one of the major concerns. Too much and you're not doing anything more then adding some drag.

[philSweet]

Don't you think that OB mfgs would offer a foot built that way for that application if it was worth 20-30% gains? The only thing that arrangement could do is to straighten out the inflow condition to the prop when the boat is porpoising, but it isn't big enough and would need to be in front of the prop. As a duct, is seems to be flat metal and won't contribute any pressure thrust itself. all it can do is change the pressure on the prop blades. That isn't going to help efficiency on a slow sailboat. A diffuser duct might let the prop operate closer to its design point, but that adds a fair bit of drag and expense. Theoretically, a prop in a duct can be set up to have the same performance as a nonducted prop of the same outside diameter as the duct. Several serious attemps to circumvent the prop diameter limit of an outboard by using ducts to simulate a larger prop have been undertaken. None have shown any remarkable improvements on the back of a sailboat. The best effort I've seen was described on the blog of the rebuild of "CC Redeemed", but I can't find it anymore.