Looking at bow thrusters for my Benford 38 Fantail Launch ( I'm getting older and lazier) I really like the idea of a belt drive thruster. Volvo has one but I will not buy Volvo products. Does anyone have any experience with "Yacht Thruster" ?
I want a bow thruster
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I've had belt drive motorcycles and have a belt drive bicycle. smooth, more efficient than gears and much much quieter. I know that the efficiency issue is counter intuitive but studies have shown otherwise. I have previously had a gear driven thruster that was extremely noisy and the boat had to be pulled when the gears got damaged. You can change or adjust the belt without hauling the boat.
What disadvantage do you see ?
What disadvantage do you see ?
N4712
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Our sidepowers have a rubber love joy flex coupling that is meant to give out before having a chance to wreck the gears. It can be changed in the water.
It doesn't look like changing a belt on the yacht thruster would be fun.
It doesn't look like changing a belt on the yacht thruster would be fun.
I had a close look at one at a boat show recently, didn't look too bad. Of course the safety cover would go right in the garbage as soon as it came out of the box.
Been there, done that, don't like them. It has always made more sense to me not to run power through 90 degree angles.
psneeld
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Most of us accept belts on our primary drive engines....
I think a belt on a tertiary system like a thruster would be fine. If you could get at least a couple years at say "looper" level use and wasn't a bear to change if access was reasonable, then a belt system would be OK with me.
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I had the same mind set 10+ years ago when I purchased H/D motorcycle; I didn't want a belt driven motorcycle, just didn't seem right. Well not one issue yet from belt drive.
Codger2
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Just yesterday, I changed the 4 blade prop on my SidePower SP55 in my old boat to the newer and much more advanced SidePower Q-Prop. I can't tell how much more thrust I gained ( I did gain some) but the reduction in the noise level is significant.
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The disadvantages to me would be:
1 There is a belt, which to me is a weak link. Yes I know motorcycles have them, but it is still a piece of rubber.
2 The link says there is no oil in the gear housing. The gear has to be lubricated, so I assume it has some type of sealed/greased bearing. Personally I would just rather the gears run in oil for maximum lubrication.
3 With the motor laying horizontally I don't think you can get it as far forward as one that the motor is vertical. Maybe I am wrong but having just installed one in my boat I don't think I could have got it as far forward as I did the Vetus.
4 You have to make a lot bigger hole in the tunnel for a belt drive than a direct drive. That would only become a problem in the event of a failure, but it is still something I think about.
I have only had the Vetus for about 3 months, but so far I am very pleased with it. I had heard of how noisy thrusters can be but I am very happy with how quit this unit is.
Mind you this is all just my opinion.
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Lobstah
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Minor point, but I believe Harley's belt was a rubber/Kevlar composite. At least mine was back in 92. That being said, they still have failures, however, I suspect that the applications are very very different, as no one is doing hole shots with their belt-driven thrusters
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Jim
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Ask a SAMS boat surveyor if any are out there and reliability, sounds like a rarity. BTW, 90 degree power transmission has been around for about 3000 years. Think about how scary up and down movement created by explosions is when connected to a shaft.
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It is made by Sleipner, Same company as Sidepower, who also builds the QL line for Volvo for the last ten years. So it is likely the same. You can find QL installation manuals on-line.
It is probably well built, although the plated motor housing gives me pause. Maybe not a consideration in fresh water, as you are.
As far as belts go, it appears to be a synchronous belt drive (cogged belt), a very reliable drive system, when engineered properly. Functionally, it is more like a gear drive, than a v-belt drive.
Wouldn't want to break a belt in season though as I can't see a way of replacing without pulling the boat. As you likely haul every winter, there is a good preventative maintenance window available to you. Belt service life would likely be very long, I'd guess ten plus years. Synchronous drives are not great for shock loads, so no running debris through the prop, to the point of stopping. Hopefully the motor breaker would go before the teeth on the belt strip. That said, gear drives aren't wonderful for that kind of shock load either.
You can lay the motor on its side aft and parallel to the tube, which is a considerable space savings. The drive leg hole in the tube appears to be about the same as for the drive leg in my Sidepower.
It is probably well built, although the plated motor housing gives me pause. Maybe not a consideration in fresh water, as you are.
As far as belts go, it appears to be a synchronous belt drive (cogged belt), a very reliable drive system, when engineered properly. Functionally, it is more like a gear drive, than a v-belt drive.
Wouldn't want to break a belt in season though as I can't see a way of replacing without pulling the boat. As you likely haul every winter, there is a good preventative maintenance window available to you. Belt service life would likely be very long, I'd guess ten plus years. Synchronous drives are not great for shock loads, so no running debris through the prop, to the point of stopping. Hopefully the motor breaker would go before the teeth on the belt strip. That said, gear drives aren't wonderful for that kind of shock load either.
You can lay the motor on its side aft and parallel to the tube, which is a considerable space savings. The drive leg hole in the tube appears to be about the same as for the drive leg in my Sidepower.
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