$txt['youtube'] = 'YouTube'; $txt['youtube_invalid'] = '#Invalid YouTube Link#'; R & D on reverse, 2

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Offline bizler

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R & D on reverse, 2
« on: April 03, 2014, 10:21:23 PM »
  :)  I added a divider or septum to the outlet on my reverse cup.  I am pretty pleased with the results.  With it, I was able to back up continuously for as long as I wanted without doing a ground loop, or water loop in this case.  It seems as though splitting the stream to keep it away from the intake is the key to success.  It would probably be a good idea to add a rearview mirror though to avoid bumping into things, as was the occurance at the end of the video.  I actually bumped, ever so slightly, into the floating dock on which a floatplane was moored.  Have a look... 

<a href="http://www.youtube.com/watch?v=b1OfGhwPTOk" target="_blank">http://www.youtube.com/watch?v=b1OfGhwPTOk</a>

Offline Painlesstom

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Re: R & D on reverse, 2
« Reply #1 on: April 03, 2014, 11:24:42 PM »
Great job, Bill. I was hoping that would work for you. Definitely a huge improvement over your last video, that is a truly usable reverse system you have put together there.  \./8
Tom

  >:D    

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Offline bizler

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Re: R & D on reverse, 2
« Reply #2 on: April 04, 2014, 12:30:32 AM »
Here is the cup with the septum for those who migth wonder what it looks like.

Offline BarnieM

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Re: R & D on reverse, 2
« Reply #3 on: April 04, 2014, 09:09:54 AM »
Bill, I would love to have one. Let me know if you can help me.........Barnie

Offline Hillbilly

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Re: R & D on reverse, 2
« Reply #4 on: April 04, 2014, 09:31:52 AM »
So simple with so much improvement.  Brilliant.

 Bill, I'm also interested in your muffler.  Not so much for myself ( I'm happy with Tom's exhaust) but for others who want to improve their exhaust sound without modifying their boats.   Maybe you could post the info under a separate exhaust post.  There are already five different threads on mufflers on the site.  Seems to be a long history  of interest. 

Thank you for your input to the discussions.

Offline Hersh

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Re: R & D on reverse, 2
« Reply #5 on: April 04, 2014, 12:56:00 PM »
 Great job on the improvement.

 Hersh

Offline bizler

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Re: R & D on reverse, 2
« Reply #6 on: April 04, 2014, 01:00:24 PM »
Thanks, guys, for your comments.  Yes, Bernie, I am planning to make some of the septums for those who woul like them. They may require a bit of final fitting to the cup since none are exactly alike.  They will also require drilling, countersinking and tapping 4 #4-40 holes to mount them to the cup.  If you want me to mount it, I will need your reverse unit, less the cable and lever, and $25 for return postage.  I won't charge for the septum and screws.

Offline Odie

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Re: R & D on reverse, 2
« Reply #7 on: April 05, 2014, 12:14:23 AM »
I am curious of the dynamics. The septum divides the stream flow, displaces and manages velocity ?

Offline Painlesstom

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Re: R & D on reverse, 2
« Reply #8 on: April 05, 2014, 12:21:07 AM »
It splits the flow into a V, which reduces the amount of washout to the intake grate, and also provides two points of thrust to help keep the boat on course with less inclination to go into a spin.
Tom

  >:D    

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Offline Californiamokai

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Re: R & D on reverse, 2
« Reply #9 on: April 06, 2014, 11:47:10 PM »
Bill,

Question regarding how one would ideally route your control cable if you had one of Tom's muffler that extends across the width. Where would you need to then drill thru the back, assuming it would would work with that muffler location.

Secondly, once it is locked on with the reverse thrust, does it take away to any degree the steerage capability you normally would have.  Interesting approach ...........John

Offline Painlesstom

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Re: R & D on reverse, 2
« Reply #10 on: April 07, 2014, 12:13:10 AM »
A picture of your engine compartment, showing the cable routing, would let me answer John's question, Bill.
Tom

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Offline bizler

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Re: R & D on reverse, 2
« Reply #11 on: April 07, 2014, 12:21:19 AM »
Good questions, John. I don't have a way to determine if there is a path for the cable under one of Tom's mufflers but that is where it would need to be. There needs to be room for the cable to flex between the back of the hull and the reverse support.  I think that if it were no more tha a couple of inches below the bottom of the engine hatch cover it would work ok.

Since it lengthens the steering nozzle by 3" ( in order for the cup to swing from side to side) my reverse does take a bit more force on the stick for high speed turns.  There is really no perceptable difference than stock at lower speeds and in reverse.

The force on the stick would be even a little higher if the ball joint lever has been shortened, as I believe some owners have done.


Offline Painlesstom

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Re: R & D on reverse, 2
« Reply #12 on: April 07, 2014, 09:32:34 AM »
A picture of your engine compartment, showing the cable routing, would let me answer John's question, Bill.

 ;)
Tom

  >:D    

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Offline bizler

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Re: R & D on reverse, 2
« Reply #13 on: April 07, 2014, 03:12:58 PM »
Here are a few photos showing the routing of my reverse control cable in the engine compartment.  The cable could be relocated near the target dot and still function correctly.  I merely ran it through the cowling just under the lid on my Mokai to keep it well above the waterline.  The hole through the hull could be as small as 5/16" but a 3/8" hole would allow the stainless steel ferrel at the end to pass through.  This would eliminate have to remove the ferrel, which just screws on the cable covering.

The last two photos show how the cable has to be able to sway back and forth for full turns of the nozzle.

Tom can better assess whether this routing of the cable is compatible with his muffler.  To me, it appears that it should.

Bill

Offline Painlesstom

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Re: R & D on reverse, 2
« Reply #14 on: April 07, 2014, 03:48:21 PM »
Where the cable is now might be ok, but it would be a little too close for comfort I think. If it could be moved to where I pointed the arrows, there would be no problem at all.
Tom

  >:D    

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