Rotary vs Rack & Pinion Steering - Will It Fit?

[KingNugz]

Hello Ya'll... So... I've finished my 1973 Rinkerbuilt TriHull Rehab.
Actually, I've had it finished for 5 months, and for the last 5 months I've been getting screwed over by mechanics here in Indiana. I've got a 1973 Evenrude 50 hp and it's been completely rebuilt, both upper and lower units. And yet... it kept having the horn on the throttle go off EVERY time I fired it up in the water. (Within 45 seconds of running).
So... apparently there was a piece of the impeller lodged way up in the upper shaft... somehow.

So... now I've just got a brand new 50/55 MinnKota trolling for the center hull mount. Only need 2 more upgrades to be completed. 1) a convertible bihimi top...(custom make to cover all 4 seats) & 2) a new steering system.

So... My question. I have a 13' rack and pinion (its screwed) and want to upgrade to a rotary teleflex system. However I only have limited space under the (dash)... as many of you will understand... has anybody put in a rotary system...? And I heard it has to match up to the same ratio as my r&p... ie...3.0, 4.2, turn ratio, Anyone know anything else about that?

I'm trting to post some pics now. Thanks to ALL Our 3Hull Bosses

 

[canuckmark]

I replaced the steering system on my 15' Grew two years ago with the NFB 4.2 rotary single cable system. Are you only looking to replace just the helm? I actually just needed to do the cable, but in the end it wasn't much more to just get a whole new kit. Then the helm and gears are new and lubed and the cable is all clean and straight.

Also most have the no feedback design - a bit different to get used to but in the end very nice.

BTW it doesn't matter if you get a 3 or 4.2 turn system, that's a preference thing. I had the 3 and got the 4.2 and like the change. A little less effort is needed turning the wheel with the 4.2.

 

[GA_Boater]

KingNugz

Moved the post from the Tri-Hull thread here to Steering and Controls.

Will a rotary replace a rack & pinion? Sure if you have enough room for the box, The box is not much larger than the dash bezel on the UFlex pictured below.

 

[KingNugz]

Canuckmark... thanks... I'm doing the whole system change... but how will i KNOW if the rotary system will fit... and if i hav a 13' r&p now... do I go with the same size or go up to 14'?

 

[canuckmark]

Cool on the whole system change, it'll be night and day.

Mine went from a rotary to a rotary. There still is a need for clearance on the starboard side as the cable goes in one side at the top and the "excess" goes around and out the bottom to a plastic tube. As for if it will fit your situation, where are you concerned about clearance, the side? Depth or the helm?

If it helps I can take a pic from behind the dash when I get home.

Is the 13' question regarding cable length? The cable length is pretty critical to get right. Too short is obvious, too long and it will bind up. Mine was on the long side but there was enough room at the back for the cable to loop down then back up. The spec for cable bends is no less than a 8" radius.

You may want to go to the Seastar website and look under Support>Installation Manuals. There's good stuff there specific to whichever kit you choose so you know what you're getting into. There was also something there I think on how to measure exactly for which cable length you need.

 

[KingNugz]

Yeah... I'm a little worried about fitting behind the dash... it's kind of spacey... for a 1973... I've done ALOT of work and rebuilt it from the ground up... so, needless to say I don't want to mess nothing up...

The space is semi triangular with a flat top... that is about 4 inches wide (at the top) and roughly 9 1/2 inches wide at the base. However it's only about 10 inches long. And the CURRENT rack and pinion system is a TOTAL of 13 foot... I've read several website posts that give some type of explanation like...measure the hull to center steering wheel, down the side, & then to the outboard center on transom... then add something and round up... then the other was measure the black tube... add 18 inches... round up to nearest foot then add 6 inches... it's VERY confusing.

But the problem is either way I do it... it comes up either 13' or 13 1/2'... and i do NOT want to go to short as I KNOW that drama... it happened with on of the used one that came with the boat.

Have you had an opportunity to view the album link I posted... maybe that could help you see exactly what I'm seeing. Thanks

 

[canuckmark]

I couldn't access that link, it might be because I am not on Facebook anymore.

Yesterday was nuts for me so I couldn't get to the boat to take pics. I will try to do it tonight.

Clearance needed on the left is minimal, but the right side might be problematic. The cable at the top and the "excess" tube at the bottom are pretty rigid - I had a bit of an issue with the cable bumping into a horizontal brace at the gunwale. The excess length kinda looped down at the back before it made the turn into the motor.

You've probably already read this before, but this is how I measured mine. The old cable didn't give me a P/N, so as per Teleflex instructions I measured the old cable jacket then added 18", then rounded up. The round-up was quite a bit - without it I was only a couple inches up from a round number, but it was better to find a way to deal with the excess length than to be too short!

One side note too - when you install the bar to the engine tube make sure it is very clean and smooth inside, then use a good marine grade lube in the tube and at the ends. I got a tube of Evinrude Triple Guard Grease (other companies have their versions) and it really is superior to generic grease - it repels water along with lubing. It is incredible stuff.

 

[KingNugz]

Canuckmark... thanks... so... if the whole rack and pinion system is 13'... and when I've measured the cable and added 18" and rounded up... it seems to come up to 13'... should i get 13'? Because the instructions on alot of sites say do the whole measuring as if your installing a new one for the first time... it seems the same... I've got a 15 1/2' boat... 16' as listed... is 13' or 14' more logical? I'm leaning towards 14'... as long as the transom matches up correctly... if theres any extra do i just pull extra thru or leave it and just try to compensate the slack elsewhere.?

 

[GA_Boater]

From the iboats.com How-To's - Measuring cables on the bottom of the page

And a video showing the size of a rotary helm

 

[canuckmark]

Try measuring using the from-scratch method in that first link GA posted. You can really visualize from the graphic there where the cable length is measured to/from. Then compare that to the 13' length you have come up with. If it is the same I'd go for that.

I was in your situation too - it is a hard pin to pull if you are unsure. But those two methods are the best ways to measure. As for any extra, remember it doesn't flex too well and the only place any slack can go is along the front-to-back run, usually at the back. But too many s shaped flexes will make the steering stiff and wear the cable quicker. So the closer you can measure the better.

Don't know if this helps you regarding helm size, but this is how mine fit. The front of the dash (so you can picture how close the gunwale is:

Now the back, from underneath looking up and back. See how the cable-in and cable-out went into the gunwale area. It just fit:

Also that is the 4.2 helm so it has the extra round bump on the port side.