View Full Version : Cable rack to Hydraulic steering conversion

05-08-2012, 09:43 PM
So I was looking into a hydraulic steering system for my 08 Supra Launch to reduce the slop in the rack style steering as well to improve the 2 hand turning method when the sacks have 2200 lbs of ballast in the boat. Yes I said Supra, but Supra/Moomba, Same manufacture so same improvement. I looked all over the Internet to try to find some sort of information about this conversion and after checking every wakeboard boat manufacture forums I came up with nothing. So I started my research and found a solution.

Items needed.
-Seastar sport helm pump. Before you go and buy all of this gear make sure you have the Seastar SPORT tilt helm. The seastar SPORT tilt helm is what comes on moomba/supra from the factory but with a cable rack behind it, however there may be some oddballs out there. As for the helm pump, You need the pump with the flat!!! adapter shaft. (see pictures) The taper/Splined ones do not come with the proper mounting holes and shaft and will not work with your sport tilt helm. Finding the pump alone without the tilt helm is a bit of a challenge but I managed to find one on Ebay for 270 brand new, shipped to my door.
-Hydraulic ram. I got a Seastar BA135x7-BJ. It has a 7" stroke which is the same as the cable steering on the boat. I found it on ebay for 80 bucks recently rebuilt and shipped.
-Seastar hydraulic lines. You will need 2 of them. My boat is 21 ft long and 20 foot ones worked perfect with extra to spare. Better be long than short, you can always coil them up with no worries unlike a cable setup.
-The last item you need is a bracket to mount the ram. I made one out of 1/4" steel cut and welded into shape. I would have preferred aluminum or stainless but the steel was at my disposal. It is essentially 2 6"x6" pieces of steel with the holes drilled in them welded at the correct angle for the ram.
-Some stainless hardware found at home depot.
Once you have all of the parts needed, you can start the process.

Remove the old steering cable making sure to tie a rope to the end so you have something to feed the hydraulic lines through. Remove the steering cable mounting plate bolted to the bottom of you hull by the same bolts that hold your strut on. Take the 2 pieces of steel and drill holes in them that match the ram and the mounting bolts on the bottom of the hull. Due to the fact that the ram is longer than the cable setup, I had to switch the 2 aft (longer) bolts with the forward (short) to accommodate the longer ram. MY strut has 6 bolts total. Note the picture attached on which bolts I used. After mocking up the ram and the pieces of steel, tack them together and make sure you have full travel on your steering. After verifying everything is in the correct place and angle weld it up solid and preserve the crap out of it. I powder coated mine to try to make it last. After getting the ram mounted, the hard part is over.

The helm is fairly straight forward and requires little fab work. You have to start by removing the 20 degree shim to allow the much bigger helm pump to clear behind the wheel. You can see in the attached pictures the helm mounted without the shim. Once removed and bolted back up, trim the bolts to allow the helm pump to mount up. Bolt it up with the same bolts used to hold the cable rack in place and put your steering wheel back together.

Plum the lines to the helm pump and the cylinder. BEFORE YOU TAKE THE BOAT FOR A TEST SPIN, ENSURE THE RUDDER TURNS THE CORRECT DIRECTION. If it doesn't, it is as simple as switching the lines on the helm pump. Once everything is plumbed up and all of the lines are zip tied securely, Bleed the system per the seastar instructions. If you want to spend 20 bucks a quart (you need 2) on seastar hydraulic fluid, by all means do so... After working on a farm for years I have realized that dexron/mercon 3 does the same job at a 1/4 the price. It works great on my setup.

Once everything is bled and ready to go, Enjoy a beer and take the boat for a spin and be amazed at how much improvement this is. I filled the sacs up and was able to turn the boat on a dime with one hand with barley any force. Absolutely no play in the steering as well when planed out.

The whole setup cost me around 400 bucks minus the beer and about 6 hours to fab up. THE best 400 bucks I have spent on this boat.

05-08-2012, 09:50 PM
Here are some more pictures of the install.14226142271422414225