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oldtimer57.
I have gotten several questions about this so I thought I would replay what worked for me.I had two issues this past year. #1 was very slow fluid loss, turned out to be the two end seals on the cylinder (attached to motor). #2 was significant “wheel creep” where a 7-8 mile run would see the steering go to the left a full circle or so. And that continued to get progressively worse. Heres my pretty cheap solution to fix this…Remove the mounting bracket on one end so that you can access both end seals, use a spanner to remove them. Probably easier to break them free before removing the end bracket. Once you have that done, remove both end caps which have seals and wipers inside. Put one in your pocket. Now carefully pull out the hydraulic shaft/ piston. There are two pieces to the seal on this thing. The outer part is made of various types of plastic, depending on the year, underneath that one is an o-ring. The o ring is not a seal, it simply exerts outward pressure on that square seal you removed first. Probably best to take both pieces plus the end cap (gland is the technical term) and visit a good hydraulic seal shop. I went to Precision Seals in Gardendale, AL. For the piston seal, tell them you want a 1.375 high-pressure hydraulic seal and show them the seal + O-ring you removed. They can match it exactly as that is a common size (regardless of what Sea Star claims – proprietary part, etc.) Then hand them the gland and they will remove the internal parts and match em up again, exactly. For me I spent less than 20 bucks for all three sets (Sea Star wants about a hundred bucks or so for just the glands, they wont sell you that piston seal, they insist you use a repair center or send it to them for repair, at a cost of about $350.Now you have the seals. The gland seals and wipers are easy to install. Use an o-ring pick and remove them. Do one end first, keeping the other end to have as something to compare to if you forget the order or direction of one of the parts. Do the other.The center (piston) seal is a bit of a pain. The seal guy suggested that I suspend both pieces (theirs came with a square-shaped rubber inner seal and the epected square plastic PTFE outer seal) and hang em in a pot of boiling water for a few minutes. Remove the black part first and carefully slide/stretch it over the piston and into the groove. Then do the same for the outer part. Heres where you run into a problem, so before removing that one from the boiling water, you want to find something you can wrap around that piston to compress the seal once you stretch it into place. I cut a 1/2″ wide strip from a soft drink can, reinforced the ends and made a hole on each end after that. I then used a decent piece of copper wire threaded through the holes. NOW you remove the plastic seal from the water and carefully stretch it on. It has NO memory so it will now be too big. Quickly wrap it with that strip from the drink can and then twist the copper with a screw driver to really compress the seal back down in size. Stuff it into your Freezer for an hour or sold to set the shape again. Now, with a little effort, you can push the piston back into the cylinder. Be CAREFUL and dont scratch the cylinder inside with the threaded end of the cylinder. I wrapped the threads on mine with a piece of shop towel and taped it so it would not fall off. A touch of oil or hydraulic fluid on the seal lip after you remove that can contraption and it ought to pop right in.Next big savings. Go to Oreilly auto parts and buy a gallon of what they call AW-32 hydraulic fluid. Will set you back about $14 bucks instead of $25 per quart for seastar fluid. Works fine. I can point you to dozens of people using this stuff, including myself for many years… They have other types but AW-32 is actually pretty close in ISO number to Sea Star. Little thicker but I cant tell the difference in mine.Bleed and you are ready to go again…
Nice write up.Thank you for sharing.Too bad greedy individuals feel the need to gouge customers.
I 2nd the AW-32 option. much cheaper and it works in steering, power pole etc.there is a very good video on youtube as well
I always considered the seastar fluid as price-gouging at its very worst. We dont need fluid with a super-high flash point. Just so long as the flash point is above 150 degrees F, it will work fine. But now that they have stopped selling parts to the general public (except for the end seals that are priced about 10x what they cost – go figure) that goes too far IMHO. Dont want to hear the liability stuff. FAR more cars on the road, yet we can buy every possible part, at reasonable prices. Boats are considered luxury items. Which seems to make price-gouging perfectly OK in the minds of some. Fortunately there are (at least currently) alternatives. Of course, if you need the cylinder, or the piston, etc, you are still at their mercy…I will always remember an exercise I did with my Astro boat salesman. I was at his shop waiting on a parts shipment he was expecting that had two pistons / sleeves for my 2.5 motor. I had recently bought an Astro with an XR6 (1992). Motor had a retail price of about $8000. We sat at the parts computer and picked out every part to build an XR6 from scratch. I called a halt when we passed $36,000 without being done. 🙂
I took my sea star off…..chunked it and installed a U FLEX cylinder assembly which is a exact match to the lines and the swivel pin. Uflex Cylinder Front Mount hydraulic steering UC128OBF-1 for a 250Pro XS paid 415.00 took about 2.0hr to install and bleed out.
I am going to use the u-flex cylinder before long, but I am going with the silver steer model which looks even stronger…
Looks exactly like the one i used,but silver. Same pivot set up as mine it appears. Believe they are one in the same. One is silver and the other black
Looking at their web page they appear to be different, not just in color. But I will check further. The part number ends in SVS I believe. Prices are certainly different…Ive talked to one person that owns one and the first thing I noticed was absolutely zero slip internally in the cylinder. Seastar always seems to have about 1/8″ of play no matter how well you bleed it. But when they decided to not sell parts to the general public, they lost this customer (this is the second sea star system I have owned).
Oh, there is ZERO free play in the steering so if you make a turn, you are going to turn. The pivot system is spot on. When ya go to disassemble from the pivot pin on the engine, take the nut off first and THEN unscrew the bolt. DO NOT try to turn the bolt while that nut is still attached because the nut acts as a redundant back up to prevent the bolt from coming loose from the pivot pin. The pivot pin is threaded aluminum. You may have to tap the hole on the pivot pin to a bigger bolt/thread pitch. You have to use the bolt that comes with the kit. Some you do and some you dont. I had to, but it was no big deal.
The play I am talking about is when you grab the back of the motor and pull hard side to side. Every sea star unit I have seen or owned has about 1/8″ of side to side play where you can see the hydraulic ram remain still but the cylinder moves back and forth about 1/8″. Thats enough to trigger chine walking at high speeds.
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