Sea Star Hydraulic pump leaking fluid repair.

Rockfish

Well-Known Member
Our rear transom mounted helm pump was starting to sweat a little fluid under the steering wheel. We repaired it yesterday and it was an easy job, so if anyone is having a similar problem this is encouragement to give it a try.

The helm was mounted on the transom facing up and has a small 7 inch or so Aluminum steering wheel. We replaced just the outer helm seal about 6 years ago and the most difficult part was getting the nut off and the wheel off the shaft. When we reassembled we greased the hell out of everything which really helped disassembly this time.

This time we bought the actual Sea Star Service kit which supports a partial rebuild of the pump not just a new seal. It contained a new shaft nut, cover plate, three cover plate mounting screws, shaft key and the outer shaft seal.

First we spayed the nut and wheel hub with penetrating oil and left it for a couple of hour while we installed a new duel horn signalling device on the front of the boat and went for lunch.

Then we wedged a standard pry bar under the lip of the wheel and against a wheel arm and the other end wedged against the angled back of the transom with a thick piece of plastic under it to protect the gel coat. This is necessary, as without wedging the wheel, when you try to remove the shaft nut the whole wheel will just spin.

Next we removed the shaft nut on the outside of the wheel with a breaking bar attached to a large impact socket.

Then a large three arm gear puller was used to remove the steering wheel while applying equal downward pressure on the shaft. Never just pry or hammer on the wheel as that could do serious damage to the pump.

Once the wheel is off, gently tap the ends of the pressure fitted key in the side of the shaft to loosen it and remove it with slip joint pliers.

Remove the three retaining screws holding the plastic cover and the cover.

Then we lubed the new seal and got ready to replace it. We prepared a bunch of paper towels and were ready to move fast as this is the lower of the two helms so once you pull the seal, even with the pump facing up, gravity is going to flow a fair bit of fluid out of the system around the shaft. We used a small screwdriver to pry out the old seal and the wad of paper towels to soak up the releasing fluid while we pressed the new seal back in using only our fingers so as not to damage the seal.

We then reassembled using all the new parts and tightened the nut to the specified torque noted in the kit. We wiped everything down and finally topped up the fluid reserve at the upper helm station. In a duel helm system, never remove the cap on the lower helm to add fluid as gravity will pour fluid out all over the boat.

Other than waiting for the penetrating oil to do its magic the whole job took about 17 minutes and the cost of the Sea Star service kit was a little over $13.00. If you ever notice fluid starting to sweat/leak out under the steering wheel, I hope this helps. It is an easy do it yourself fix.
 
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Good info. on that note, if your hydraulic cylinder ever leaks at the motor, don't buy the crazy expensive 150$ replacement kit. i just bought the seals and the wipers seperately from a hydraulic shop (Vp systems for me in victoria) and they were about 18$. Just show them the attached image and you are set. You will need the wrench, which is the same as the trim rams on a Yamaha V6s BTW. the one i have is this one: https://marinetechtools.com/pin-spanner-wrench-38mm-x-4mm.html (the one yamaha makes is garbage and even the dealers refuse to sell them)
 

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