SeaStar Fluid

Jonah

GreatGrady Captain
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Model
Sailfish
Hi all,

Just checked my SeaStar steering fluid, and it's a bit low. The cap says to use SeaStar fluid only, and I'm wondering how serious that is? I have some Mercury "Power Trim & Steering Fluid", but will gladly buy some SeaStar if anyone recommends it.

Thanks as always.
 
Ha! mine is a little low too. Previous owner had 2 different brands so I guess it don't matter.... Thinking of purging it and filling with new by doing the procedure.... I was looking for the "SeaStar Filler Kit" at West Marine...they want $27.99 for a bottle cap with a clear vinyl hose and a fitting.. :jaw ..I WILL NOT DO IT.

Amazon wants $18...uhg!
 
SkunkBoat said:
Ha! mine is a little low too. Previous owner had 2 different brands so I guess it don't matter.... Thinking of purging it and filling with new by doing the procedure.... I was looking for the "SeaStar Filler Kit" at West Marine...they want $27.99 for a bottle cap with a clear vinyl hose and a fitting.. :jaw ..I WILL NOT DO IT.

Amazon wants $18...uhg!

I plan on pushing new fluid through my steering system in the near future. I had read somewhere (THT?) that a common male air hose chuck fitting is the same size/thread as the SeaStar filler port. If that's the case, it would be easy to clamp on some cheap clear hose and a funnel on the other end to fill the system.
 
It's very easy to rig up a bottle with a fitting and hose from your local hardware store that works. For fluid you can buy it a lot cheaper at your local general aviation airfield repair facility. That's where I bought this. It's the proper fluid specified by Seastar with the exception that it has a red dye in it to meet aviation requirements of identification. The gallon cost me $38.

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Be careful about using aviation hydraulic fluids. There are basically two types: Phosphate ester based fluid (Skydrol) and not to be used, (very caustic) and various brands of Mil H-5606, petroleum based, which is normally dyed red and can be used in SeaStar systems. Check the MILSPEC before buying aviation hydraulic fluid.
 
Jonah said:
Hi all,

Just checked my SeaStar steering fluid, and it's a bit low. The cap says to use SeaStar fluid only, and I'm wondering how serious that is? I have some Mercury "Power Trim & Steering Fluid", but will gladly buy some SeaStar if anyone recommends it.

Thanks as always.

My recommendation again is buy the SeaStar fluid and not mix. I wouldn't take a chance with mixing and have a failure with your steering, it's kind of important underway. I bought 4 quarts and flushed my system when I was topping off mine. Never hurts on a boat with some age. Pick up the fill kit also, it makes life much simpler. You can piece a kit together too if you're handy.
 
I agree with KY Grady that if you haven't serviced the system in several years, flushing the system a bit will help keep things working in good order. If you do bleed/flush the system and read the Seastar how-to literature, somewhere in there I remember it saying not to be too "tentative" about turning the wheel on a manual pump. The rotation speed of the wheel for bleeding air should be no slower than 1 1/2 to 2 seconds per revolution. That creates enough flow to move any air bubbles along the tubing and not allow them to accumulate in a high spot in the tubing. Good luck. It's a fun project and makes a difference if your steering is sloppy or spongy.
 
Nice, thanks everyone. I picked up some (overpriced!) SeaStar fluid from a local shop here, and topped it off. I don't have a trailer, so won't be in a good position to bleed the system for a while. I'll save the extra fluid, and your advice, for whenever I have a chance.

So far, the steering is fine; the fluid just looked a little bit too far below the threads in the helm's fill-hole.
 
I also topped of before launching. only took spit. The 265 still can't go slow in a straight line. Thinking of naming it "Wiggles" or "The Wanderer" :lol:
Guess I'll have to try the full procedure one of these days. Looks like it can be done while floating.
 
SkunkBoat said:
I also topped of before launching. only took spit. The 265 still can't go slow in a straight line. Thinking of naming it "Wiggles" or "The Wanderer" :lol:
Guess I'll have to try the full procedure one of these days. Looks like it can be done while floating.

A previous boat I owned was a "wanderer" at slow speeds also. Something that really helped was to deploy one trim tab fully down. That drag would cause the bow to pull to that side, then a steering correction to offset that pull and hold the bow in the desired direction helped immensely. This became my normal slow speed set-up but you need to remember to retract the tab before jumping on plane to avoid the surprise of a big sudden list when the boat comes on-step.
 
I just changed the fluid in my Seastar system and used Phillips 66 Avation Hydraulic fluid. It meets the specs approved by Seastar as a substitute. It is $5.95 per quart from an outfit called Aircraft Spruce. With shipping it came to $34/gallon. It took a little less than 2 quarts. Although my boat is on a trailer,I did everything from inside the boat. I had a lot of slack in the steering and changing the fluid made a tremendous improvement.
 

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Greyduk said:
I just changed the fluid in my Seastar system and used Phillips 66 Avation Hydraulic fluid. It meets the specs approved by Seastar as a substitute. It is $5.95 per quart from an outfit called Aircraft Spruce. With shipping it came to $34/gallon. It took a little less than 2 quarts. Although my boat is on a trailer,I did everything from inside the boat. I had a lot of slack in the steering and changing the fluid made a tremendous improvement.

I recently replaced my leaking seals at the engine steering unit and then bled the system. I used the Phillips 66 fluid and it works great. I was fortunate enough to buy it from our local airport so it I saved shipping.

Nothing wrong with buying the SeaStar branded fluid if it makes you feel better, but you don't have to.