Seastar hydraulic steering and atf fluid.
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I found a hydraulic jack oil at an autoparts store (Canadian Tire) with the same US milspec as the Seastar oil ... for less than 1/4 of the price. I've been using it for 6yrs now with no problems.
I'd tell you what the milspec number is but the label is so stained it's illegible.
I'd tell you what the milspec number is but the label is so stained it's illegible.
PPandE
Senior Member
The mil spec is 5606 and It is red. It’s used extensively in aircraft and occasionally there is a minor change to the specs resulting in lots of unusable oil stored in the back rooms of airport maintenance hangars. I’ve managed to lay claim to many a gallon for free.
Keysdisease
Guru
Why would you not use Sea Star fluid?
O C Diver
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I had the helm pump and cylinder rebuilt on my Hynautic steering system. The factory authorized rebuilder recommended aircraft hydraulic fluid as the purest, thinnest, and best fluid for the system. $9 per quart from Aircraft Spruce.
Ted
Ted
gulfstar1
Veteran Member
I have a Seastar Capilano 1250V system on my '84 Present 42. It uses Dexron II type ATF fluid as per the manufacturers instructions. I have owned the boat for almost 3 years. So far no steering problems.
I could argue to use aero hydraulic fluid, but that's really a misnomer.
ANY hydraulic fluid with the same MIL spec, is the SAME... there is no "purest" just because it has an aviation label on it. Chevron, Phillips, Shell... all the same. Now there are different dash numbers. Started as 5606, then 5606A, etc., believe the latest is 5606G, however, very little difference and all will work in our boats.
Now, for some reason the aviation suppliers sell it fairly cheap... and not hard to find it in the $25 a gallon range, or where Ted gets it at Aircraft Spruce. If you google it, there are other suppliers.
And occasionally, you may find a local oil distributor that will sell it (and other oil products) very reasonable, especially in bulk.
ANY hydraulic fluid with the same MIL spec, is the SAME... there is no "purest" just because it has an aviation label on it. Chevron, Phillips, Shell... all the same. Now there are different dash numbers. Started as 5606, then 5606A, etc., believe the latest is 5606G, however, very little difference and all will work in our boats.
Now, for some reason the aviation suppliers sell it fairly cheap... and not hard to find it in the $25 a gallon range, or where Ted gets it at Aircraft Spruce. If you google it, there are other suppliers.
And occasionally, you may find a local oil distributor that will sell it (and other oil products) very reasonable, especially in bulk.
Ski in NC
Technical Guru
One boat I ran used ATF. In cold weather the steering was much harder due to higher viscosity. In warm weather it was fine. Flushed it out with 5606 fluid and it was much better. 5606 aero hyd fluid is an absolutely fine replacement for the branded sea star fluid.
Why would you not use Sea Star fluid?
if you don't mind paying 4 or five times more than other products that meet the same spec ..... go for it.
Bkay
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Coincidentally, I was researching this over the weekend.
I came to the conclusion that I will go with milspec PRF-5606 aircraft hydraulic fluid. It is an acceptable substitute per Seastar with the primary difference being red dye (so you can more readily identify leaks). I understand the dye can play hell with gelcoat - but my aluminum boat won't care.
As a totally unrelated note: I found out in my research that PRF in milspec PRF-5606 indicates it meets the "performance" standard of 5606. The Seastar instructions indicate H-5606 which is the outdated specification system no longer in use.
I came to the conclusion that I will go with milspec PRF-5606 aircraft hydraulic fluid. It is an acceptable substitute per Seastar with the primary difference being red dye (so you can more readily identify leaks). I understand the dye can play hell with gelcoat - but my aluminum boat won't care.
As a totally unrelated note: I found out in my research that PRF in milspec PRF-5606 indicates it meets the "performance" standard of 5606. The Seastar instructions indicate H-5606 which is the outdated specification system no longer in use.
I've always just run the SeaStar brand fluid in my SeaStar system on my center console (because it takes so little of it). But, I've used ATF fluid for years in my Hynautic steering System.
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The manual for the 1976 vintage Seastar Capilano 1250V system that came with Sandpiper specifies ATF for fluid.
I've had no issues in 20 years since fluid renewal.
I've had no issues in 20 years since fluid renewal.
Lou_tribal
Guru
If you have a picture of the jug I would be interested having canadian tire nearby.
Thank you
L
sean9c
Guru
Tony at Seaboard Marine recommends 3 parts ATF and 1 part #2 diesel. Guessing that the #2 reduces viscosity a little and adds some lubricity.
Keysdisease
Guru
Had the same qt bottle aboard for 11 years, not something I buy like beer. I know Sea Star / Teleflex do not refine oil, they buy it from an oil company and brand it. And yes, the equivalent/same in several industries is the same stuff.
I worked for a company that manufactured and sold a hydraulic system. The system, tolerances, performance and seals were designed for a specific oil, in this case the readily available and cheap ATF. Did not stop people from calling and asking if they could use this or that.
Capilano and Sea Star (Teleflex) are from the same manufacturer, but specify different oils for their systems. Same with Wagner and Hynautic, and within the Hynautic line different oils for steering than their controls.
Unless I'm going through gallons of the stuff, for stand by / back up in case of a leak, I tend to stick with the manufacturers recommendation.
If the difference was hundreds of dollars and it cost 4 or 5 times as much, I might shop around.
$0.02
rslifkin
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I worked for a company that manufactured and sold a hydraulic system. The system, tolerances, performance and seals were designed for a specific oil, in this case the readily available and cheap ATF. Did not stop people from calling and asking if they could use this or that.
In some of those cases, it may have been a commonality question. And at least they asked, instead of trying it and breaking stuff... I've been known to vary fluids slightly in automotive applications just to reduce the number of different fluids I have to keep around. And occasionally I've found a functional benefit from it (such as switching a power steering system that said to never use ATF to ATF, which improved cold weather performance and caused no issues at all in over 100,000 miles).
OP
OP
Pmcsurf1
Senior Member
We bought a new Garmin system with auto pilot. Reactor 40 and the such. Installer left the plastic caps in the pump. During sea trial all the fluid leaked out and we lost steering. Had to add fluid on the hook to get back. Oil was dripping everywhere as the pump was installed in the upper helm. Picture of the pump shows the oil straying out while turning the helm.
OP
OP
Pmcsurf1
Senior Member
Btw. Garmin guy made many more mistakes during install. Very poor job. We're in negotiations about his bill. I leaning towards paying for parts and not paying for labor. We're still cleaning oil from leaks seeping oil all over the boat. I also reinstalled the pump. Original installer mounted screws though our outside gell coat. Left all the old Raymarine wiring, still hot and sparking/arching. Didn't even cap off the old wires. Total cluster. Btw. Local garmin dealer with all the certificates on the wall.
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I'd deduct your time for clean up from the parts on the bill in addition to not paying labor.
Make sure to take lots of pictures for documentation in case of push back from installer.
Write up a detailed description of what happened, what was said etc while fresh on your mind. Written report holds a lot more evidentiary weight than memory recollection.
Every time I have a beef with vendors, I email vendor my report and tell them that I'm giving then an opportunity to respond before I send the report to Boat US, Passagemaker Magazine and the local boating magazine; NW Yachting. I've been very successful at getting satisfaction.
The label is truly illegible but just go to CTC and look for the black 1 quart bottle of hydraulic jack oil marked with the 5606 US milspec.
Had the same qt bottle aboard for 11 years, not something I buy like beer. I know Sea Star / Teleflex do not refine oil, they buy it from an oil company and brand it. And yes, the equivalent/same in several industries is the same stuff.
I worked for a company that manufactured and sold a hydraulic system. The system, tolerances, performance and seals were designed for a specific oil, in this case the readily available and cheap ATF. Did not stop people from calling and asking if they could use this or that.
Capilano and Sea Star (Teleflex) are from the same manufacturer, but specify different oils for their systems. Same with Wagner and Hynautic, and within the Hynautic line different oils for steering than their controls.
Unless I'm going through gallons of the stuff, for stand by / back up in case of a leak, I tend to stick with the manufacturers recommendation.
If the difference was hundreds of dollars and it cost 4 or 5 times as much, I might shop around.
$0.02
I did stick with the mfg's recommendation .... Milspec 5606. I just paid a helluva lot less for it. I dislike being gouged.
Lou_tribal
Guru
Me too... When we first got our boat on our way home I found a tiny leak at the cylinder that emptied half of the upper helm pump. On Rideau waterway we spent a night at a lock where there was a boat shop nearby. Went there to get a quart of hydraulic fluid to play it safe on the way back. It cost me 42$ plus taxes for a quart of seastar juice, I felt sort of a pain...
L
Agreed ! I refuse to pay a 460% premium for their name on a label.
5606 is some great stuff. Used it in aircraft for years and got a "wild hair" once when rebuilding the clutch master and slave cylinder on a 1969 Triumph Spitfire. Apparently the seals are a non-5606 compatible rubber of some type and the 5606 turned them into mush. The clutch felt great the first few tests after the rebuild, but went to hell in a handbasket quickly. My lesson, test its compatibility with seals thoroughly before using in an application outside of aviation...
After another, and very difficult, rebuild I used the proper brake fluid for the clutch system!
After another, and very difficult, rebuild I used the proper brake fluid for the clutch system!
C lectric
Guru
My hydr. steering was made by Wagner, now out of business. The instructions said ATF, the GM stuff for which I don't remember the specific name. I used it to refill the system after I resealed the steering cylinder. The reseal was done ~ 25 or so years ago. No leaks, no problems so far.
We get freezing in winter and we used to boat in winter freezing conditions and I never noticed any stiff steering.
I do have a spare cylinder which got a reseal a couple of years ago awaiting any leaks at the installed cylinder..
We get freezing in winter and we used to boat in winter freezing conditions and I never noticed any stiff steering.
I do have a spare cylinder which got a reseal a couple of years ago awaiting any leaks at the installed cylinder..
my boat is from Canada, now i must learn, to check all these systems for empty liquid in boat. we don't have this and don't need in MED. Somtime in winter on see temperature drop to 15°C ,close river maybe 12C in air maybe we have -4 every 10 year 1 day or couple max. but not in sea because sea is around 15-16°C
bajajohnny
Member
I’ve been using ATF dextron three mixed with diesel at a three to one ratio… Three parts ATF one part diesel for years instead of Seastars overpriced hard to find oil.
Seastar don't produce oil, hi simply from prepack from big drum to small bottle.
also in USA iso vg 15 oil is cheaper ws EU.
ISO VG 15 High Viscosity Index (HVI) Hydraulic Oil
from 10$ gallon is nothing after open factory say 6 year /read 10 year but also in system you must every 800-1000 hour exchange oil
also in USA iso vg 15 oil is cheaper ws EU.
ISO VG 15 High Viscosity Index (HVI) Hydraulic Oil
from 10$ gallon is nothing after open factory say 6 year /read 10 year but also in system you must every 800-1000 hour exchange oil
