What fluid.
- Thread starter Comoshun3
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Portage_Bay
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I don't know if you an add Seastar fluid. Probably but I'm not sure. I called a local airport serving private and small biz aircraft and found the mil spec 5606 for if I remember correctly about $29 a gallon. Far cheaper than Seastar.
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z1nonlyone
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My hydrulic steering specifies Hynautic Steering Fluid. Since this is hard to find I too am looking for another type. I read the label on the original gallon jug I have of Hynautic steering fluid and it says that automatic steering fluid can be substituted but it may make the steering feel slightly stiffer.
Alaskan Sea-Duction
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I have a Hynautic system. They recommend the same mil spec. This is the fluid I use. You can find it online.
HTurner
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GoneFarrell
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5606 is 10W hydraulic system oil that has been processed to dewax the oil for aircraft use at low temperatures. Keeps things from getting sluggish and clogged at low temps (-40). Good stuff. I used it in hydraulic equipment that had to function in an ice cream freezer warehouse at 40 below.
Another source might be a tractor store or Cat dealer, John Deere dealer.
Just a quick search I see AeroShell 41 at $8.75/quart. Lots of sources for this stuff.
Another source might be a tractor store or Cat dealer, John Deere dealer.
Just a quick search I see AeroShell 41 at $8.75/quart. Lots of sources for this stuff.
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Bkay
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I looked this up recently and will try to recall the key details.
Seastar can be substituted with MIL-PRF-5606H (the "H" is apparently for hydraulic). You should avoid using 5606A as the "A" product is not superclean as is the "H" (and presumably Seastar). I believe the superclean product is necessary to prevent wear.
I had a hard time finding 5606H in a resealable container that would allow me to use just a small amount to top up - you either used the full container or wasted the leftover. I asked someone why I could find "A" in a resealable container but no "H" and they said "if you leave the open container sitting around it won't be super-clean anymore, now will it?" Whatever...
https://meridian-oil.com/assets/dow...6H_and_XC_5606A_Aviation_Hydraulic_Fluids.pdf
By the way, MIL-H-5606 is the old designation. You want the current MIL-PRF-5606H. The current designation indicates the fluid meets a performance standard of 5606 (thus "PRF").
Seastar can be substituted with MIL-PRF-5606H (the "H" is apparently for hydraulic). You should avoid using 5606A as the "A" product is not superclean as is the "H" (and presumably Seastar). I believe the superclean product is necessary to prevent wear.
I had a hard time finding 5606H in a resealable container that would allow me to use just a small amount to top up - you either used the full container or wasted the leftover. I asked someone why I could find "A" in a resealable container but no "H" and they said "if you leave the open container sitting around it won't be super-clean anymore, now will it?" Whatever...
https://meridian-oil.com/assets/dow...6H_and_XC_5606A_Aviation_Hydraulic_Fluids.pdf
By the way, MIL-H-5606 is the old designation. You want the current MIL-PRF-5606H. The current designation indicates the fluid meets a performance standard of 5606 (thus "PRF").
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Portage_Bay
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I have been told by a knowledgeable source that the difference is not in the cleanliness of the oil but in the packaging. The 'A' product is as clean as the 'H' product when packaged and sealed. The difference is that the 'H' packaging is non-resealable, the unused portion is to be discarded. The 'A' product can be purchased in a screw top gallon can. It's up to me to keep my oil clean. My source is the owner / manager of an aviation services shop.
