Vitron o-ring and higher temp brake fluid

[drmax]

Anyone using the Vitron seals on the cleveland brake pucks with the higher temp oil? I found one member Jim Freeman who posted one time (2007)and said he used it on his RV8. I need more info. Thx, DM

[db1yg]

DM,

Sure---made the conversion about 18 months ago. Used the Viton o rings and, if I remember correctly, Mobil one ATF. Works great, no problems and it provides a much higher margin for flash.

Cheers,

db

[RV6_flyer]

I have been using them for several years. I purchased 100 of them and shared them with the local RVs around me. They were a buck a piece when you buy 100.

I followed the info from Randy Lervold's RV-3 web site.

There is also info on the Mil Spec brake fluid.

[flyeyes]

The "higher temp" hydraulic fluid is MIL-H-83232 also called Royco 782

It is chemically compatible with the "normal" 5606 fluid that most GA airplanes use for brakes and hydraulics. You can top off one of the fluids with the other in a pinch, but the mixture will have qualities of each. For example, a 50/50 mix of 5606 and 83282 will have a flash point about halfway between the flashpoints of the individual fluids.

The Viton O-rings are a standard industrial supply item available pretty much anywhere you can buy O-rings. They tolerate much higher temperatures than the stock nitrile seals, and remain compatible with the 5606 and 83282.

I know some have used ATF, but I don't have any experience with that.

When you change the o-rings, essentially all of the 5606 fluid will drain out. Since it is entirely compatible, I have just refilled from the bottom (using one of those little pump cans from Harbor Freight) with 83282.

I have made these changes on 5 RVs now, with no issues on any that I'm aware of with several hundred hours and landings in aggregate.

[drmax]

Originally Posted by flyeyes

The "higher temp" hydraulic fluid is MIL-H-83232 also called Royco 782

It is chemically compatible with the "normal" 5606 fluid that most GA airplanes use for brakes and hydraulics. You can top off one of the fluids with the other in a pinch, but the mixture will have qualities of each. For example, a 50/50 mix of 5606 and 83282 will have a flash point about halfway between the flashpoints of the individual fluids.

The Viton O-rings are a standard industrial supply item available pretty much anywhere you can buy O-rings. They tolerate much higher temperatures than the stock nitrile seals, and remain compatible with the 5606 and 83282.

I know some have used ATF, but I don't have any experience with that.

When you change the o-rings, essentially all of the 5606 fluid will drain out. Since it is entirely compatible, I have just refilled from the bottom (using one of those little pump cans from Harbor Freight) with 83282.

I have made these changes on 5 RVs now, with no issues on any that I'm aware of with several hundred hours and landings in aggregate.

Hello. There was mention of either a v75 and v90, which the 75 is softer. I just ordered 6 of the 75's. Going to do both brakes this weekend. Thank you for the info. DM
thank you

[Vac]

AVIATION BRAKE FLUID SPECIFICATIONS:

Petroleum-based:
(1) Mil-H-5606: Mineral base, flammable, fairly low flashpoint, usable from −65 ?F (−54?C) to 275 ?F (135?C), red color
(2) Mil-H-83282: Synthetic hydrocarbon base, higher flashpoint, self-extinguishing, backward compatible to -5606, red color, rated to −40?F (−40?C) degrees.
(3) Mil-H-87257: A development of -83282 fluid to improve its low temperature viscosity.

MIL-H-83282 replaces MIL-H-5606. It is dyed red so it can be distinguished from incompatible fluids. MIL-H-83282 has a synthetic hydrocarbon base and contains additives to provide the required viscosity and anti-wear characteristics, which inhibit oxidation and corrosion. It is used in hydraulic systems having a temperature range of -40 deg F to 401 deg F (-40?C to +205?C). Flash point (445 deg F), fire point (490 deg F), and spontaneous ignition temperature of MIL-H-83282, which is fire resistant, exceeds that of MIL-H-5606 by more than 200?F. The fluid extinguishes itself when the external source of flame or heat is removed. Hydraulic fluid MIL-H-83282 is compatible with all materials used in systems presently using MIL-H-5606. It may be combined with MIL-H-5606 with no adverse effect other than a reduction of its fire-resistant properties.

Royco 782 and Aeroshell Type 31 hydraulic fluid meet MIL-H-83282.

BRAKE CALIPER O-RINGS

This information applies to the stock, Van's supplied Cleveland 30-9 brake caliper assemblies:

Each caliper is fitted with an o-ring. The FAA-approved Buna rubber (nitrile rubber, V70 hardness rating) ring is AN6227B-23 or MS 28775-218 for certified installations. These rings, however, have a maximum temperature rating of only 250 deg F. If used in conjunction with Mil-H-5606 hydraulic fluid, brake failure and fire is possible if caliper temperature exceeds approximately 250 deg F. The caliper o-rings may be replaced by Viton (synthetic rubber) rings rated to 400 deg F. Different grades of Viton rings are made, with the most important difference being low-temperature performance. The most typical types (e.g., Viton-A, conforms to Mil-R-83248) are rated to -15 deg F, however Viton GLT (conforms to Mil-R-83485) is rated to -31 deg F and should be considered for low-temperature operations. Viton-A rings with a hardness rating of V75 are sufficient for this application. V90 rings or low-temperature GLT (V-115) may be substituted. Rings should be obtained from a reputable aerospace supplier, properly documented and be made of 100% virgin materials. The -218 ring size dimensions are 1 ?? ID x 1 ?? OD x 1/8? CS (cross-section).

If you only make one modification, consider substituting the o-rings since that is the "weak link" in this mishap chain (i.e., prevent the leak in the first place). To swap fluid, a 100% flush should be performed if you want the "high temp" fluid to work to specification.

Cheers,

Vac

[Ron Lee]

Can a moderator change the "oil" in the subject line to "brake fluid" to help in future searches of this topic?

[Done. S.Buchanan]

[drmax]

Originally Posted by Vac

AVIATION BRAKE FLUID SPECIFICATIONS:

Petroleum-based:
(1) Mil-H-5606: Mineral base, flammable, fairly low flashpoint, usable from −65 ?F (−54?C) to 275 ?F (135?C), red color
(2) Mil-H-83282: Synthetic hydrocarbon base, higher flashpoint, self-extinguishing, backward compatible to -5606, red color, rated to −40?F (−40?C) degrees.
(3) Mil-H-87257: A development of -83282 fluid to improve its low temperature viscosity.

MIL-H-83282 replaces MIL-H-5606. It is dyed red so it can be distinguished from incompatible fluids. MIL-H-83282 has a synthetic hydrocarbon base and contains additives to provide the required viscosity and anti-wear characteristics, which inhibit oxidation and corrosion. It is used in hydraulic systems having a temperature range of -40 deg F to 401 deg F (-40?C to +205?C). Flash point (445 deg F), fire point (490 deg F), and spontaneous ignition temperature of MIL-H-83282, which is fire resistant, exceeds that of MIL-H-5606 by more than 200?F. The fluid extinguishes itself when the external source of flame or heat is removed. Hydraulic fluid MIL-H-83282 is compatible with all materials used in systems presently using MIL-H-5606. It may be combined with MIL-H-5606 with no adverse effect other than a reduction of its fire-resistant properties.

Royco 782 and Aeroshell Type 31 hydraulic fluid meet MIL-H-83282.

BRAKE CALIPER O-RINGS

This information applies to the stock, Van's supplied Cleveland 30-9 brake caliper assemblies:

Each caliper is fitted with an o-ring. The FAA-approved Buna rubber (nitrile rubber, V70 hardness rating) ring is AN6227B-23 or MS 28775-218 for certified installations. These rings, however, have a maximum temperature rating of only 250 deg F. If used in conjunction with Mil-H-5606 hydraulic fluid, brake failure and fire is possible if caliper temperature exceeds approximately 250 deg F. The caliper o-rings may be replaced by Viton (synthetic rubber) rings rated to 400 deg F. Different grades of Viton rings are made, with the most important difference being low-temperature performance. The most typical types (e.g., Viton-A, conforms to Mil-R-83248) are rated to -15 deg F, however Viton GLT (conforms to Mil-R-83485) is rated to -31 deg F and should be considered for low-temperature operations. Viton-A rings with a hardness rating of V75 are sufficient for this application. V90 rings or low-temperature GLT (V-115) may be substituted. Rings should be obtained from a reputable aerospace supplier, properly documented and be made of 100% virgin materials. The -218 ring size dimensions are 1 ?? ID x 1 ?? OD x 1/8? CS (cross-section).

If you only make one modification, consider substituting the o-rings since that is the "weak link" in this mishap chain (i.e., prevent the leak in the first place). To swap fluid, a 100% flush should be performed if you want the "high temp" fluid to work to specification.

Cheers,

Vac

VERY NICE, Vac!!!!
BTW...I've asked a fella by the name of Mike from Spruce to investigate adding these items to their inventory. He replied back with an email basically stating..."I'm on it".
DM

[drmax]

Hello. Will any old brake pump tool/kit work on the cleveland brakes, such as this from harbor freight?
http://www.harborfreight.com/automot...kit-69328.html
I want something I can pick up locally, which they are near. If this isn't correct please advise as to what I need.
Thx, DM

[GWZ]

Originally Posted by drmax

Hello. Will any old brake pump tool/kit work on the cleveland brakes, such as this from harbor freight?
http://www.harborfreight.com/automot...kit-69328.html
I want something I can pick up locally, which they are near. If this isn't correct please advise as to what I need.
Thx, DM

Hi DR, I ended up buying a 9A too. Have about 40hrs on it so far. Generally it's best to push the fluid up through the caliper then out the reservoir. You can still shop at HF though I bought a cheap oil squirt can. fill it with brake fluid and connect it to your bleeder valve with a short length of hose. I adapted a small hose barb to screw into the the top of the reservoir. attach a hose to that that goes to a catch can and start pumping until the hose connected to the reservoir flows without bubbles. It wouldn't hurt to look at the lines from you master cyl (rudder pedals) to the reservoir to make sure no air is left in them. depending on how they are routed they may trap a bubble (those shouldn't hurt but I always liked to get them out.)
Also don't worry about heavy braking on your airstrip, I can already land my 9A in such a short distance sometimes I have to throttle up to taxi to the first turnoff and with only 40hrs in the 9A I'm a newbie! I just put on new pads and I expect they will last a loooog time.
GZ