Re: Defiant leaky brakes
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My experience is with single puck Clevelands on my LongEz. My brakes use the MS28775 O-rings in a slightly smaller size. However, I replaced the originally spec'd Buna-N O-rings for Viton O-rings. Viton has superior high heat tolerance. When I did my research, others had reported contacting Parker-Hannifin and the tech there had no issues against using Viton.
Did you verify if the leak is from the O-ring, the bleeder, or the fittings? I suppose you use silicone based brake fluid because it is not hygroscopic and less flammable than the standard aviation 5606 fluid. Maybe that is why you have leaks since the system is designed for the standard fluid, not the DOT5. In my opinion, aircraft should not use DOT5 because it is not compatible (miscible) with the standard red fluid and, if getting help from an A&P away from home base, he may add standard fluid and cause a bad situation for you. I use a less common, but compatible aviation fluid, spec'd as #83282. Its also known as Aeroshell #31 or Rayco #782. It is red, 100% compatible with the standard 5606 aviation brake fluid, but has a much higher flash point.
On Sun, Jul 7, 2019, at 2:39 PM, john toelaer johntoelaer@... [canard-aviators] wrote: