Brake master cylinders

After years of monitoring and posting on the Matronics and Yahoo sites, I finally discovered THIS forum. I just can't keep up ...

Anyway, several builders have replaced the stock brake master cylinder setup with ones that eliminate the brake fluid reservoir on the firewall and all of the associated tubing. I've searched everywhere and can't seem to find the part numbers for the right replacement master cylinders, although I believe people were buying them from Aircraft Spruce or Wicks. Anybody out there know?

And, while on the subject, has anyone made the swap and regretted it? Any chance to simplify systems sounds good to me right now ...

Thanks,

Don McNamara
N8RV

I also came across a reference to cylinders being used, and I think it was on an RV8.
Go to this page at ACS, and I think the ones we're talking about are the model A-600.
http://www.aircraftspruce.com/catalog/lgpages/reservoirs.php

I have yet to find anyone else who's mentioned that they used them but maybe someone will chime in here.

I have them installed, but the plane is still in the basement.

CHeck Randy Lervolds site. He had them on his 8 and liked them a lot

Master cylinders

I've used these units on two different RV-8's and neverhad a problem. They sure eliminate a bunch of plastic tubing.

Here's a direct link to the info on Randy's site.

Dave

I've got them on mine, and my buddy John on his. No problems at all EXCEPT if you have adjustable pedals, the master cylinders might hit the firewall when the pedals are fully forward and at full travel in either direction. Now, I'm 6'4", and I have my pedals set about 2/3 forward travel. Any farther than that and I can't touch them.

Hope this helps,

Brake Reservoir

Don, I've used them on my plane and have had NO problems. Lot's less tubing
and chance to leak. They are P/N A-600 in the Spruce catalog. You will need two. BTW, you started that engine yet ? You gotta get airbourne BUD ! Best Regards, Mark Cigal N617MC ... flyin and lovin it !!

Break Reservoir

If you use the things be sure to limit the travel on the slider so the peddels do not hit the firewall.

I used better tubing instead

I too considered the brake reservoirs on the cyls.....then I got to thinking about servicing and bleeding the brakes (I have a back bleeder setup), and not wanting to get 5606 spilled on my carpet and interior parts, I elected instead to plumb the supply lines with the same hose and AN fittings that are used on the pressure side of the master cyls. I used alum tubing from the firewall-mounted reservoir to bulkhead fittings above the pedals, then the hose down to the supply side of the brake cyls. I'm not flying yet, but at some fly-ins I've seen quite a few builders that did the same thing. Have fun, you can't go wrong with either option.

I have them on my Rocket. I used the old method on my RV-6.

While they are simplier with less parts, they are a giant pain in the arse when it comes time to check the fluid level or to add fluid. It is not very convenient crawling under the panel to try and reach the small plug in the top. I assumed that I would be able to reach them from above by removing the boot cowl, but it's full of avionics and not reachable.

If I were to do it again, I might use the seperate master cylinders and make a short run of tubing up from the cylinder to somewhere above the avionics so I could reach it easier for servicing. I do like the fact that it's one less hole in my firewall and they are easier to bleed, at least for me.

Brake fluid reservoir

I've loved the individual reservoirs mounted on the master cylinders of my Pitts S-2A for years. Ordered similar reservoirs from Aircraft Spruce recently for about $12 each (two req'd, 06-00392 ACS Reservoir A-600). Hoping that servicing will be easy through the front baggage - just take out the floor. I think refilling/bleeding will be much easier and more predictable with this set up, and tidier as well. But I don't plan to have a carpet. We have a Piper Lance (1976) which has been a pain that way - it has a tin can type of reservoir on the firewall. Pedals were severely soft after annual and we went on X-C to Denver (Centennial). The guy there said no prob, we can fix that easy. Came back to find pedals a little firmer but still soft - so was my wallet after $350.00 bill for the bleeding. Thought I could do better and tried - I couldn't. Probably the parking brake and dual brakes complicate the Lance situation. The set up on the Pitts is dead simple to fill/bleed. Aviat's prices were too high for me. I'd go with Spruce. Bill