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Thread: Another brake question

  1. #1

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    Another brake question

    So I have established that I have standard brakes on the PA18-150, with an original rubber diaphragm (thanks all for the help in the other thread). I do have ABI/Cleavland double piston brakes. 6" ABI rims.

    Given that we will be soon running ABW 31's, and regularly landing at conservative off field destinations, at mostly close to max weight, I don't think standard will do it.

    After some research, this is what I think I know are my options.


    • ABI upgrade at about $500
    • Stevesaircraft upgrade at about $800, same as above, but has the added advantage of a fluid reservoir
    • Dakota High-pressure brake master cylinder kit; Note: J3 s/n 10339 for about $1400 (I assume that the extended version is not STC'd).
    • Beringer - would mean replacing wheels and master cylinders and I am guessing very expensive. Also, again I assume using brake fluid instead of 5606 hydraulic.


    So my questions are.

    Are the above, my only valid options?

    Do the Dakota's have a performance benefit over the ABI and Steves?



  2. #2
    Crash, Jr.'s Avatar
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    The Airframes/North River boosters are quite a bit different than Steve's. The North River boosters are a sealed system like stock so the pedal stroke pressurizes the entire system including the "reservoir" when you press the pedal. The Steves are a vented system which means the initial part of the pedal stroke blocks off the incoming fluid from the reservoir and pressurizes only the downline fluid.

    The sealed systems are simpler and lighter by a small margin and much smaller however any changes in fluid volume either by a fluid leak or temperature change causing the fluid to expand or contract can have a large effect on the brakes. That means servicing the brakes more often or you'll suddenly find them ineffective if you have a leak or the fluid contracts and you pull air into the system. I really like mine but I make sure to top them up every 2-3 months. If the brakes start dragging or locking up when it gets hot then you just let some fluid out of the bleeder. Main thing is it's cheap. A lot cheaper than any other option.

    The Steves are vented so they basically just self-bleed if fluid volume changes. Great, very maintenance free and you get consistent pedal feel. Downside is they can be finnicky to bleed the first time because they have an extra bleed point at the front of the cylinder and they are extremely big for what they are. Almost twice as long as the North River boosters. Another downside is they have a little more pedal travel to get to the braking point because the piston has to move further to start pressurizing the downstream fluid.

    Dakotas are just really nice North River boosters basically. A sealed system with a much larger reservoir. Same deal as North River but you just have to bleed them and top them off less often.

    Beringer is absolutely the best but also a LOT of money. If you were upgrading and needed new wheels and brakes as well as master cylinders they would be a good option but since you already have 6" wheels it's a pretty expensive option.
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  3. #3

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    I know several pilots that have done a quality check on the Airframes/Northriver boosters and proven that they can easily put a cub upside down with 31 inch tires. If your parts are in good shape, no wallowed out holes in the peddles or cracks the Airframes is good bang for the buck. Replace the lower screws with Allen cap screws makes it easy to go back together. I usually can go 20 hours before I need to add/check fluid (10 min job) stuff a rag in the floor holes so you do not drop the cap. Use pump can or squeeze bottle to top off. DENNY
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  4. #4

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    I have run everything but the Beringers. Any good braking system will put you on your nose if you slam on the brakes at low speed.
    I would go with Steve's. I am running the Grove equivalents (field approved) and have been delighted for maybe a decade!
    Closed systems are ok if you do not ride the brakes. For those who do, we have to let out a teeny bit of fluid on hot days.
    And while I prefer Dot 5 fluid, the price has gone up tenfold and I will be converting back to 5606 once my present supply runs out.

  5. #5
    Gordon Misch's Avatar
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    I have the Steve's Aircraft masters on my -12. Well made and trouble-free. I have Groves for an experimental I'm working on. They're excellent workmanship, but they're a smaller piston diameter than Steve's or North River, so should probably be matched to Grove wheel units.
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  6. #6
    skywagon8a's Avatar
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    This is an add on brake reservoir for the North River/Airframes master cylinder. To add or remove fluid from the system, just open the ball valve, cycle the pedal and close the valve. Simple, and can be done in flight if needed.

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    N1PA
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  7. #7
    Steve Pierce's Avatar
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    Quote Originally Posted by Crash, Jr. View Post
    Dakotas are just really nice North River boosters basically. A sealed system with a much larger reservoir. Same deal as North River but you just have to bleed them and top them off less often.
    Dakota Brakes are not sealed, they are vented and nothing like the North River brake system. Use the extended reservoirs on big tires and they are part of the STC. The Dakota brakes give you everything new where as the Steve's brakes use your old frames which the castings have been prone to cracking. As far as pedal travel, I have changed out a lot of stock brakes to Steve's and not noticed any pedal travel differences. There is an adjuster between the pedal and the piston to take out the play.
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    Last edited by Steve Pierce; 09-02-2021 at 06:22 AM.
    Steve Pierce

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  8. #8
    Steve Pierce's Avatar
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    Quote Originally Posted by skywagon8a View Post
    This is an add on brake reservoir for the North River/Airframes master cylinder. To add or remove fluid from the system, just open the ball valve, cycle the pedal and close the valve. Simple, and can be done in flight if needed.

    Click image for larger version. 

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    I remember looking at an L21on a west Texas ranch years ago that had a Prince albert can on the side panel plumbed to two valves and the cylinders like yours, ingenious.
    Steve Pierce

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  9. #9
    Crash, Jr.'s Avatar
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    Quote Originally Posted by Steve Pierce View Post
    Dakota Brakes are not sealed, they are vented and nothing like the North River brake system. Use the extended reservoirs on big tires and they are part of the STC. The Dakota brakes give you everything new where as the Steve's brakes use your old frames which the castings have been prone to cracking. As far as pedal travel, I have changed out a lot of stock brakes to Steve's and not noticed any pedal travel differences. There is an adjuster between the pedal and the piston to take out the play.
    Click image for larger version. 

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    Thanks for the correction but I'm going to have to disagree here. And yes, I'm well aware of the differences in construction as I have both North Rivers and Dakotas on two different planes and yes, they are identical in function if not form.

    I'm pretty sure they are NOT a vented system as the cylinder is too short to allow full throw for a vented type of piston arrangement. The Dakotas also use a pressure bearing cap for the reservoir which is a giveaway that they are a sealed system. Vented systems are just that, vented. The cap for the reservoir on a vented system has to have a pressure vent or a diaphragm to prevent vapor lock in the reservoir.
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  10. #10
    Steve Pierce's Avatar
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    Quote Originally Posted by Crash, Jr. View Post
    Thanks for the correction but I'm going to have to disagree here. And yes, I'm well aware of the differences in construction as I have both North Rivers and Dakotas on two different planes and yes, they are identical in function if not form.

    I'm pretty sure they are NOT a vented system as the cylinder is too short to allow full throw for a vented type of piston arrangement. The Dakotas also use a pressure bearing cap for the reservoir which is a giveaway that they are a sealed system. Vented systems are just that, vented. The cap for the reservoir on a vented system has to have a pressure vent or a diaphragm to prevent vapor lock in the reservoir.
    Maybe you should call Dakota Cub. The plug is vented and the top is the reservoir. I have these brakes on my Super Cub. Have been at Dakota and watched them assembled and am pretty sure I know what I posted is correct
    Steve Pierce

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  11. #11
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    Quote Originally Posted by damiens View Post
    So I have established that I have standard brakes on the PA18-150, with an original rubber diaphragm (thanks all for the help in the other thread). I do have ABI/Cleavland double piston brakes. 6" ABI rims.

    Given that we will be soon running ABW 31's, and regularly landing at conservative off field destinations, at mostly close to max weight, I don't think standard will do it.

    After some research, this is what I think I know are my options.


    • ABI upgrade at about $500
    • Stevesaircraft upgrade at about $800, same as above, but has the added advantage of a fluid reservoir
    • Dakota High-pressure brake master cylinder kit; Note: J3 s/n 10339 for about $1400 (I assume that the extended version is not STC'd).
    • Beringer - would mean replacing wheels and master cylinders and I am guessing very expensive. Also, again I assume using brake fluid instead of 5606 hydraulic.


    So my questions are.

    Are the above, my only valid options?

    Do the Dakota's have a performance benefit over the ABI and Steves?


    What's more important to you? Do you want an upgrade for less dollars or do you want a vented system for less day to day maintenance?

    Web
    Life's tough . . . wear a cup.

  12. #12
    Steve Pierce's Avatar
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    Happen to have all of this sitting here in my hangar.
    North River brake master cylinder as installed by Airframes Alaska. I have maintained this airplane since it was rebuilt in 2014. Brakes are always soft when it comes in for annual, I top them off and they work great. Not hard to do just a pain sometime.
    Click image for larger version. 

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    Cub Crafters brake cylinders which were copied off the North River brakes. This is a Cub Crafters rebuild. I have replaced 6 or 8 sets of these with Steve's because owners got tired of adding fluid.
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    Excuse the dog hair and grunge, this is my Super Cub with Dakota Cub brakes installed. I use them on all my rebuilds. They replace the entire brake master cylinder. These have the extended reservoirs given to me by Mark Erickson owner of Dakoat Cub when I stopped at his shop with the new to me airplane and he discovered I was going to install Bushwheels and I had the standard reservoirs.
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    Here is the vented plug that Dakota Cub drills themselves and has anodized blue. Again, excuse the dog hair, they go almost everywhere I do.
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    And I included an old set of installation instructions and assembly drawings of the inner workings of the Dakota Cub mater cylinders for comparison.
    Attached Files Attached Files
    Steve Pierce

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  13. #13
    Crash, Jr.'s Avatar
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    Looks like a regular AN913-1D that's "drilled" for safety wire, not a vent. At least that's what my brakes have. No vent hole, just a safety wire hole.

    *edit* I stand corrected. Dakota says they are a vented type of brake. They don't have a vent hole but somehow the small reservoir works with that. I've still had to top mine up at least once a year or they go flat. I wouldn't say they are much more maintenance free than North Rivers.
    Last edited by Crash, Jr.; 09-02-2021 at 01:11 PM.

  14. #14
    Steve Pierce's Avatar
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    Quote Originally Posted by Crash, Jr. View Post
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    Looks like a regular AN913-1D that's "drilled" for safety wire, not a vent. At least that's what my brakes have. No vent hole, just a safety wire hole.

    *edit* I stand corrected. Dakota says they are a vented type of brake. They don't have a vent hole but somehow the small reservoir works with that. I've still had to top mine up at least once a year or they go flat. I wouldn't say they are much more maintenance free than North Rivers.
    My experience varies. I maintain 20 some odd Super Cubs with all different brakes and all I generally do with DC brakes is check that the fluid level is good and every few years I might add some. Also pull the plug next time you are at your airplane and I think you will find it is a vent. I lost one and had to steal one off my display brake. Had a specific conversation with Mark one day while he was making these vented plugs.

    One thing anyone who has been here a while has figured out about me is I don't post if I don't know what I am talking about. I have been an A&P for over 30 years and actively making my living on these type airplanes for going on 25 of those years. If you post something, no matter who you are that I know is wrong I will correct it. Not to make you look bad but because someone might take what you say to the bank and they will be misinformed. Sorry if this offends, I can go away and spend my time working and keep what I have learned to myself
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  15. #15
    windy's Avatar
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    Another brake question

    Steve Pierce is correct in his statements about Dakota Cub brakes. I have had DC brakes on my PA-12 for 10 years. They are indeed vented. I rarely have to add brake fluid, at most a tablespoon at the annual.
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  16. #16
    Crash, Jr.'s Avatar
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    No offense taken, but I hope you don't take offense if someone questions something that you correct them on. Seems like a lot of folks tend to stay quiet as to not accidentally say something wrong and be corrected on here and that limits discussion. Guess with that I'll leave it to you to talk brakes.

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    Steve, I love the pictures of your Cub vs your customers airplanes! After we rebuilt mine, the first time I went to throw a bunch of muddy, wet fishing gear and fish in the back I hesitated for about one second... Then I smiled and threw it in.....
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    damiens, I have the Airframes/North River boosters in my super cub. They work good, no plans to change them out. I added the Airframes boosters because stock masters would not hold the plane for runup or tight turns, as in 180 turns at the end of narrow strip. I was concerned i would bend up the pedals. Yes, I do have to add fluid on occasion but its easy to do. I learned my lesson, I will go with Dakota or Steve's next time.

  19. #19
    mvivion's Avatar
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    My vote is ABSOLUTELY for vented brakes. A Cub Crafters rebuilt SC with their sealed brakes bought me a 709 ride. Temp was -20 or so. Mechanics took plane off floats and installed wheels. Owner taxied plane to (outside) parking. He called mechanic and said left brake is soft.

    Mechanic went out and topped off left brake reservoir.

    All that was unknown to me. I climbed in back to do FR with owner. That plane has a GREAT cabin heater…..the primary outlet of which pointed right at that left brake reservoir.

    We took off, flew a bit, and came to A/P to do landings. Pilot was sharp, straight as a string. As we climbed from first landing, I noticed the left wheel stopped pretty quick after takeoff…..draggy brake.

    Next landing, she went round. That left brake was locked up tight.

    The FAA, bless them, called the mechanic, and said put it in your hangar, we’ll look at it Monday.

    of course, the left brake functioned fine on Monday in a nice warm hangar.

    I put Steve’s brakes in my Cub, and would so so again. I grant you, the above scenario was pretty unusual. But vented brakes would have prevented it. And, they simply require almost no “fiddling”, which is otherwise common, at least in country that varies a lot in temp.

    Buy a set of Steve’s or a set from Dakota Cub, and don’t look back.

    MTV
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  20. #20
    Steve Pierce's Avatar
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    Quote Originally Posted by mvivion View Post
    My vote is ABSOLUTELY for vented brakes. A Cub Crafters rebuilt SC with their sealed brakes bought me a 709 ride. Temp was -20 or so. Mechanics took plane off floats and installed wheels. Owner taxied plane to (outside) parking. He called mechanic and said left brake is soft.

    Mechanic went out and topped off left brake reservoir.

    All that was unknown to me. I climbed in back to do FR with owner. That plane has a GREAT cabin heater…..the primary outlet of which pointed right at that left brake reservoir.

    We took off, flew a bit, and came to A/P to do landings. Pilot was sharp, straight as a string. As we climbed from first landing, I noticed the left wheel stopped pretty quick after takeoff…..draggy brake.

    Next landing, she went round. That left brake was locked up tight.

    The FAA, bless them, called the mechanic, and said put it in your hangar, we’ll look at it Monday.

    of course, the left brake functioned fine on Monday in a nice warm hangar.

    I put Steve’s brakes in my Cub, and would so so again. I grant you, the above scenario was pretty unusual. But vented brakes would have prevented it. And, they simply require almost no “fiddling”, which is otherwise common, at least in country that varies a lot in temp.

    Buy a set of Steve’s or a set from Dakota Cub, and don’t look back.

    MTV
    Got a call from either the FAA or NTSB on an SQ2 that went over on it's back for the same thing. They thought the pilot was trying to cover his behind.
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  21. #21
    Steve Pierce's Avatar
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    Quote Originally Posted by mam90 View Post
    Steve, I love the pictures of your Cub vs your customers airplanes! After we rebuilt mine, the first time I went to throw a bunch of muddy, wet fishing gear and fish in the back I hesitated for about one second... Then I smiled and threw it in.....
    I look at it like a truck, the first few scratches hurt the most but it is a tool. I would love to build a nice pretty one for my self one day.
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  22. #22
    Steve Pierce's Avatar
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    Quote Originally Posted by Crash, Jr. View Post
    No offense taken, but I hope you don't take offense if someone questions something that you correct them on. Seems like a lot of folks tend to stay quiet as to not accidentally say something wrong and be corrected on here and that limits discussion. Guess with that I'll leave it to you to talk brakes.
    Maybe try wording your posts a little differently when you are contradicting someone who might know what they are talking about.
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    Steve Pierce

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  23. #23
    mvivion's Avatar
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    Quote Originally Posted by Steve Pierce View Post
    Got a call from either the FAA or NTSB on an SQ2 that went over on it's back for the same thing. They thought the pilot was trying to cover his behind.
    Yep, feds just rolled their eyes in my case. Fortunately, the fed administering the 709 ride was a high time C-46 driver. I learned a couple things from him after he got done apologizing for having to do a 709. It was a good experience after all.

    If you don’t learn something every time you fly, you may not have been paying attention. Sometimes the lessons are more fun than others.

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  24. #24
    Crash, Jr.'s Avatar
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    Quote Originally Posted by Steve Pierce View Post
    Maybe try wording your posts a little differently when you are contradicting someone who might know what they are talking about.
    I'm sorry you got your toes stepped on despite my doing the legwork, calling Dakota as you suggested, and admitting I was wrong.
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    Steve Pierce's Avatar
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    Quote Originally Posted by Crash, Jr. View Post
    I'm sorry you got your toes stepped on despite my doing the legwork, calling Dakota as you suggested, and admitting I was wrong.
    My toes didn't get stepped on, I just wanted the correct information out there. Just for fun, next week or the week after, go back and read all the posts again.
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  26. #26

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    Never actually had to do the ride, but as I understand it there are four tailwheel-qualified 709 check airmen around. I guess they get TDY pay plus a nice hotel. I have prepped two pilots, and met the FAA check pilot in both cases. True gentlemen with a really good attitude. Never heard of a flunked tailwheel 709 ride.

    And yes, closed systems lock up. Usually it means you can't taxi. Ditto parking brakes. Go for Steve's or Dakota.
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  27. #27
    kase's Avatar
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    I just bought a 90hp Super Cub with original 800X4 wheels and brakes. Got a set of North River brake boosters I was gonna give away but thought I might use them to replace the Scott diaphragms. How tough are the expander tubes? Will the booster blow them out asap?

  28. #28
    RaisedByWolves's Avatar
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    Quote Originally Posted by mam90 View Post
    Steve, I love the pictures of your Cub vs your customers airplanes! After we rebuilt mine, the first time I went to throw a bunch of muddy, wet fishing gear and fish in the back I hesitated for about one second... Then I smiled and threw it in.....
    When my cub went on floats I said well it’s just another old supercub now.

    It seems like I have less trouble consistently getting a firm pedal with the Dakota vs Steve’s.
    The Dakota’s usually require you to cut holes in the belly to replace. Dakota and Steve’s are vented. North rivers are nice and simple, unless you fly places where the temperature changes a lot. You’ll either have no brakes or be taxing at love field and have to stop and crack the fill plug as it takes almost full power to taxi. I like the pedal having no play, and love my Dakotas. The extended top works well for 500x5’s on the anfibs too. They have the same amount of pads as double puck brakes.


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  29. #29
    cubdriver2's Avatar
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    Quote Originally Posted by kase View Post
    I just bought a 90hp Super Cub with original 800X4 wheels and brakes. Got a set of North River brake boosters I was gonna give away but thought I might use them to replace the Scott diaphragms. How tough are the expander tubes? Will the booster blow them out asap?
    The stock expander masters and brakes will lock a 31 up to 2300rpm with a 90/0200

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  30. #30
    Steve Pierce's Avatar
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    Quote Originally Posted by kase View Post
    I just bought a 90hp Super Cub with original 800X4 wheels and brakes. Got a set of North River brake boosters I was gonna give away but thought I might use them to replace the Scott diaphragms. How tough are the expander tubes? Will the booster blow them out asap?
    From the STC:
    Any
    wheel/brake assembly installed on an airplane equipped with the brake booster must have a brake FAA
    approved for a maximum available hydraulic pressure of at least 1698 PSI as defined by the brake’s
    original certification basis (TSO-c26, TSO-C26a, TSO-C26b, or TSO-C26c; or the airplane’s certification
    basis if the brakes were approved as part of the airplane type design).
    Steve Pierce

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    But more practically - the stock brakes could easily lock up. Why on earth would you want to apply more pressure than that? If you just apply needed force, even a huge power brake cylinder should not affect the expander tube.

    That said, the original diaphragms worked exceedingly well, and with the proper screws and tools I could change a diaphragm in ten minutes, including seat lacing. Save the boosters for disc brakes. Opinion.

  32. #32
    kase's Avatar
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    I pumped up the brakes and not impressed. My first 2000 hours of cub time was in a PA11 and don’t remember the brakes being so crappy. Maybe just spoiled with Clevelands and brake boosters.

  33. #33
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    Quote Originally Posted by kase View Post
    I just bought a 90hp Super Cub with original 800X4 wheels and brakes. Got a set of North River brake boosters I was gonna give away but thought I might use them to replace the Scott diaphragms. How tough are the expander tubes? Will the booster blow them out asap?
    The original expander tubes require a certain volume of fluid to expand enough to apply the brakes. The original master produces that volume. This is done at a maximum pressure of 350 psi.

    The booster masters put out a small volume at a much higher pressure. They are intended to be used with brake cylinders which move very little so in turn require a small volume of fluid. Since they are small they require more pressure to exert their clamping force.

    The issue arises when you install a large diameter tire on the original brakes. The large diameter has more mechanical advantage working against the brakes. Thus the brakes need to be able to apply more resistance force to the wheel rotation. The original brakes have difficulty doing this. Thus people started using disk wheel brakes with the original masters. While it was an improvement, the original masters couldn't put out the amount of pressure which the disks required to function to their best ability.

    The master cylinders need to be matched to the wheel cylinders taking into consideration the tire diameter. Low volume = high pressure. Higher volume = low pressure.

    Kase, does your 90 Cub have parking brake valves? If so, You can set the parking brake, add a few drops of fluid and release the parking brake valve. This will give you a harder pedal.

    The North Rivers were designed to be an inexpensive solution to the issue. Yes they are susceptible to temperature changes due to them being a closed system. This can be a nuisance. A simple fix is an added reservoir as I've shown in post #6. Years after the North Rivers were on the market other people designed vented systems which solved this issue. Since they were more complicated to manufacture they are more expensive. All of the replacement masters are designed to put out higher pressures with lower volumes to operate on high pressure disk brakes.

    The original diaphragm can fail suddenly giving no brake due to it's design. All of the others are less likely to have a sudden total failure since they are pistons with "O" rings.
    N1PA
    Thanks Steve Pierce thanked for this post

  34. #34

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    Feb 2016
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    I have a stock 150hp model and only recently noticed it has the parking brake valves. However, the levers from both are missing. Are these available to buy or would anyone have them lying about spare?

    Thanks.

  35. #35
    Steve Pierce's Avatar
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    I would contact Univair as a possible source to purchase since they make new parking brake valves. Maybe they will sell you just the arms.
    Steve Pierce

    Everybody is ignorant, only on different subjects.
    Will Rogers
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  36. #36

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    Might ask yourself why the levers are missing. We have a Super Cub with valves safety wired open. We did not do that arbitrarily; there was a reason.

  37. #37

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    Quote Originally Posted by bob turner View Post
    Might ask yourself why the levers are missing. We have a Super Cub with valves safety wired open. We did not do that arbitrarily; there was a reason.
    There is a safety issue with the park park valves that CubCrafters uses on EX and FX models. They completely isolate the brake master cylinder from the wheel slave cylinder. Start the engine with the parking brakes set and, if there is insufficient trapped pressure, the airplane will start moving. No pressure on the brake pedals will help as they are isolated from the brakes.

    The Scott parking brake valves I have flown with on several different airplanes (including to the best of my recollection the PA-18 ) release as soon as pedal pressure exceeds the trapped pressure. No safety issue that I know of. I suppose if you worked hard at it you could set the parking brakes in flight.
    Likes DENNY, gdafoe liked this post

  38. #38

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    It has happened way too many times around here - once resulting in minor damage. The Super Cub is in a flying club, and while the pilot group with access is carefully selected, the brakes got partially locked on a seriously regular basis.

    I would have removed them completely.

    Old timers in San Diego and Grants Pass will remember Don Marks. He was a mechanic’s mechanic, and my mentor. The two of us converted a Stinson to dual brakes in an afternoon! He hated lightplane parking brakes! It was long after he escaped to Oregon that I discovered why.

  39. #39

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    Feb 2015
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    I have Steve's boosters on my Cub, once you figure out how to bleed them it couldn't be easier.
    I can go years without having to add any 5606 to the system.

  40. #40

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    Jul 2017
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    I recently installed the Dakota red top master cylinders and linkage, we bled the system as directed and have a pretty solid pedal when brakes are applied. The problem I am having is the amount of travel the brake pedal travels before the brakes reach a firm pedal, we adjusted the Dakota linkage as directed. I flew the North River system for 40 years and got used to having little or no travel in the brake pedals when brakes were applied. Do vented systems like Steve's and Dakotas require extra pedal travel or can they be adjusted. I noticed a set screw on the master cylinder that could be used to move the master cylinder arm forward, or can the linkage be shortened to move the master cylinder arm forward without effecting the braking action? I have the linkage adjusted to allow the master cylinder arm approximately 1/16" inch of play, I even put new pads on to try to shorten the travel!
    The workmanship and customer service are great from the Dakota office in South Dakota, no complaints there.

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