Okeefe Brakes Locked up

[Dean Westerburg]

I am working on a Sonerai IIL that came with OKEEFE brakes and the pistons are locked up solid. The aircraft sat in a hanger for years. Contacted OKEEFE and they dont have any sort of rebuild kit.

Wondering if anyone else has had issues like this with OKEEFEs and if they were able to repair them?

 

[shocktrooper]

I am working on a Sonerai IIL that came with OKEEFE brakes and the pistons are locked up solid. The aircraft sat in a hanger for years. Contacted OKEEFE and they dont have any sort of rebuild kit.

Wondering if anyone else has had issues like this with OKEEFEs and if they were able to repair them?

My 2L is also equipped with O Keefe calipers. Give this a try....remove the small brake pad (ie very small countersunk brass screws so be careful not to strip the heads), remove the bleed port screws, and gently/slowly fill the caliper with PB Blaster penetrating oil...let sit filled and undisturbed with piston side down for several days and let gravity and the oil dissolve the stuck o ring to piston bore surface of all the dried(stuck) rubber...then use a rubber tipped shop air nozzle on low flow low pressure at the bleed screw port, and the pistons should eventually pop-out. Then you can clean up all bearing surfaces, install a new ,appropriate sized ring and be good to go!

 

[Dean Westerburg]

My 2L is also equipped with O Keefe calipers. Give this a try....remove the small brake pad (ie very small countersunk brass screws so be careful not to strip the heads), remove the bleed port screws, and gently/slowly fill the caliper with PB Blaster penetrating oil...let sit filled and undisturbed with piston side down for several days and let gravity and the oil dissolve the stuck o ring to piston bore surface of all the dried(stuck) rubber...then use a rubber tipped shop air nozzle on low flow low pressure at the bleed screw port, and the pistons should eventually pop-out. Then you can clean up all bearing surfaces, install a new ,appropriate sized ring and be good to go!

I tried something very similar to that but didnt let the PB Blaster sit that long. I'll give it another go with more time. Thanks!

 

[shocktrooper]

I tried something very similar to that but didnt let the PB Blaster sit that long. I'll give it another go with more time. Thanks!

Yes sir...the “patented catapiller action” of PB Blaster is sometimes a slow but very effective process...keeping the parts warm at or near room temps during the entire process will make a measurable ‘time of action’ difference too. A bit of mild direct heat on the caliper just before you try to extract the piston will help as well. Good luck with your repairs.

 

[John B]

Not familiar with that brand of brake but assume they are hydraulic. I have many times taken my grease gun and installed it on the brake line port of the caliper. Pump the gun until the puck comes out. Just did this on some stuck Matco calipers I was given.

 

[tls258]

All great ideas. Could WARM the assembly in small tub or heavy black zip bag in the sun, with the PB on and let cool (even in the freezer) which will draw the fluid in. Repeat as necessary. Acts like a pump. Tapping an inconspicuous but sturdy area will also cause vibration that will help the fluid.

 

[tls258]

O’Keefe spun off from Great Plains. Carries Sonerai landing gear, brakes, wheels, and http://www.okeefeaero.com/about-us.html

 

[Dean Westerburg]

Yes sir...the “patented catapiller action” of PB Blaster is sometimes a slow but very effective process...keeping the parts warm at or near room temps during the entire process will make a measurable ‘time of action’ difference too. A bit of mild direct heat on the caliper just before you try to extract the piston will help as well. Good luck with your repairs.

That worked! I let them sit with penetrating oil (Aero KROIL) for 4 days. When I put the compressed air to the to caliper, the piston shot right out with more force then intended! I guess they just needed more time. Thanks!

 

[Dean Westerburg]

O’Keefe spun off from Great Plains. Carries Sonerai landing gear, brakes, wheels, and http://www.okeefeaero.com/about-us.html

I contacted them before I started taking these apart. The do not offer a rebuild kit or parts. Just new calipers and pads. They also offer the complete kit, rotors and all.

 

[buckaroo]

Are there any particular alternatives to Okeefe brakes? I was looking at black max, but they use ball bearings instead of the stronger tapered bearings in the Azusa wheels that Okeefe sells. Might not hold up to towing.

 

[Dean Westerburg]

I have some Tracy Obriens that are probably going on the Sonerai. I'm not sure if they are available anymore. These OKEEFE's still lock up after the first press and wont release even after cleaning them up and removing all the pitting. There's always Matco if you have a thick wallet.

 

[buckaroo]

My friend, if I had a fat wallet I wouldn't be building a Sonerai

Unfortunately it looks like Obrien doesn't make them anymore. The Okeefe's just don't look too promising.

I may end up getting some motorcycle brakes for 1/4 of the cost. The disc size would be the only problem.

 

[Dean Westerburg]

My friend, if I had a fat wallet I wouldn't be building a Sonerai

LOL!! I hear ya. I have some Matco's on my 701 and they are great, but I wouldnt have spent that kinda money if they didnt come in the kit. I'm interested to see what you work out. My Tracy O'Briens are from 2007, so who knows how well they will still work. Might go back to Cable Brakes if these dont work.

 

[bluerocket]

if you buy good quality equipment you will not have a problem I have a 73 year old warbird the brakes work fine. a new set of brakes for your plane are under $800.00 bucks. I just spent more than that fixing the brakes on my truck. I don't have deep pockets but you have to spend enough to be safe. Or don't fly. You may be able to put on some kart brakes. but that would run over $1000.00 I needed to replace the constant speed prop on my plane. It is a rare Prop and Hartzell really doesn't want to support it any more. They will sell you a new prop for $42,500.00. I was able to find a used one in Texas for $15,000.00 then another $6,500.00 having it rebuilt. It is the cost of flying safe

 

[10kDA]

Just out of curiosity, what kind of brake fluid are you using?

 

[squirrely dan]

I would spend the money and replace. If they lock up or fail it will cost you a lot more than the cost of the brakes. Maybe some medical bills to go with it. The sonerai is about as inexpensive as your going to get. Being cheap or not doing preventive MX is always more expensive in the long and perhaps even the the short run.

 

[[email protected]]

fyi this may help

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[buckaroo]

Thanks for the heads up, Larry. I'm working shipping with the guy now. The design is quite strange. The force of the brake puts enormous load on the outer bearing. It also acts to deform the disc. But it is compact and simple... I am curious how it holds up long term.

Otherwise I was just looking at some small single caliper Nissin brakes.

 

[Dean Westerburg]

Thanks for all your input. I think I am going to buy a new set of OKEEFE brakes and put them on unless I find people saying they are junk and to avoid them. It's the easiest route and they are not that pricy. Does anyone have any thoughts on the quality of new OKEEFE brakes? I am using DOT 4 fluid since the instructions state not to use aviation fluid. Im not sure what was sitting in them for the last 4+ years

 

[John B]

Make sure your master cylinders are suitable for the same fuild too.