Convince me of the right thing to do - brake hose replacement

[Mark89114]

Finally decided to replace the leaking caliper, after last year annuals brake bleeding a bunch of black film came out of the system, my mechanic thinks it is something in the hoses degrading and seems reasonable to me.  Decided to ignore it last year but now the caliper is too far corroded so I decided to fix it all……which is where the complications start.  The hoses connected to the foot brake cylinders are buried deep under the outside panels requiring a lot more panel removal and disassembly than I planned.  Now I am doubting my decision to do all this, which at this point isn’t much.  The hoses that are inaccessible are covered in steel braid, the easy to replace ones are just regular black hose brake lines.  They are rubber hoses, not Teflon based on part numbers.  
 

The clear hose leading from the reservoir has a collection of sediment in the bottom of it so something has clearly degraded and something needs to be done.  I would hate to go to all the effort to purge the lines to only have the problem resurface again.  My brakes have never been impressive in my opinion so this probably needs to be done, but I am just dreading it.  
 

What thinks everybody?
 

 

[T. Peterson]

6 minutes ago, Mark89114 said:

Finally decided to replace the leaking caliper, after last year annuals brake bleeding a bunch of black film came out of the system, my mechanic thinks it is something in the hoses degrading and seems reasonable to me.  Decided to ignore it last year but now the caliper is too far corroded so I decided to fix it all……which is where the complications start.  The hoses connected to the foot brake cylinders are buried deep under the outside panels requiring a lot more panel removal and disassembly than I planned.  Now I am doubting my decision to do all this, which at this point isn’t much.  The hoses that are inaccessible are covered in steel braid, the easy to replace ones are just regular black hose brake lines.  They are rubber hoses, not Teflon based on part numbers.  
 

The clear hose leading from the reservoir has a collection of sediment in the bottom of it so something has clearly degraded and something needs to be done.  I would hate to go to all the effort to purge the lines to only have the problem resurface again.  My brakes have never been impressive in my opinion so this probably needs to be done, but I am just dreading it.  
 

What thinks everybody?
 

 

Most everyone on this forum has more mechanical skills than do I, but I can still operate a phone: “Mr. airplane mechanic, when can I bring you my plane….

[RobertGary1]

You’re talking about the steal pipes? Never heard of replacing those. Usually it’s the rubber hoses under the wheel well. Trivial to replace if you’re already bleeding 

[1980Mooney]

1 hour ago, Mark89114 said:

Finally decided to replace the leaking caliper, after last year annuals brake bleeding a bunch of black film came out of the system, my mechanic thinks it is something in the hoses degrading and seems reasonable to me.  Decided to ignore it last year but now the caliper is too far corroded so I decided to fix it all……which is where the complications start.  The hoses connected to the foot brake cylinders are buried deep under the outside panels requiring a lot more panel removal and disassembly than I planned.  Now I am doubting my decision to do all this, which at this point isn’t much.  The hoses that are inaccessible are covered in steel braid, the easy to replace ones are just regular black hose brake lines.  They are rubber hoses, not Teflon based on part numbers.  

The clear hose leading from the reservoir has a collection of sediment in the bottom of it so something has clearly degraded and something needs to be done.  I would hate to go to all the effort to purge the lines to only have the problem resurface again.  My brakes have never been impressive in my opinion so this probably needs to be done, but I am just dreading it.  

Clear hose? I am confused - all I have ever seen are steel brake lines.  The only flexible hose goes to the main landing gear calipers and yes those need replacement sometimes - many last 40+ years. 

As for the steel brake lines and reservoir - if you have contamination and/or sediment then those need to be flushed.

 

 

[carusoam]

How old is the system?

Got any pics of the black film?

What brake fluid do you have in there?

The older brake fluid / aka Cherry juice… would get old and gel up… while turning a darker red…

 

PP thoughts only, not a mechanic…

Best regards,

-a-

[EricJ]

It sounds like you're on your way to a complete flush and refill, in which case I'd echo that it's an opportunity to put synthetic fluid in and get rid of the gooey old 5606.

These are the two synthetics used:

Royco 782
https://www.aircraftspruce.com/catalog/lgpages/anderolr782hf.php

Aeroshell 31

https://www.aircraftspruce.com/catalog/pnpages/08-14635-1.php

[Mark89114]

To clarify, what I think in my head does not get translated to words or speech for that matter.

2000 ovation all flexible hoses are dated 2000.

There is a clear hose that goes from the reservoir in tail access forward to a T fitting under pilots feet.  That has some layer of sediment in it.

I am not replacing the steel hoses.

There are flexible hoses that run to the calipers in the respective wheel well, and way underneath the front panels near the firewall where all of these additional flexible hoses are located, the hard to get ones are steel wrapped.  These are the ones I need motivation to do the right thing on and replace.  They are 22 years old.  I am thinking do this now and I am good for another 22 years......

Unfortunately no pictures of the black film.  when we were bleeding the brakes with the pot from the calipers this fluid was being ejected, the theory is something in the hoses degrading which leads to this whole question.

Someone mentioned mechanic, my preferred mechanic who I discuss this with has zero time, my secondary mechanic while OK is not a huge fan of doing extra work and this is a lot of extra work, he is also busy.  I am more than capable of doing it, just time budgeting.

And yes will be replacing the old fluid with synthetic, which isn't gooey just has that garbage in it.

[gmonnig]

My last annual I did a complete overhaul of the brake system which was quite the headache. Since my flaps are hydraulic and connect to the brakes, it was double the fun. It was an opportunity to change out all the seals and get some shiny new braided lines. If I had to guess, it was probably around 2AMUs  of my $5500 annual. Definitely glad it was done but the multiple A&Ps working on it said it's wasn't the most fun. 

[LANCECASPER]

8 hours ago, Mark89114 said:

To clarify, what I think in my head does not get translated to words or speech for that matter.

2000 ovation all flexible hoses are dated 2000.

There is a clear hose that goes from the reservoir in tail access forward to a T fitting under pilots feet.  That has some layer of sediment in it.

I am not replacing the steel hoses.

There are flexible hoses that run to the calipers in the respective wheel well, and way underneath the front panels near the firewall where all of these additional flexible hoses are located, the hard to get ones are steel wrapped.  These are the ones I need motivation to do the right thing on and replace.  They are 22 years old.  I am thinking do this now and I am good for another 22 years......

Unfortunately no pictures of the black film.  when we were bleeding the brakes with the pot from the calipers this fluid was being ejected, the theory is something in the hoses degrading which leads to this whole question.

Someone mentioned mechanic, my preferred mechanic who I discuss this with has zero time, my secondary mechanic while OK is not a huge fan of doing extra work and this is a lot of extra work, he is also busy.  I am more than capable of doing it, just time budgeting.

And yes will be replacing the old fluid with synthetic, which isn't gooey just has that garbage in it.

Get someone to do this that has years of experience bleeding Mooney brake systems. People have posts on Mooneyspace of frustration trying to get all of the air out of the system. The likelihood of a person getting it right the first time of ever doing is not good.

[Guest]

20 hours ago, Mark89114 said:

Finally decided to replace the leaking caliper, after last year annuals brake bleeding a bunch of black film came out of the system, my mechanic thinks it is something in the hoses degrading and seems reasonable to me.  Decided to ignore it last year but now the caliper is too far corroded so I decided to fix it all……which is where the complications start.  The hoses connected to the foot brake cylinders are buried deep under the outside panels requiring a lot more panel removal and disassembly than I planned.  Now I am doubting my decision to do all this, which at this point isn’t much.  The hoses that are inaccessible are covered in steel braid, the easy to replace ones are just regular black hose brake lines.  They are rubber hoses, not Teflon based on part numbers.  
 

The clear hose leading from the reservoir has a collection of sediment in the bottom of it so something has clearly degraded and something needs to be done.  I would hate to go to all the effort to purge the lines to only have the problem resurface again.  My brakes have never been impressive in my opinion so this probably needs to be done, but I am just dreading it.  
 

What thinks everybody?
 

 

I think it’s a waste of time and money to replace everything.  I’d be surprised if a caliper is corroded so badly on a 2000 model, but who knows.  Buy a pressure pot, fill it with clean hydraulic oil of either type, connect it to the top of the reservoir in the avionics bay, pump it up to 10-15 psi and open the bleeder screws at the wheels one at a time to purge out the old stiff fluid. A few quarts of hydraulic oil is cheap.

[Mark89114]

Here is the garbage in the clear line....no idea where it came from.  This is length of clear line from reservoir to the front.  Something somewhere has come apart.  

Also attached is picture of the corrosion in the caliper.  Replaced o rings twice since I have had airplane.  First time lasted abiut 4 years before leaking, last time about 9 months. 

[Guest]

22 hours ago, Mark89114 said:

Here is the garbage in the clear line....no idea where it came from.  This is length of clear line from reservoir to the front.  Something somewhere has come apart.  

Also attached is picture of the corrosion in the caliper.  Replaced o rings twice since I have had airplane.  First time lasted abiut 4 years before leaking, last time about 9 months. 

I’d polish the piston bores with some 400 wet and dry paper, then dunk it in Alodine.  Open the plastic line at the front near the mater cylinders and flush/drain the line to that point, and if it won’t come clean replace the line, it’s almost as cheap as the fluid you’ll need to flush it.

[PT20J]

My fluid was replaced by the previous owner about 6 years ago. I think the heat from the brakes is what causes the 5606 fluid to deteriorate. Every year I open the bleeders and let about half a cup drain out of each topping off the reservoir between draining each caliper and after I'm done and it seems to keep the fluid from thickening.

[Mcstealth]

Do not discount the possibility that the sediment may be coming from the caliper. 

[M20F]

I fly a Mooney for speed.  I had my brakes removed to lessen the weight and give me more speed.  

[Pinecone]

13 hours ago, M20F said:

I fly a Mooney for speed.  I had my brakes removed to lessen the weight and give me more speed.  

That works very well.  Until the speed carries to the end of the runway.