Brake cylinder sleeving

Greetings Glenn, Some folks use brass instead of stainless for sleeving brake cylinders. I would. As far as the rusting is concerned this means (probably) water in the system so how is it getting in? Since you are going through the whole thing anyway have you considered silicone based fluid? I think it's designated DOT4. It was used in postal jeeps. I took one of these apart to do other work and was amazed at the pristine look of the internal brake system parts. Zero corrosion. It may be that this stuff is unsuitable for use in a Corvette, and you would have to bleed the system completely, but you may want to look into it.

J&D Corvette in Bellflower California sells a full conversion that includes stainless calipers. They are definitely a great resource for this sort of project. Get a hold of Woody Park.

Dual master cylinders were in use with drums all 'round a long time before disks were in use.

Mark Rand RTFM

I installed a dual master cylinder on my 1951 Chevrolet 1/2 ton pickup truck with drum brakes front and rear, and it has been working fine for over 7 years. It took a little doing to come up with a cylinder that would work, since the majority of dual master installations seem to be on vehicles with power brakes and I needed something that would work with manual braking. Your rusting problem is probably from moisture that is absorbed by old-style brake fluid. Changing to the newer silicone fluid should eliminate the rust, but as I understand it you will need to completely clean the brake system of all traces of the old fluid first.

Mike

I had some like problems with old Volvos. Water would get in somehow, over time. My solution was to periodically flush the entire brake system with brand new fluid, thus getting rid of all water and dirt that had somehow gotten in.

Joe Gwinn

I hadn't thought of brass. I will look into that. I will be replacing virtually everything but the hardlines and even most of those will be replaced. I have seen stainless brake lines in a refit kit but am a bit leery of stainless brake lines as the fatigue factor could be a problem.. don't know just a baseless fear. As to the water getting in .. sitting in uncontrolled environment for several years tends to do that. It could be that the silicone will be a good cure but I was reading that water still gets into the system .. it just dosen't mix with the silcone based fluid like it does with the glycol based fluids. Thanks for the ideas. Glenn

Mark, any idea what modle/year chevy master cylinder would replace the single on my power brakes? I have done a lot of reading/looking and have not found anything for cars. Glenn

LOL .. that is exactly why I want to go to dual MC .. I recall all to clearly trying to drive down the road and add brake fluid to the resivoir between my feet so I might be able to stop at the next light :) I had a 40 Chev 1/2T and a 57 Chev 1/2T They both had a habit of dropping the pedal to the floor at any whim. I even took the 40 in and had a brake shop go through the whole thing. The only adjusted one end of the slave cylinders and the first time I had to hit the brakes hard the seals blew out. Any ideas on where to look for a dual M/C replacement for 63 power brakes? All the dual M/C vettes are disk drum and I sorta want to stay with the drum drum. Glenn

Replace all the lines too, they are full of rust inside and the rust will hold water and... You'll need an adjustable proportioning valve, the old one will be wrong. Get new flexible lines too. No real need for the sleeves if you replace everything and use DOT 4. Any short-cuts here and you'll be walking, at best!

FWIW,

I had a similar problem with a '66 MGB. I solved the problem by switching to DOT 5 (silicone) brake fluid. A machinist/prototyper/carbuilder told me about this method.

You have to start with a fresh (newly rebuilt and purged system. We rebuilt all the wheel, and Master Cylinders. and purged the rest with ether and blew it all out good. It's been working like a champ for 8 years with @ 7 mo/yr of storage in open barn.

What you are proposing is probably way overkill.

Glycol based fluids absorb water. So any water that enters will eventually be spread throughout the system. Silicone based fluids do not. Silicone based fluid systems may allow water into the master cylinder but I don't see how it would spread. The mail jeep cylinders all around were pristine looking inside. And I know for a fact that this fluid had been in the jeep for at least 12 years. But this is of course only one sample and may be a fluke. Have you heard of stainless tubing developing cracks sooner than plain steel tubing? Something you may not know is that stainless needs free oxygen to keep it corrosion free. The steel develops an oxide coating very quickly when exposed to air. This is what prevents further oxidation. Aluminum also does this. I can imagine a situation where stainless liners would corrode quickly. A couple marine examples: Washington State runs a bunch of ferries. Stainless piping that carries salt water is not used on these boats because of internal corrosion. At least one boat was built and delivered with stainless piping. The boat(s) was (were) returned to the builder to have the SS replaced. In my years working in machine shops near Puget Sound I have made several prop shafts. Most from monel or other high nickel alloys. Some prop shafts that I made were replacements. When this happened the old shaft was always brought in as a sample. The old prop shafts would be put on the stock rack for making odd parts. The stainless shafts always had what looked like worm holes that started at the prop end. These holes would wander down the length of the shaft. The deepest were nearly two feet long. They were caused by the shafts always being submerged in salt water. In the early 1980's it was discovered that the anerobic environment not only allowed the stainless to corrode (expected) but that it also allowed biodegradation of the stainless. This was discovered in the stainless coolant piping in a nuclear power plant. I hope you found the above interesting. ERS

Glenn wrote: I would like to

Joe Way used to post here. you might want to give him a call.

Kevin Gallimore

Isn't silicone fluid DOT5???

What I was told, might not be fact: DOT 5 won't absorb water so it can sit, or, it can boil in racing situations. DOT 4 will keep water suspended and protect the system.

This I believe is what Joe Way, of Sierra Automotive does.

He was a regular on this ng, and I think he still maintains that business. Check him via google.

Jim

LOL it IS a chebby after all :) You have to plan on walking. As it turns out the previous owner made a "repair" to the fuel line when he had the body off and the funky rubber hose he used went gushy inside and plugged up the fuel line sooo. I get to pull the body off and check all the other funky things he did and replace all those nice to get at with the body off things. So yup new brake lines are definately on the list. Glenn

Great link and info. It looks like I wan to go with brass now :) It would have to have a link to the old Gus Wilson stories...I am gonna be wastin a bunch more time now I guess :) Ah well I gotta git into the retired mode so it won't come as such a shock to the system in the next couple of months :) Glenn

Even if you do the conversion, you will still have crap brakes. The fluid is hydroscopic - you need to drain the lines, flush them with alcohol at least every year. (its probably in the service manual for the car.) As your not running the car, you wouldnt have noticed the brakes would not have worked after a hard run when the steam vapour locked the hydraulic lines.

My mechanic measures the water content in the brake lines ever time he services my car - (yeh, slack, its twice a year) - and replaces the fluid if needed. He also measures the ph of the radiator coolant - that goes off too and will corrode out modern mixed metal cooling systems by electrolysis. (The last is most likely not an issue with an old vehicle like yours...)

The days of DYI car servicing for modern vehicles are just about over

- like everything else, technology has moved on and unless you are bloody good, and do it full time, and continually retrain, SOMETHING will get ya.

Andrew VK3BFA.