1964 wheel brake cylinders

[Jack J.]

I WAS warned/advised by Ed Johnson. All 4 wheel/tire backsides show evidence of silicone brake fluid. These wheel cylinders were from Rockauto, ACDELCO -Professional (MADE IN CHINA). One step forward- two steps back. I have my work cut out for me. Jack J.

[Edward J.]

Re: 1964 wheel brake cylinders

Jack, when you go through the brake system , anything that has rubber components maybe be damaged also, such and rubber hoses, master cylinder internal rubber cups. make sure the system is flushed or the dot 5. Good luck.

[Jim L.]

Re: 1964 wheel brake cylinders

I WAS warned/advised by Ed Johnson. All 4 wheel/tire backsides show evidence of silicone brake fluid. These wheel cylinders were from Rockauto, ACDELCO -Professional (MADE IN CHINA). One step forward- two steps back. I have my work cut out for me. Jack J.

Well, that's a Real Good Thing.

What are you trying to say? Are you seeing brake fluid leaks? If so, it's not the fault of the DOT5 fluid.

[Jack J.]

[Richard M.]

Re: 1964 wheel brake cylinders

I'm thinking those seals are such poor quality that DOT 3 or DOT 4 or DOT 5.1 would leak also.

Rubber products from there have and will continue to be inferior and problematic.

If mine, I'd find some NORS USA cylinder seals and replace all 8 and rebleed with the DOT 5.

I know this is a controversial subject, but DOT 5 has been a blessing for every car I've restored years past. This new rubber is junk and will continue to be our nemesis.

Rich
PS Also, don't discount the possibility that those wheel cylinder castings are defective. I had a reproduction chinese manufactured 1961 water pump fail after a very short amount of time, cause by porosity in the casting. Reference thread HERE.

[Larry M.]

Re: 1964 wheel brake cylinders

Jack needs seals made of EPDM rubber (preferred Parker or other major USA mfg). They are proven to work and seal with all brake fluids..........especially DOT 5. SBR rubber seals are iffy for DOT 5........they may or may not seal depending on the DOT 5 fluid used. Some brake fluids differ in minor properties, but this can be significant in some cases.

I think many brake seals are still made with SBR.

All this is explained in detail in the Parker O-Ring Handbook...........which has been an industry STANDARD for decades. I also have in my library a couple of older US Military Testing Documents regarding the use of various brake fluids and seal rubber compounds. They confirm what I have stated.

Larry

[Jack J.]

Re: 1964 wheel brake cylinders

Richard & Larry, last Thursday I ordered new seals with the idea of switching to Dot 4 brake fluid. Both of you, now have me thinking about the EPDM rubber seals (Parker) or ? Who is my best bet for purchasing the suggested seals and how would I know if the seals composition is compatible with Dot 4? Part numbers would obviously be beneficial. Thanks, Jack J.

[Larry M.]

Re: 1964 wheel brake cylinders

Jack:

According to Parker Handbook and Military Test Documents, EPDM is good for DOT 3 or DOT 4 or DOT 5. Parker has a special blend number as well (EPDM #E0667-70), but in general just EPDM will be fine for all.

SBR rubber is also used for brake seals. It is good for DOT 3 or DOT 4 and perhaps DOT 5, depending on the DOT 5 fluid exact composition. Some will work with SBR and some will not. This was shown in the military testing documents.

I do not know who supplies seals with what rubber. I think many still used SBR.......probably made overseas as well..........so it will be fine for DOT 3 or DOT 4. But likely it will not be okay for many DOT 5 fluids. So it is your task to find out who sells what and then buy what you need. Not what you wanted to hear, I know.

Just about anybody's seals will be okay with DOT 3 or DOT 4. But if you want to stick to DOT 5, you need to find a supplier that sells EPDM rubber seals. You can call Wagner, EIS, Raybestos and others to see what it is that they sell/supply. I have no part numbers to help you. A quick check on-line shows that Dorman sells EPDM wheel cylinder seals.

Twenty-five years ago, I purchased stainless steel sleeved calipers from DR VETTE (now CSSB, Inc). I used DOT 5 from Stainless Steel Brake Company (company that first began sleeving our Corvette brakes back in the 1970's). I have never had a leak in the twenty-five years, so I didn't need to buy parts.......so I haven't looked for any. I still have DOT 5 fluid for refills.

Sorry I cannot be more help. I do know that if you search on-line for brake rubber parts that are EPDM, a lot of leads come up. Hopefully you will be successful. Otherwise, just buy from any major brake parts company and use DOT 3 or DOT 4 and be happy.

It is a "brave new world" that we now find ourselves in. .

Larry

[Jack J.]

Re: 1964 wheel brake cylinders

Larry, THANK YOU! for your much appreciated response. Jack J.