Topic: 68 Master Cylinder/Lid Finish

[RoyceP]

I found a couple of caps on ebay both listed as C7AZ-2162-A which I'm guessing is a service replacement.  Would this work in my situation as a concours car?

Amazing how different each of the service parts is from the replacements. There are even two different styles of service part, neither resembling the original.

[dkknab]

Per Angel Restorations document attached it lists the C7AZ-2162-A.  Is that not the case?

[Bob Gaines]

I found a couple of caps on ebay both listed as C7AZ-2162-A which I'm guessing is a service replacement.  Would this work in my situation as a concours car?

Jeff's pictures give a advantage on what to look for. If the caps look like the ones in Jeff's pictures then they would pass . If a replacement cap does not look like the assemblyline original then of course it would be subject to possible deductions in concours. Finding a used cap that is in good condition and not rust pitted to refinish is one solution.

[J_Speegle]

Master cylinders can be difficult along with some other parts since they are so often serviced, replaced or rebuilt during the cars earlier owner ship. Add to this the  surface rust often foudn on the main case, exposure to spilled brake fluid and so on.

[RoyceP]

Per Angel Restorations document attached it lists the C7AZ-2162-A.  Is that not the case?

Sure that's the original part number. It's a different part if you look at the photo Marcus provides of the correct assembly line part.


"C7AZ-2162-A Caps would be for master cylinders with two equal size reservoirs so therefore a completely different cap. The cap was stamped with the SAE 70R3 on early cars and SAE J1703 on later cars and had two breather vents on the lip of the cap. Drum brake master cylinder caps never had a mention of Ford specific brake fluid or Ford specifications. This cap was used by all Ford drum brake cars from 1967 to 1973, not just Mustangs."

[Bob Gaines]

Sure that's the original part number. It's a different part if you look at the photo Marcus provides of the correct assembly line part.


"C7AZ-2162-A Caps would be for master cylinders with two equal size reservoirs so therefore a completely different cap. The cap was stamped with the SAE 70R3 on early cars and SAE J1703 on later cars and had two breather vents on the lip of the cap. Drum brake master cylinder caps never had a mention of Ford specific brake fluid or Ford specifications. This cap was used by all Ford drum brake cars from 1967 to 1973, not just Mustangs."

So that there is no confusion to clarify in the context of a 68 "later" doesn't mean later that year but instead later production years had the vents given it was used up to and including 1973. It is a common occurrence that later service parts do not match what came on the assemblyline.

[J_Speegle]

"C7AZ-2162-A Caps would be for master cylinders with two equal size reservoirs so therefore a completely different cap. The cap was stamped with the SAE 70R3 on early cars and SAE J1703 on later cars and had two breather vents on the lip of the cap. Drum brake master cylinder caps never had a mention of Ford specific brake fluid or Ford specifications. This cap was used by all Ford drum brake cars from 1967 to 1973, not just Mustangs."

Believe you will find that the SAE 70RS and SAE J1703 identified the brake fluids to be used since it was a change across all car models and passenger car applications at the same time not just disc or drum applications.  Found plenty of references on the internet about the two and their differences.

[dkknab]

So who manufactured the master cylinder? I'm assuming it wasn't Ford. And what casting numbers or markings can we expect to find on the original proper units? Is there a thread somewhere discussing all this?

[ruppstang]

Bendix was the OEM supplier.

Didn't originals have the round or hex headed screw in the bottom? I looked at some that I have and found two with original type caps and one of them had the hex screw in the bottom.

[J_Speegle]

So who manufactured the master cylinder? I'm assuming it wasn't Ford. And what casting numbers or markings can we expect to find on the original proper units? Is there a thread somewhere discussing all this?

Think we need to specify or maybe split the topic since I think we're getting two or more of the master cylinder comments, findings and details over lapping one anoth. Will look to see if I can separate the two to reduce the possible confusion this may create

+2 On Bendix and your casting information on the bottom of the main body would be different if it was a power disc brake or drum unit along with other details.

Markings are cast into the main body and visible from below the master cylinder the location and how they are arranged differed depending  on when they were made.

Here is a likely 68 example (came out of a reported 68 San Jose car) though its very likely NOT a drum brake application, just to show the details

To the left the Julian date code, the Bendix logo, then the identifying Bendix number

[dkknab]

So here is the bottom of my master cylinder showing casting number of 2227451 and what appears to be a date code of 328

Is the date code decoded as March 2, 1968 or is it a Julian date which would mean it's a November date?

That being said, I think my cap should look like the one pictured here too.

I look to anyone to help confirm this for me. Thank you.

[J_Speegle]

So here is the bottom of my master cylinder showing casting number of 2227451 and what appears to be a date code of 328

Is the date code decoded as March 2, 1968 or is it a Julian date which would mean it's a November date?

As stated believe its a Julian date. We see a change from traditional (or what ever its called) to Julian during 66 production as shown and discussed in another thread and in the article on date coding in the Library

[ruppstang]

So here is the bottom of my master cylinder showing casting number of 2227451 and what appears to be a date code of 328

Is the date code decoded as March 2, 1968 or is it a Julian date which would mean it's a November date?

That being said, I think my cap should look like the one pictured here too.

I look to anyone to help confirm this for me. Thank you.

Do not think it is original because there is no screw in the bottom. Most likely a service replacement.

[dkknab]

Argh... not surprised. So is that casting number not one that could have originally been on the car? It seems to fit the date range. Are there any pictures of the original master cylinder? What are the id numbers for the original one and does that really matter for a concours car? Never ceases to amaze me the things that were changed for a car that had significantly  less than 100k miles on it.  What does that tell you?

[RoyceP]

Argh... not surprised.  Are there any pictures of the original master cylinder? What are the id numbers for the original one and does that really matter for a concours car? Never ceases to amaze me the things that were changed for a car that had significantly  less than 100k miles on it.  What does that tell you?

Brake parts degrade over a period of 10 - 12 years so that is the likely window it was replaced the first time in the past 50+ years. Probably it has been replaced several times by now.