Topic: 66 Dearborn - master cylinder and cover

[teamroper60]

I own a 66 C-code, 3spd car, built in Dearborn on Dec. 20, 1965.  My Dad bought this car new on Jan. 8, 1966.  I got the car from him in 1989.   This car has manual drum brakes.  Until last week, when I rebuilt it as part of a complete redo of the brake system, the master cylinder had never been off the car and other than adding fluid, hadn't been touched in any way (verified with my Dad).   It is natural color with a zinc dichromate screw on cap and that is the way it was when Dad bought the car (again, verified).  It also has the brass adapter mentioned by Bob Gaines in the post above.  The only paint on the master cylinder when I took it off the car to rebuild, was some green paint (kind of a seafoam green) on the square headed plug just above where the brake proportioning valve (the looped line from the MC to the brass distribution block) attaches to it.

I can take a picture and post it if anyone wants to see it but as I said, I recently rebuilt it and cleaned that plug, so it doesn't have much of that green paint on it anymore, so I am not sure if that would help anyone or not.

[CharlesTurner]

I own a 66 C-code, 3spd car, built in Dearborn on Dec. 20, 1965.  My Dad bought this car new on Jan. 8, 1966.  I got the car from him in 1989.   This car has manual drum brakes.  Until last week, when I rebuilt it as part of a complete redo of the brake system, the master cylinder had never been off the car and other than adding fluid, hadn't been touched in any way (verified with my Dad).   It is natural color with a zinc dichromate screw on cap and that is the way it was when Dad bought the car (again, verified).  It also has the brass adapter mentioned by Bob Gaines in the post above.  The only paint on the master cylinder when I took it off the car to rebuild, was some green paint (kind of a seafoam green) on the square headed plug just above where the brake proportioning valve (the looped line from the MC to the brass distribution block) attaches to it.

I can take a picture and post it if anyone wants to see it but as I said, I recently rebuilt it and cleaned that plug, so it doesn't have much of that green paint on it anymore, so I am not sure if that would help anyone or not.

Master cylinders were usually supplied by Bendix.  If you flip it over and look at the bottom, there is usually a date code and the 'B' Bendix logo cast in.  Was there strip caulking around where the master cylinder goes into the car?  Any sealant over-spray around the bolts from when the firewall was sprayed?  A few pics would probably help. 

[mikelj5S230]

I am assuming the black paint on the cap would show some scratches when the wire bails were put in place.

[carlite65]

I am assuming the black paint on the cap would show some scratches when the wire bails were put in place.

uh, no, not on a '66.

[Richard P.]

Their was a excellent article published in Month Monthly sometime ago by Marcus Anghel about the use of the sticker/decal on 1967 Mustang master cylinder caps. The part # on the 1967 sticker is the same as used on the 1966 Disc Brake M/C Cap. If I recall correctly the decal was used to show a change in the use of a different brake fluid because of the disc brake temperatures. This make a lot of sense and I'll go with the written Ford documentation until something else is provided.

[J_Speegle]

We seem to be going in different directions. The latest post (to a 6 year old thread) was concerning  a 66 non-disc brake cylinder. So no bale and no decals

[teamroper60]

Master cylinders were usually supplied by Bendix.  If you flip it over and look at the bottom, there is usually a date code and the 'B' Bendix logo cast in.  Was there strip caulking around where the master cylinder goes into the car?  Any sealant over-spray around the bolts from when the firewall was sprayed?  A few pics would probably help.

There was some "gunk" around it and on the bolts when I took it off.   I cleaned the dirt and gunk that had built up from 49 years of use off of it and the bolts when I had it off the car.  I have been doing a lot of work on this car lately and trying to always put it back like it was and should be as I go.   If there had been any indications of paint on it when I took it off, I would have painted it (which would have covered that green paint, which I didnt attempt to replicate), but there wasn't and after checking with my Dad, there never was, so I didn't.   The only pic I have of it is after it was re-installed, which is why I said I am not sure it is of benefit to anyone..   Is there a way to upload a pic from my computer to this thread?

[carlite65]

you can upload by hitting 'reply' then use the 'attachments and other options' just below the reply box. very easy to do on this site.

[CharlesTurner]

When you reply to a post, there's an 'Attachments and other options' below.  Use this to attach pictures from your system.

Was there any strip caulking at the back of the master cylinder?  This is almost always there on original master cylinders, but gets left off when new units are installed.

Also, the 'gunk' on the bolts is good, but I was mainly questioning if the same gunk was on the master cylinder?

I'm sure we can probably come up with some reference pics.  Attached is one, 22k original mile car, Dearborn built.  I don't have a scheduled build date.  The black paint on the cap is still evident and also note the absence of a fitted plug on the top.

[Bob Gaines]

Their was a excellent article published in Month Monthly sometime ago by Marcus Anghel about the use of the sticker/decal on 1967 Mustang master cylinder caps. The part # on the 1967 sticker is the same as used on the 1966 Disc Brake M/C Cap. If I recall correctly the decal was used to show a change in the use of a different brake fluid because of the disc brake temperatures. This make a lot of sense and I'll go with the written Ford documentation until something else is provided.

2 different stickers used in 67 one has the 66 engineering number the later did not.

[teamroper60]

When you reply to a post, there's an 'Attachments and other options' below.  Use this to attach pictures from your system.

Was there any strip caulking at the back of the master cylinder?  This is almost always there on original master cylinders, but gets left off when new units are installed.

Also, the 'gunk' on the bolts is good, but I was mainly questioning if the same gunk was on the master cylinder?

I'm sure we can probably come up with some reference pics.  Attached is one, 22k original mile car, Dearborn built.  I don't have a scheduled build date.  The black paint on the cap is still evident and also note the absence of a fitted plug on the top.

Yes, that is the "gunk" that was on mine  There was some semi-hard gunk still on the firewall, perhaps that was the strip caulk?  I don't know.  I left the firewall alone so I could get the MC back in the exact same spot.   I cleaned it off the MC when I rebuilt it. 

However my MC has a square headed plug in that flat area above the proportioning valve.   That's the plug I referenced that had the green paint on it.   Also, my cap is zinc, not silver looking like the one in the pic (which might be just the lighting in the pic).

Thanks for the info on posting a pic.  I tried to upload the pic I have but the computer kept locking up.   It might be because my wife is watching a movie...   I will try it again later.

edit:  one other thing, my MC has a brass fitting between the proportioning valve and the MC.  I notice there isnt one in the pic you posted.  As I have said before, I know with absolute certainty this is the MC that came on the car at delivery, not a replacement.   

2nd edit:  This is not mine but I found a pic of a MC with the plug and fitting like mine has:  http://www.google.com/imgres?imgurl=http://www.allfordmustangs.com/forums/attachments/classic-tech/131338d1306693136-66-master-cylinder-teapot-img_0496.jpg&imgrefurl=http://www.allfordmustangs.com/forums/classic-tech/297571-66-master-cylinder-teapot.html&h=1280&w=960&tbnid=tjd9Xhsujbdc8M:&docid=Gp2ZOd3ZQ5Mc7M&ei=6lH_VaCjJI-zyATKhLvACw&tbm=isch&ved=0CD8QMygYMBhqFQoTCKDAx_3xhsgCFY8ZkgodSsIOuA

From what I can gather, that plug fills the port where there would have been a sending unit for a brake light in some 65's.

[J_Speegle]

NOTE : Going to split the topic from the original thread and move it to the 65-66 section of the site

Some more examples of originals - have allot more that are not in  as nice condition as these though they all have no 64 1/2 switch holes nor need an adapter.













As mentioned - any stamped or cast numbers or letters on the body might help figure things out

[mikelj5S230]

uh, no, not on a '66.

Oh sorry, thought we were talking '67-'68s.

[teamroper60]

NOTE : Going to split the topic from the original thread and move it to the 65-66 section of the site

Some more examples of originals - have allot more that are not in  as nice condition as these though they all have no 64 1/2 switch holes nor need an adapter.


As mentioned - any stamped or cast numbers or letters on the body might help figure things out

Nothing to figure out really.  At least on my end.   I am not looking for information on it or the car.  I already have all of that.   As I said, this car was bought new by my Dad and I got it directly from him.  I was a car crazy kid when he bought it, so I was always with him when he worked on it and once I got to my teens, took over the maintenance on it for him because of his back.  Obviously, I know the history of the car from the day Dad drove it away from the dealership (including what he paid for it) and the repair history as well, right down to the date and mileage of the first oil change and everything else that has been done to it in the 71K miles since it was purchased. 

I only entered into this to try to help when I read something that was posted this month.   I thought it might interest others to know not all MCs were painted.  Perhaps no one cares since it apparently doesnt fit with what is commonly believed to be correct (and may well be correct for most cars, I am only a historian on this particular car).  I dont know. I don't personally care, just trying to contribute.   If that isnt welcome here since I am not a judge, I will leave it alone.  If I am misreading that, please let me know.

[CharlesTurner]

It goes against what is typically seen.  Not saying it is right or wrong, but if you want to help the learning/conversation, then show a picture of the underside of the master cylinder with the markings.

While we would like to believe that you know every single thing ever done to the car, when something goes against the norm, we have the examine all the facts and come to a conclusion.  It's your choice to contribute or not.  There is no rule here that says you have to be a judge to have an opinion.