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1st Generation 1964 1/2 - 1973 - Questions & general discussions that apply to a specific year => 1966 Mustang => Topic started by: 69cobrajetrugae2 on February 17, 2017, 04:31:03 AM

Title: Opinion on the Master Cylinder
Post by: 69cobrajetrugae2 on February 17, 2017, 04:31:03 AM
Here is my master cylinder from a June 1966 San Jose birthed, 1966 C code convertible with a T-10, stereophonic AM stereo, and 15K original miles.

I have never checked the brake fluid level because the cap was stuck and we Don't drive it much.  The master finally quit and I would like to know if it looks like the Master Cylinder is factory installed. Thanks!
Title: Re: Opinion on the Master Cylinder
Post by: ChrisV289 on February 17, 2017, 07:23:02 AM
Are there any numbers on the left hand side when looking at it while installed?
Title: Re: Opinion on the Master Cylinder
Post by: 69cobrajetrugae2 on February 17, 2017, 11:30:04 AM
I don't see any.
Title: Re: Opinion on the Master Cylinder
Post by: J_Speegle on February 17, 2017, 07:29:52 PM
IMHO Cap, stamping and master cylinder appear to be consistent with others of that period and plant

Date coding is a little difficult to figure out
Title: Re: Opinion on the Master Cylinder
Post by: 69cobrajetrugae2 on February 18, 2017, 12:31:34 PM
I located an expert in sleeving master cylinders, 40 years in the brake business, and initially he thought that the 15.000 mile 1966 mustang story of mine was made up crap which is a common opinion of car guys.

He said that it must have been changed, to him it was just another old Bendix master cylinder.

I agreed that I don't know for sure if the master was ever changed or removed from the car and proceeded to tell him the reasons for my opinion.

I cleaned and borescoped the mounting hardware.  The hydraulic nut had no scars, in particular any that would be created in a counterclockwise direction.  The dum dum putty had encroached around the mounting flange and the patina around the area looked uniform and the 2 mounting nuts we're snug but not but knuckle buster tight and again, no scars evident.  The clip on the brake pedal was pristine and the rust on the pedal rod was uniform and the stop light switch looks undisturbed as well.

He brought out a few master cylinders with the same part number as mine, it's possible that he wanted to sell me one as opposed to sleeveing mine.

One had less machining around the mounting flange and a 129 date code.  I told him it was December 59, no other combination makes sense, which means mine is June or August 1962.

He still wasn't convinced.  He was looking at the inboard seal, " this longhand script on the Bendix logo hasn't been used since the early sixties" he said. He was looking real close at the stainless steel reed valves on the piston assembly so I know he hasn't seen one of those in a long time, if ever.

So there we have it. Reason number 56 the car has 15K. Hope this offers some insight into date coding Bendix master cylinders of this type.  I am going back next week to pick it up, if any of you need me to eyeball a master he has in stock, and he has plenty, or get some other information, PM me, thanks.
Title: Re: Opinion on the Master Cylinder
Post by: Anghelrestorations on February 18, 2017, 02:17:03 PM

The date codes on all the master cylinders (Bendix) are a Julian date code.  From 001 to 365.  There is no year just the days.  Assuming this is a Bendix unit or the others you mention it would be the same. 
Title: Re: Opinion on the Master Cylinder
Post by: 69cobrajetrugae2 on February 18, 2017, 05:24:18 PM
You are likely correct Marcus, but there is some confusion out there on Bendix and the date codes.  Some guys say that the year is in the casting number, who knows.

Engine blocks and other parts are time/day/year stamped, why would masters not be required to have the same documentation?

They might be "year" stamped with the font or machining since I noticed that on the ones I looked at had different fonts and we're machined differently.  The raw casting looked identical.

A 96 year old retired bendix employee might say, "Oh, that's a 64", or that's a 72 by appearance alone.

Generally speaking from a company liability standpoint, the less information placed on any product the better.
Title: Re: Opinion on the Master Cylinder
Post by: ChrisV289 on February 18, 2017, 07:22:40 PM
I always thought this was the date code on the side. Unless in 66 they changed.
Title: Re: Opinion on the Master Cylinder
Post by: Bob Gaines on February 18, 2017, 11:29:00 PM
The date codes on all the master cylinders (Bendix) are a Julian date code.  From 001 to 365.  There is no year just the days.  Assuming this is a Bendix unit or the others you mention it would be the same.
I have to agree with Marcus. At least as far as 65-70 disc brake master cylinders are concerned which is my filed of interest. On those disc brake master that I have studied my confidence level is high that those are typically Julian day of the year date code and not a year date code. I am not sure if the manual brake masters are marked the same way .  I would be surprised if they were not . That is if they are Bendix marked units any way. 
Title: Re: Opinion on the Master Cylinder
Post by: 69cobrajetrugae2 on February 19, 2017, 06:47:02 AM
That looks like a date code on the master that Chris has.  Why did they make a single pot anyway?  To save 15 cents a car? Of course that's the reason why they provided it to their customers.

Remember, if a accident happens as a result of a master cylinder related brake system failure, the auto company and/or the parts vendors are going to blame the motorist and/or mechanic or repair shop.  The repair shop will deny responsibility along with the others since they don't know for sure who's hands we're in there.

The attorney for the plaintiffs, which would be the motorist and/or his surviving family, would have to prove it.

If the parts we're dated and tracked then he could get information on other parts, where they went into what cars and so forth.  If he finds that 59 master cylinders made between may 5 1965 and may 30 1965 failed and 15 accidents happened as a result, including his clients, then if I, or any of you we're jurors we might find for the plaintiffs.

This is likely the reason for the inconsistent or missing date coding on master cylinders.  The poor widow lost her case and is broke and crying with 8 kids and has nightmares of her husband screaming, "there's no brakes"!!

The fat cats are smiling as they stuff their faces at a high end steakhouse to celebrate their victory.

Where are the government regulations on brake parts?  Oh right, they are too busy figuring out how to screw over the public on smog equipment.

The ability to stop a car is the most important safety item in a car, number 2 is tires, number 3 is seat belts.  There have always been tire standards and tracking, funny that brakes we're overlooked. I forgot fly by wire throttles as in the case of a Japan car company.  Initially they said it was the customers floor mat bunching up to the throttle pedal and recalled cars to secure the mats.  Nice.  Take a look at the hole in a San Diego hillside where a CHP officer was unable to stop his Japan car, he, his wife, his 12 year old daughter and his brother in law passed away in sheer terror and the japan company quietly settled on a gag order and continued to kill people in their cars.

 How many families have been burned alive by a brake pedal that went to the floor and the evidence is gone because it was never there in the first place?

The attorneys can't take the case because any evidence that he would need to prove what happened is not available and he would surely lose. How many court cases involving faulty brakes and the resulting liability have there been in the last 75 years?

Tractor trailers still use asbestos, the best brake material is also the cheapest and the powerful corporations like that.

Don't believe me?  Next time you drive down a grade follow one, burning asbestos smell is unmistakable as most of you "seasoned" gentleman know.

Title: Re: Opinion on the Master Cylinder
Post by: Anghelrestorations on February 19, 2017, 12:02:38 PM

This is one of those articles I never finished, but did alot of research on.  Alot of my information comes from the Mopar world where Bendix was also the supplier.  The casting date on the bottom is a Julian date, however they started adding manufacturing information and the assembly date on the side of the master cylinder.  This is something you start seeing especially around 1969 and 1970.  For both drum and disc brake master cylinders. 

Another thing you can do on the early original master cylinders we are talking about here is look at several.  There should not be anything beyond the date code range of 001 to 365 cast on the bottom. 
Title: Re: Opinion on the Master Cylinder
Post by: 69cobrajetrugae2 on February 19, 2017, 06:45:02 PM
The numbers on the side of ChrisV master, IF it's a date code, would be November 6 1965 or November 5 1966, either date code would likely be too late for a 1965 mustang.  I can't tell if the number is cast or stamped.

Good idea Marcus, I'll take pictures of as many as I can next week.  This shop has a 40 year stash of undisturbed brake parts and many boosters.  What is a rare booster or master part number for a 69/70 mustang?
Title: Re: Opinion on the Master Cylinder
Post by: Anghelrestorations on February 19, 2017, 11:04:18 PM

The rare master cylinder is the one you cant find... :)
I will let others comment on what they think is rare.