67 Shelby master cylinder

There seems to be an NOS one on Ebay right now. Sorry, didn't write down the listing number.

 

The bolt in the bottom is wrong. The assemblyline units should have a wide round allen head. Bob

 

Bob, Can you verify this? Here's why: I just sent out the original M/C from my 67. It is the one I removed in 1971. I had it sleeved and rebuilt. It does not have the fastener you described (thrust head/oval). It is possible the rebuilding kits have the incorrect fastener. This is a possiblity.
But, I bring this up because the M/C I removed has the fastener you described. And, it was a rebuilt bought in 1971 (Bendix brand too).

Then I went and looked in my 1968 Fomoco service manual. (Ok, I'll run into a 1967 manual someday...) and the fastener in the illustraton is clearly a hex bolt style.

 

Rod,the unusual "button top " Allen head cap screw which is used as a stop for the piston inside the M/C is on the assembly line units of not only 1967 Mustangs/Shelby but ALL Bendix M/C used from 67 -69/70 in Shelby, Mustang and Boss. The standard bolt head is used in a lot of later service replacements and rebuilt units I have seen. I have had a few units rebuilt and sometimes the Allen head stop bolt head gets striped and has to be replaced. I have bought many rebuilt units at the auto parts store that still have the button top Allen bolt. Most don't . When the bolts get damaged- which a Allen head would be prone to do if it got a little seized up it was replaced by the rebuilder and or the newer units probably incorporated the different bolt to eliminate the problem before changing the design of the M/C so the stop bolt was not needed at all. All of the new replacement styles that can be bought today don't have ANY stop bolt. I usually have to go through 8 or 10 rebuilt units before I get the one I want. I have someone that rebuilds cores but I have to supply the seal kit (NPD to the rescue). It cost about 3 or 4 times as much to rebuild one rather then to go to the autoparts store and buy one . Unfortunately it is a hassle going through the sorting of correct rebuilds process. I assume the unit bought for your car was a later (1971) service replacement if new and a modified unit if rebuilt. 1971 was plenty of time for those changes to take place. Bob

Here is a picture of one out of a 69 but it is the same Bendix M/C unit. Bob

 

But what of the illustration in the service manual? These are usually printed roughly around the time of vehicle introduction. And well before any rebuilt units are available. What say you?

 

I say this is the way it ended up being used on Mustangs in the field . A lot of illustrations in the service (shop manual) manual are general applications or referred to as "typical" and they look different in appearance then the actual application. The assemblyline manual sometimes also has illustrations that are different then what was actually ended up being used in reality. Just last night I noticed a illustration of the park light light back side metal retainer in the 67 electrical manual. All those that are knowledgeable about 67 and 68 Mustang restorations know that the 67 style is cut out on top and bottom and in 68 it is a solid cone . The illustration in the 67 electrical assembly manual shows the 68 style solid cone . In the assembly drawings in the 67 Shelby assembly manual illustration(Branda reprint) however it shows the correct style cut out in the retainer. Back to the illustration you were referring to on page 2-23 of the 1967 shop manual . First The Shop manual covers more applications then just a Mustang in fact it covers Cougar,Fairlane, Mercury intermediate size cars as well as Mustang. The duel master cylinder at the top of the page is for a drum brake car and the disc brake M/C illustration is obvious to all of those familiar with Mustang disc brake master cylinders as NOT for a Mustang/Shelby by the out of place brake line ports and non Mustang application bleeder valve. It is for a big car application and not a Mustang. It is what as referred to as a "typical " illustration meant to cover a number of applications. Sorry if this fly's in the face of what you felt was original on your car. I know you are a little sensitive to say the least on anything being non original on your car since it has been owned by you for such a long time. I hope this sheds some light in a positive way on the subject. Bob

 

No, you have explained it all very well. Thanks.

 

Hi to all on this thread. Here is proof to me that these forums are full of a wealth of people with great knowledge and experience. I recently purchased a new master cylinder from my local parts store. I had no idea that the master cylinder that came with my Shelby would turn out to be the original one until seeing this thread. Mine has the dimpel, Bendix wording and the round Hex head bolt.

I had my M/C all boxed up and ready to go back to the store as a core. Not anymore! I will be sending this master cylinder out for overhaul now that I know its the original one. Just goes to show you should never throw anything away or turn it in for a core without doing some research first.

Thank you Bob for the pics and great info and thanks to onelimegold for creating the thread.

Jim
#3000

 

Jim, thanks for the compliment. Glad I could help. Bob

 

Bob, I talked to the seller of the NOS 67 Shelby mc. that I posted the link to a few replies earlier. He said the bore is 15/16". Did some of the Shelby's use a mc. with a 15/16" bore? I've only found listings for a 1" bore on the 67-70 Shelby's.
Kenny

 

The 67 Shelby GT500 Add and delete sheet does not mention anything about the Master Cylinder so it would be the same as a 390 disc brake Mustang. The GT350 would be the same as a 289hp disc brake Mustang. I believe they got the 1" bore M/C. Bob

 

I just tore down my M/C. Bore size is 1" like Bob said.
Im going to send this out for a rebuild. Any suggests on a good builder?

Jim

 

I'm seeing people spending big money for the 15/16" mc's that are being listed on ebay as NOS Shelby and Boss9 mc's. I seen someone pay over $800 for one that was listed as a Boss9 mc. it's identicle to the one I bought with a 15/16" bore for $15.00
What is the correct Bendix no. cast into the bottom of the mc.
Kenny

 

casting number Bendix 2227161 with 1" Bore.

Jim

 

FYI Most of the time you can't read the casting. You should be able to take a 15/16 M/C and if you were going to have White Post or another rebuilder put a brass sleeve in it like they do you can have them make it a 1" bore. There is plenty of room to overbore them. I have done that before with wheel cylinders. I have never tried it on a M/C but it should be the same. Bob

 

Not sure what you mean but I sanded the surface rust of some and I can clearly see the casting number on the bottom of the cylinder along with the Bendix logo just like the one you pictured. This car only has 37k miles on it. I pulled the guts out the the cylinder and the bore size is 1". Why would I want to get a 15/16 and sleeve it when I have a good one for rebuild? Im confused at what your trying to advise.

Crap I cant upload pics on thei forum anymore. No clue why. I always get an upload error

Jim

 

As far as the casting number I was speaking in general terms for those reading that might be looking for a casting number in a bunch of cores and not be able to read it because the casting is poor and illegible. As far as the 15/16 M/C I was giving some options for others reading that might not be as fortunate as you in the search for a correct looking M/C. If you can at least find the right M/C with the correct stop bolt and marked"Bendix" that is most of the battle . The casting numbers are usually hard to read and since they are under the M/C once installed you will never see it again. I was giving a option so that if a person was to find the correct style M/C you can have it rebuilt to a 1" size regardless if it was that size originally or not. In judging the main test for a correct M/C is to feel underneath for the correct shape stop bolt. I have never used a mirror to try and confirm a correct casting number on a M/C or know any other concours judge who does in practice. You never have the time. It is nice to know you have a correct casting number on your M/C but In case you can't find one there is a alternative . I was trying to help advise that there is more then one way to skin a cat.

 

I sent mine to Karp's 66 N.Central AV Upland CA 91786. Ph # 909 985 0800. I got their name and address out of Hemmings Motor News.

Great work but they must use some rebuilding kit that does not have the correct bolt in the bottom.
I also had my original rear wheel cyls done. Stainless sleeved. I think I paid roughly $400 for the master cyl and the rear wheel cyls.