cherry 65

My master cylinder has a casting code of FD3R, is this the date of manufacture?

Bill Irwin

Can't help on the code, but, it's my understanding the duel master was not available until 67. Bill.

Bluestripe67

I'm not sure about what you have being a manufacturing date, but if your master cylinder has the number 5467084 cast on the underside it would be a correct unit for dual master cylinder J50 power brakes. Dennis

cherry 65

I think 65 was the first year. The 65 master accommodates 3/16" brake lines. The 66 uses 1/4" lines according to NCRS' judging guideline book.

I appreciate you take a look.

cherry 65

The master does have the number 5467084 on one side, and the FD3R on the opposite side.

The NCRS judging guideline makes no mention of the number I would like to know more about.

cherry 65

Well, I figured out part of the number after looking at the placement of the code n the master. The F is directly over the front brake line port, and the R is over the rear brake line port. So the only remaining code to be deciphered is the D3.

vark_wso

They are just foundry codes used to identify the casting mold in use, shift of manufacture, and the like. Meaningless for date & judging purposes.

uncle427

Look very closely at the LH side, most do have a date code CAST into them, usually 2-3 digits, specified the day of the year cast, does not reference the year, some castings the characters, including casting number and foundry marks are more "distinct"

Also keep in mind although only used in production for 2 years, it was available thru GM into the early 70's, so date code could be the 254th day of 1972, but it would not matter as the year is not referenced. If you are REALLY detailed, be sure whatever the date is, does not fall on a weekend or holiday for the year you want to use it on!

Try doing a search on "other" corvette forum, plenty of details there, or send a good pic to me and I will try to help
Bill

cherry 65

Thank you, I will send some Pix.

Bob