Help!
I just replaced the master cylinder on my 65 f100.
After everything was installed I discovered that the brake lights were staying on. I releived a
little pressure at the master cylinder line out
and the brake lights went out.
I replaced the brake light switch and that was not the problem.
I later realized that the brake pedal did not have
the free travel that it had before. I took the master cylinder back to the parts store and got a different one that had a deeper hole in the piston
where the rod goes and now the pedal goes almost
to the floor.
Any suggestions guys?

 

Your truck's original unit should be a single resevoir. There were several different master cylinders for the F-series trucks in 1965 and as equally many different push rod lengths. That can also be the source of your problem if you have the wrong rod. The Part Nos. for the 1965 F-series master cylinders are as follows:

C5TZ-2140-A (F100(4x2)w or w/o Booster)1" bore;
C5TZ-2140-H (F100(4x4) w/o Booster) 1" bore;
C5TZ-2140-B (F250(4x2) w/Booster)1-1/8" bore;
C1TZ-2140-B (F250(4x2) w/o Booster)1-1/8" bore;
C1TZ-2140-B (F250(4x4) w/o Booster)1-1/8" bore;
C3TZ-2140-J (F350 w/o Booster)1-1/4" bore;
C3TZ-2140-J (F350 w/o Booster)1-1/4" bore;
C6TZ-2140-B (F350 (Mod.84) w/Booster)1-1/32" bore;

It sure sounds like they gave you the wrong part twice now and with all of these possibilities it's no wonder. Unfortunately, unless you are buying NOS or from a knowledgeable afternarket supplier of Ford parts these numbers are meaningless to the counter-guy. There's no telling if the parts are boxed wrong either. I am assuming that they already took your core so you can't compare it to the replacement part they gave you. Unless you know for sure everything is original, you may have to go look at a few other trucks to get the right part. Measure the bore of the master-cylinder you now have; also measure the length of your pushrod from the center of the hole on the "pedal side" to the "push" end. Post that info.

Stock Man
1967 Galaxie 500 Convertible (HELP!---I need 15 x5 factory rims)
1967 F-250 FE 390 4wd
1966 F-250 I6 240 2wd LWB Flare Side
<a href="http://www.hometown.aol.com/tbeeee">http://www.hometown.aol.com/tbeeee</a>

 

Stock Man,
according to your information, there should only be 1 master cylinder for my truck.
The first replacement master cylinder looked exactly like the original one (single resevoir).
The only difference the second master cylinder
had was where the brake light switch mounts on the bottom instead of the top and the depth of the hole that the brake rod goes into.
Yes, unforunately the core I turned in is gone.
I guess I'm foolish for thinking these guy know what they're doing. I guess there's a lot of parts
for them to keep up with.
Here in the small town I live in there are very limited resouces, what do you recommend? I don't
mind spending more if it'll get me good stuff, but
this mail order business has me gunshy also.

 

Kikker,

There is one excellent source for the part that you are looking for, AutoKrafters, Inc. You can order a parts catalog right off of the web. You may be charged a core charge for a master cylinder, but I'm not sure. I hope that this works out for you.
Here's their web address:

Auto Krafter's, Inc.
<a href="http://www.autokrafters.com">http://www.autokrafters.com</a>/

Good luck!

Avatar

 

Hey Guys,
I've fixed the master cylinder problem. The second
master cylinder was the wrong part to start with
and the first replacement master cylinder had the check valve not working. So, they finally got one
that works properly.
Thanks for the help!

 

Yes there should only be one correct part for the job. By putting all the data before you I wanted to illustrate how easy it might be to have the wrong cylinder. They all look the same from the outside and will all appear to "bolt" up correctly. Who knows how carefully these assembly line remanufacturers examine the cores etc., etc.

I wouldn't recommend anything until we know you have the correct push-rod. You could order another MC and still have problems. Therefore, do yourself a favor and let's try to determine what parts you have now. Measure the bore of the master-cylinder you now have; also measure the length of your pushrod from the center of the hole on the "pedal side" to the "push" end. Post that info. It's the best place to start.

BTW all of my analysis assumes that the rest of your brake system is 100% and you correctly bench bled and installed the MC. I point that out for clarity sake not to insult your mechanical ability.

Stock Man
1967 Galaxie 500 Convertible (HELP!---I need 15 x5 factory rims)
1967 F-250 FE 390 4wd
1966 F-250 I6 240 2wd LWB Flare Side
<a href="http://www.hometown.aol.com/tbeeee">http://www.hometown.aol.com/tbeeee</a>