Vintage Mustang Forums banner

1 - 17 of 17 Posts

·
Registered
Joined
·
2,724 Posts
Discussion Starter #1
So my brake distribution block had the brake light plunger stuck to one side, the side where you can't push against it to recenter it of course. So, I performed the following fix:

I first drilled a #21 hole in the side, tapped it for a 10-32 brass machine screw and used a 2" screw threaded into the hole to drive the plunger back to center:

http://i236.photobucket.com/albums/ff223/aolshove/BrakeFuelLineInstall024.jpg

Then I removed the screw and cut it slightly longer than the threaded hole:

http://i236.photobucket.com/albums/ff223/aolshove/BrakeFuelLineInstall025.jpg

Then I coated the screw with blue loctite and used a thin nylon washer and tightened the screw as much as I could by large screwdriver:

http://i236.photobucket.com/albums/ff223/aolshove/BrakeFuelLineInstall027.jpg

So, do you think this will hold? I know that hydraulic pressure is a special kind of beast but this feels like it should hold compared to the large threaded adapter that goes into the other end. The only thing I can think of that might make it better might be a 10-32 copper crush washer. What do y'all think? Try it or toss it and buy another? Thanks.
 

·
Registered
Joined
·
1,066 Posts
looks good, probably will work only question is will brake fluid eat the loctight and nylon?
Bolt it up and mash the pedal and see what happens.
 

·
Registered
Joined
·
1,525 Posts
I would put a copper crush washer on it. And couldn't you just push the plunger out through one of the holes at the end instead of tapping a hole? I was thinking there was a hole at either end?
 

·
Registered
Joined
·
2,724 Posts
Discussion Starter #4
02Lightning said:
I would put a copper crush washer on it. And couldn't you just push the plunger out through one of the holes at the end instead of tapping a hole? I was thinking there was a hole at either end?
Thanks, I think I'll go try to find a #10 copper washer. There was just one hole at one end into which an adapter was threaded.
 

·
(actually Slim Jr now)
Joined
·
24,597 Posts
Looks like what you have is the drum brake set up. May be part of the confusion.

Far as thread sealing IMO that should work fine if you got the threads clean and used
Loctite primer, or you used a Loctite that doesn't require an active metal.

IMO a copper grooved washer is more likely to leak! IIRC they are normally used where
absolutely flat contact is obtained.
 

·
Registered
Joined
·
5,000 Posts
Did you clean the spool off? If you take the fitting that is in line with the spool out you could have used a pair of long chain pliers to grab the nipple on the end of the spool. Heat, wiggle, repeat. You would need to replace the x-rings (o-rings will do in a pinch) and the copper washer on the fitting. To really seal up the hole you drilled, you could solder it up once you have disassembled the entire assembly. Not just a little solder either. Or if you use a brass screw, you could heat it up and solder the screw in place. I do not know what compatibility Loctite has with DOT3 or DOT5 depending on what you are using, but I would look that up.
 

·
Registered
Joined
·
1,525 Posts
slim said:
IMO a copper grooved washer is more likely to leak! IIRC they are normally used where
absolutely flat contact is obtained.
They use copper washers on banjo bolts all the time for the flexable brake lines.
 

·
Registered
Joined
·
2,724 Posts
Discussion Starter #8
ylexot said:
... Or if you use a brass screw, you could heat it up and solder the screw in place. I do not know what compatibility Loctite has with DOT3 or DOT5 depending on what you are using, but I would look that up.
Oh! I hadn't considered soldering the screw. That might work best if I'm careful to get good flow. I'm just worried about the rubber parts on the spool getting damaged by the heat.

Regarding brake fluid vs. Loctite, according to their Data Sheet for the 242, it has withstood brake fluid for a 1000 hour test at 71 deg F and maintained 100% strength so I'm probably okay.

Thanks for the thoughts guys. I'd like to do this right the first time to limit the possibility of having to drain the brake system after I get the car together.
 

·
(actually Slim Jr now)
Joined
·
24,597 Posts
Used those copper washers working on most of my collector car brakes for around 40 years!

Those banjo fittings are designed for this. Use special soft copper washers and the
force (psi) on the washer is undoubtedly a lot more than you can get with a 10-32 brass
machine screw! Just my opinion!
 

·
Registered
Joined
·
176 Posts
When in doubt (especially with the brakes) replace. Your fix seems pretty ingenious, but I don't know that I would feel that confident cruising at 60mph approching the next off ramp. What if it fails the test?
 

·
Registered
Joined
·
12,155 Posts
Not sure I'd trust the threads either. I'm having a hard enough time dealing with the fact I have a Tee for my brakes instead of a dist. block with a safety valve.
 

·
Registered
Joined
·
2,724 Posts
Discussion Starter #13
coda618 said:
When in doubt (especially with the brakes) replace. Your fix seems pretty ingenious, but I don't know that I would feel that confident cruising at 60mph approching the next off ramp. What if it fails the test?
Honestly, I'm not worried about complete failure. It would take A LOT of pressure to push a 10-32 screw straight out and the threads with it. I'm more worried about leakage around the threads thus dripping on my pretty new paint. At any rate, to answer your "what if", I would lose my back brakes and the fronts would still do their thing since the fix is on the rear side of the dist block. Initial tests will involve me romping the crap out of the brake pedal and looking for leaks. If there's even a hint of seepage, I'm swapping it out for a new block.
 

·
(actually Slim Jr now)
Joined
·
24,597 Posts
While we're doing what if's...if the o rings on the shuttle fail completely you now have
that plastic switch that's screwed into the housing...pressurized!

If the screw (that you inserted) threads leak you'll get a little dripping on your
nice fender apron paint.

What bothers me more is that block indicates you have front drum brakes!
 

·
Registered
Joined
·
2,724 Posts
Discussion Starter #15
Slim, those are very good points that I hadn't considered. I'll admit my ignorance and cavalier attitude in the prior post.

The front brakes are currently rebuilt disc brakes from a 71 Ranchero (untested). I'm going to use a 74 Maverick MC and an external prop valve in the rear brake line after the dist block. Since you seem to be very knowledgeable, would you offer an opinion as to this plan, taking into account the current dist block fix? I'll replace it rather than risk my life to it but not just for the sake of "better safe than sorry". Have you ever seen the plastic switch blow out on a distribution block? It seems like a pretty serious flaw that nobody has mentioned before. I have trouble believing that of all of the original distribution blocks out there, the seals have failed to that extent including this one I've worked on whose spool has been off center for God knows how many years.
 

·
(actually Slim Jr now)
Joined
·
24,597 Posts
aolshove said:
Slim, those are very good points that I hadn't considered. I'll admit my ignorance and cavalier attitude in the prior post.

The front brakes are currently rebuilt disc brakes from a 71 Ranchero (untested). I'm going to use a 74 Maverick MC and an external prop valve in the rear brake line after the dist block. Since you seem to be very knowledgeable, would you offer an opinion as to this plan, taking into account the current dist block fix? I'll replace it rather than risk my life to it but not just for the sake of "better safe than sorry". Have you ever seen the plastic switch blow out on a distribution block? It seems like a pretty serious flaw that nobody has mentioned before. I have trouble believing that of all of the original distribution blocks out there, the seals have failed to that extent including this one I've worked on whose spool has been off center for God knows how many years.

I'm just familiar with cars I own or have owned! Never modified the brakes on one of my cars.
You'll note from my sig pic I've had my '68 vert for 31 years. It has power brakes...disc fronts.
The shuttle stuck at one end years ago. Someday maybe I'll fix it. IMO rusted brake lines are
top danger. Next is leaks resulting in empty master. I installed all new brake lines
a few years ago and check the brake fluid level regularly. Don't drive with a soft pedal which
indicates something is wrong!

Hey I had a 70 Maverick, base model, drum (no) brakes. Didn't drive as tho I had aircraft
brakes. Never hit anything...allow for what your driving. For a couple years in the
70's my 37 Ford (mechanical brakes) was my daily driver.
 

·
Registered
Joined
·
1,208 Posts
I had the same problem on my 69. I worked from the other end, drilled a small hole in the plunger and threaded a small screw in and pulled it out that way. Worked well, no extra external holes to worry about leaking... Plunger was stuck pretty well in there. Must've been that way for years...
 
1 - 17 of 17 Posts
Top