Brake Line Questions

[bacelaw]

Hi all:  new to the forum and working on my new-to-me 41 Plymouth Woody Wagon.  I've searched through the archives, but here's my problem -

 

Someone previously monkeyed up our rear brake lines.  Does anyone know the flare/fitting size into the rear wheel cylinders?  I know the front are different, what size fittings are those?  I think they are both inverted flares, or should be.

 

Also, the rear axle tee block that doubles as a vent for the axle - anyone have a picture of what it should look like?

 

Thanks in advance!

Edited January 19, 2023 by bacelaw
Change

[Los_Control]

While many things change including the brakes .... many things stay the same.

Here is a photo of a 1949 truck. The lines are 5/16" coming out of the master cylinder into a T that feeds 1/4" lines to all 4 wheel cylinders.

 

I just feel if your woody wagon has 10" drums, master cylinder & brake lines would be the same. .... I could be wrong.

Here is how they are routed on a 1949 truck.

 

[bacelaw]

Thanks so much.  Yes, the wagon has 10" drums.  My problem is someone mixed metric and sae fittings in the rear and it's a mess.  That Tee fitting looks like mine, but mine now has damaged threads.  Any idea where to find one?

 

 

 

[MarcDeSoto]

You try to use a tap and die set to fix the threads if they are not too far gone.  I don't think anyone sells that part, so you might have to look for a junk yard.  

[joecoozie]

Sent you a PM

[chris 48 P15]

there are different types of threads for these fittings

i dont know what size they are parts maybe found at local auto parts store

replacement parts for these cars may be in metric threads

the fittings are supposed to be leakproof when done properly

you may also find this problem with fuel lines

[bacelaw]

I'm still struggling to find the proper setup.  My rear wheel cylinders have a brass fitting in them (pic attached).  I'm trying to find out if this is correct, and if it is, what threads/fittings are needed to button this up....or, if in the rear the brake lines can go directly into the cylinder without this brass on my '41 Plymouth.  Fitting size and thread count has me dizzy

 

 

20230119_100212.heic

[chris 48 P15]

yes definitely repaired

here is picture of parts manual for brake lines

 

 

[bacelaw]

1 minute ago, chris 48 P15 said:

yes definitely repaired

here is picture of parts manual for brake lines

 

 

Thanks Chris..so the brass is required?  It looks like 1/4 male pipe thread to a female flare fitting...I just dont know the size of the flare fitting and whether these brass are even available.  Thanks!

 

 

[Los_Control]

bacelaw photo

 

[vintage6t]

1 hour ago, bacelaw said:

Thanks Chris..so the brass is required?  It looks like 1/4 male pipe thread to a female flare fitting...I just dont know the size of the flare fitting and whether these brass are even available.  Thanks!

 

 

 

Going from memory, I believe my 41 has the brass fittings.

[kencombs]

1 hour ago, Los_Control said:

bacelaw photo

 

THANKS,  For translating the pic into something PC friendly.  I have no idea why Apple has to be so unfriendly.   And, they want to charge for the app for my PC.

[bacelaw]

25 minutes ago, vintage6t said:

 

Going from memory, I believe my 41 has the brass fittings.

 

Most people are telling me that brass fitting is correct...thanks.  No one yet knows the size, I think it may be 1/4" pipe threads into the cylinder and the brake fitting may be a 7/16-24 flare...when/if I figure it out I'll post results in case anyone else is stuck redoing a hodge podge of brake lines.  This forum is great.

[Los_Control]

I can add that I bought some of those fittings for my truck from a local auto parts store.

 

My original brass T coming from the Master Cylinder iirc was really a 4 way with 5/16" going in & 1/4" going out the other 3 outlets.

They did not have the 4 way, but I bought 2 brass T with 5/16" threads, then I used reducers that went from 5/16" threads to 1/4" threads.

They look a lot like the brass fitting above in photo, just different thread size. ..... Also the adapters were steel & not brass, but correct threads for the job.

 

Thats how I got around my brake lines, by going to T instead of 4 way & using adapters to get the correct size.

 

The vent line on rear end would probably be best to replace with good used.

Possible you could tap it out to larger size & use a reducer to drop it back to the needed 1/4" ... correct thread pitch is important when tapping out.

[Plymouthy Adams]

that is the industry standard flare reducer 1/4 -3/16  should be able to snag these from any local OTC parts house.

[MarcDeSoto]

I just did the brake lines in my 48 Desoto which should be the same as your 41 Plymouth.   All the brake lines in mine were 3/16" tubing with U.S. Standard threads.  There are no metric threads on brake lines in these old cars.  

[Los_Control]

I wonder what level brake job @bacelawis looking for .... A 1941 woody is pretty cool & they may be looking for a 100 point restoration with all factory parts.

 

While I have a beater with a heater .... I just pulled the brass fittings from the wheel cylinders & master cylinder .... brought them to the local parts store along with all the brake lines I could save.

I bought over the counter enough parts to put together a working brake line assembly. .... Really is not any more difficult then that. .... Kinda sorta.

 

I get confused on threads, so I'm reluctant to offer advice on proper thread size ..... just bring the pieces with you & get the size you need.

Working on my fuel system I know I need npt threads to fit my fuel tank, Ace hardware is selling me mip & fip fittings that work perfect.

I have zero interest in learning all the correct sizes, I will just forget them later.

I just suggest taking the parts you have to the parts store & get the lines that work for you.

 

 

[bacelaw]

@Los_Control I'm with you 100%.  I promised the previous owner that we would drive the wagon.  I plan to drive it all Summer, daily if possible -  the next owner can restore it to perfection.  While I'm here, I'll drive it.  

 

The rear brakes had a terrible mix of fittings that never worked properly. So, I was trying to sort out what's correct and what's not.  Apparently in '41 Plymouths had 1/4" brake lines in the rear.  The rear wheel cylinders don't accept a 7/16-24 flare, so an adapter is required.  The adapter is actually in the '41 parts book.  The adapter either has 1/4" pipe threads going into the wheel cylinder or 3/16-24 male flares,  and it allows a 7/26-24 flare fitting to attach. 

 

Thanks for everyone's help. I'll update once it's all put together

[kencombs]

51 minutes ago, MarcDeSoto said:

I just did the brake lines in my 48 Desoto which should be the same as your 41 Plymouth.   All the brake lines in mine were 3/16" tubing with U.S. Standard threads.  There are no metric threads on brake lines in these old cars.  

Except there have been reports of new replacement parts from somewhere other than the USA being supplied with metric tapping.   Examples of engine mounts, water pumps and wheel cylinders have been mentioned.  So, one should check when in doubt.

[vintage6t]

I think you already have your answer but just to verify this is the cylinder for my 41 Plymouth. Yes, it uses an adapter.

[bacelaw]

@vintage6t. That's exactly what I was looking for -  that brass fitting bottoms-out in the wheel cylinder and doesn't appear to need any copper washer or anything.  Thanks!

[sidevalvepete]

When you think a little about what you have here, looking at your picture, there is a cast iron wheel cylinder with brake line screwed into it that is steel. Without the brass fitting, the steel and cast together will in short order rust and seize. The brass keeps it all serviceable. I can imagine in our throwaway world today that this sort of consideration would not be given....

[joecoozie]

Sent you another PM

[Tired iron]

Im guessing you probably don't want to dig this deep into this, but I replaced my entire brake lines with the new easy to bend nicop lines.  I got a kit with plenty of tubing to do the whole car plus all the fittings for about fifty bucks.  Or for some more money you can get a kit with all the lines pre cut and flared.

[bacelaw]

Thanks for everyone's help - for future forum searchers, here's what worked for me.  The rear brake lines on my '41 wagon are 1/4" tubing.  The inverted flare/double flare fittings are all 7/16-24, both out of the rear axle block and going to the rear wheel cylinders.  However, the rear wheel cylinders have 3/8-24 female threads in them (for a 3/16" tubing) - you need a brass adapter at each rear wheel cylinder so the larger 1/4" tubing will plug into them.  

 

Advanced Auto, and probably all the parts stores sell an adapter that has 3/8-24 flare male on one end and 7/16-24 female on the other end to accept the brake line.  We didn't even need a copper washer at the wheel cylinders, because the adapter bottoms out nicely and tightly.  After some test driving, we could always add a copper washer if the brass isn't sealing at the wheel cylinder.

 

I eventually got nicop lines as @Tired iron suggested.   The nicop lines are crazy easy to work with, easy to bend, easy to flare, and are forgiving -even if the flare isn't perfect the material will mash together and seal.  

 

Thanks!