The Stovebolt Site Forums The Shop Area Engine Shop Brake lines - types of flares

I wanted to share a learning that may save other rookies (like myself) some headache when working with brake lines. Some of you experts I'm sure can clarify a few things.

On my '51 1/2 ton, rear brakes, I decided to replace the left wheel cyclinder as it was a different diameter than the right WC (15/16" vs 1"). I ordered a new WC from ClassicParts.com. I ruined 2 new brake lines trying to screw them into the WC. I thought I was cross-threading, so I pulled the WC so I could get a better handle on it. I actually had to put it in a vice in order to screw in the brake line. I knew this wasn't good.

I took the WC to O'Reilly, and the guy immediately identified the problem as the new WC taking a brake line with a "balloon flare" (rounded on the end), not a double flare (recessed on the end). The bottom of the hole in the WC was concave or sunken, so it could accept a rounded flare. The bottom of the hole on the old one was slightly convex, so it would fit into a double flare. Also, apparently, the threads on the fittings are different pitch between the two types of flares/lines/fittings.

I had no idea there are different kinds of flares on brake lines (this is the first brake job I've done in my life). So to anybody who may replace a WC, look at the bottom of the hole where you screw in the brake line. If it's concave (sunken), it takes a balloon flare (apparently, the odds are a new WC will be of this type); if it's convex (protruding), it takes a double flare.

Experts, please tell me if I'm spreading garbage here. In any case, there's one indisputable fact: I can't thread a new brake line with a double flare into my new WC, for wahtever reason. I haven't determined whether a ballon flare line will thread in properly, as nobody locally stocks those lines. ODD--new WCs take balloon flares, but nobody stocks balloon flares!!

Whhaaaatt???????
There should be a block that attaches to the back of the wheel cylinder and then the brake line connects to the block. All the brake lines I've seen on these trucks use a double flare. If you ordered a replacement brake line kit from the catalogs they would all be double flared.

So you're saying the brake line does not go directly into the WC? It first goes into this block? In a separate thread that I started, a person mentioned something similar, that there should be a 90-degree thingy coming out of the WC. But if this is true, why doesn't my other wheel (with original equipment) have this fitting, and why doesn't anybody at the auto parts store inform me of this?

I'm really confused. Is it possible for someone to post a picture of this fitting, or of any WC that uses one?

Thanks for your advice!!

D.J.

When I get a chance I'll scan some pages from the assembly manual and send them to you. It probably won't be until this evening some time. Page 81 of Jim Carter's catalog shows the blocks and attaching bolts used on the rear cylinders. If the other wheel cylinder doesn't have the block it's because someone cobbled it, as evidenced by the two different wheel cylinder sizes.

I wonder if it,s not the wrong or a defective cyl. If it used the bolt & block method it would be a larger hole & go way back. I havn't been under one of these lately but 51-55.1 uses the same cyl. I've never heard of a balloon flare. These lines were the same for 50 years or more till they started using metric sizes.

I think someone put in a wrong wheel cyl at some point?
Don't know what parts store you go to but bubble flares are available around here for a long time now.

Ahh. "Bubble flare" is the term. Sorry for the confusion. In any case, would you agree that a bubble flare and a double flare are not interchangeable? In other words, a part that accepts and is leakproof with a line made with a double flare would not accept or be leakproof with a line made with a bubble flare?

I shop at mostly NAPA, but O'Reilly's told me they don't stock bubble flared lines. Haven't checked with Auto Zone or Advance A.P. I know I sound like a moron, but I swear I'm having real problems, and I'm getting pretty tired of messing with anything brake-related.

I'll post some pics as soon as I read the instructions for using Web Shots. Never used it before.

The actual correct term is ISO Metric, used mainly on foreign (Asian) and later model domestic cars. They do not interchange with the older double flare. Any good parts store will have both in stock.

I don't think anyone asked but, do you have a stock 1951, 3100 rearend in that truck???? I'd agree 100% with Bill those type of connections wouldn't be on any wheel cylinder that would fit that model truck. The bubble flare is just the first part of the double flare before the final fold. I use an English flaring tool that makes either the bubble flare or the standard double flare. Same set of dies.
Denny Graham
Sandwich, IL

Maybe I'm missing something here, but have you compared the new cylinder with the one on the other side? It sounds like somebody's giving you the wrong part, even if the diameter is correct. I've never seen any American vehicle from the 50's, car or truck, that uses anything other than a regular double-flared line in the brake system. Some front wheel cylinders used an oddball seat for the flexible line, but all the solid-line hookups I've seen on rear brakes use an inverted flare.
Jerry

Something sounds fishy,
I too don't know why you would be given a wheel cylinder that uses a bubble flare fitting for your old Chevy truck.

Some wheel cylinders have an inverted flare and directly take a double flared line with a male threaded tube nut.
Others take a "banjo bolt and fitting" that then has the inverted flare for your line.
Others will be the metric bubble flare.

Not that it is relevant here, but a bubble flare "can" be approximated by using the first step of a double flare operation, but professionally done bubble flares are most often made with special flaring tools designed for just that.

Grigg

sounds like two or three things are going on here. After 60 years there is no telling what someone has done. It sounds as if someone has changed the wheel cylinders to one that does not use a bango fitting/block. He definitely has a problem with two different ones already on the truck. I just finished the rear brakes on my 52 1/2 ton. It uses the 1" cylinders and has the bango block/fitting that fits to the WC. As someone mentioned you can see the banjo block and bolt in the JimCarter catalog.

I have never seen a bubble flare on any truck that I have ever worked on. Can't even remember seeing one. If the new one just purchased takes a bubble flare take it back. They gave you the wrong one and 15000 bolters will tell them so!

Thanks to several of you (especially Jim Meier for the diagram), I now understand what Achipmunk is saying (the line can connect directly to the WC, or it can go 90 degrees into a banjo block).

On my truck, the brake line goes directly into the WC, no banjo block. I assumed this is how it always works, but you guys talking about this "block" tells me I have a non-standard situation. Why wouldn't my FLAPS guys make me aware of this?

The rear axle in this truck is, I assume, original. The truck has been in my family for 50 years, and nobody has worked on it for at least 30 years. However, my dad used it in his car dealership w/ shop, so there's no telling what kind of mods he may have done.

In any case, the wheel cylinders you get these days are different from the old (original?) ones on the truck. Some of you suspect I have the wrong part, but the one I got from ClassicPArts.com is the exact same one O'Reilly supplies (just $10 difference in price). This is the one causing me problems.

To reiterate, at the bottom of the hole into which the fitting goes on the old WC, it is shaped like a mound, which would fit neatly into the end of a double flared brake line. The bottom of the hole into which the fitting goes on the NEW WC is sunken, not mounded. THE NEWLY MANUFACTURED WCs ARE NOT CONSTRUCTED THE SAME AS THE "ORIGINAL" EQUIPMENT, by my observation.

Here's a link http://thumb2.webshots.net/t/52/652/8/50/80/2044850800103308622MCADGT_th.jpg to a pic of both WCs (sorry, I didn't know how to do that properly). I have not added or removed any parts, such as a banjo block or other. The top WC is the new one from ClassicParts.com or O'Reilly. A standard brake line will NOT thread into it. At bottom is the old WC. A standard brake line WILL thread into it.

At this point, I think I'll use the old 15/16" WC, because I'm not going to drive this thing enough that it will matter if it pulls a little when I brake. I've just wasted $30 on the new WC that I can't connect to the brake line.

Achipmunk, ClassicParts.com may have given me one that takes a bubble flare, but they may also expect me to use a banjo block. I just don't know enough about this to know whether they're wrong, or I am.

Thank you ALL for your help. You guys rock.

Do they offer a new wheel cylinder with the proper type of fitting, one that is not a metric bubble flare?

Just because it is what the parts place has, and what they think is right, and what they hand you, does not make it the right part..

Grigg

Grigg, good point.

I called the tech line at ClassicParts.com (supplier of my new WC), and told them of my problems. I was hoping they would have a record of numerous complaints/problems, but they did not. They say they've sold many of that part and have not had any problems.

O'Reilly A.P. supplies the exact same part. When I showed mine to the guy behind the counter, he said I had one that took the bubble flare (meaning I got the wrong part). He had to order one, and when he placed the order he told his guy to look into the hole to make sure it took the double flare. The guy said "sure". When it arrived next day, it was exactly like the one I already have, and the parts guy was [censored]. So he called his warehouse again and told them what he wanted, with emphasis. The warehouse said they don't have any other version.

So what I have is what an online classic parts store sells and what a national chain sells, so it makes me think I have the right part and just don't know how to install it. But how hard can it be to screw a fitting into a hole? A standard fitting doesn't fit this hole.

I'll learn more tomorrow from my NAPA guys. They're good. (But they didn't say anything about a banjo block).

One other thing: the new WC came with a copper washer, which I had no idea what to do with. But I understand a banjo block attaches to the WC with a copper washer.....

ol red,

I didn't read all the above posts, so maybe someone has shared this info with you already. I don't know 'nuttin' about bubble flares, but I found a site that has inverted flare to bubble adapters.

Look down the page a bit. They list Weatherhead part numbers. I don't know if this is what might work for you, but it looks like it could be the answer.

http://www.ffcobra.com/FAQ/brakelines.html

Stuart

If it came with a copper washer, and the surface around the threaded fitting on the WC is machined flat to accept this copper washer, than more than likely that is what you need, with the banjo fitting.
And what you think is the bubble flare inside is just the bottom of a drilled hole for the banjo bolt.

A brake line or fitting should easily screw in place before it bottoms out, it should not be hard to assemble.

Grigg

I second Grigg's response. Get a banjo fitting and screw it in the cylinder, it should solve your problem. No telling what has been installed over the years, but more than likely it was just something to keep it on the road.
Fred

I think this issue is resolved. I retract the whole "bubble flare" issue (which a FLAPS guy put in my head). This is a case of me not being aware of all the parts involved.

Grigg, you called it (and other folks in other posts, such as Unsafe6, have been on target). I have been trying to screw the brake line into the hole where the bolt that holds the banjo fitting goes. Special thanks to Jim Meier for sending a superb diagram of the assembly.

This is the first and only brake work I've done, and I assumed I had original components and that everything I installed should look like what I took out. Mistake. Neither of my rear WCs has a banjo fitting. In fact, my NAPA guy told me one of my WCs is from a '61 Cadillac!

Unfortunately, NAPA tells me they can't get these banjo fittings. The part is obsolete. So I may just put 15/16" WCs in (if I can find another '61 Caddy!), because they don't require banjo fitting. If anybody has a line on banjo fittings, you would make my day.

Thank you all for your help. Without TSP (The Stovebolt Page), I'd be lost as a fart in a whirlwind!!

With a Banjo block you will have a copper washer between the WC and the Blcok and also one between the block and the bolt that goes through the block and into the WC.
Since the body is off my frame I will try to get a pic tomorrow if you don't get it figured out.

Just as info....if you need a bango block on your wheel cylinder the brake line NOT screw or fit in the WC but will fit and screw into the block. The bolt that holds the block to the WC is a diffent thread than the brake line...am I making any sense?

I deliver parts for Advance Auto Parts part time and when I look up the wheel cylinder it gives a pic and bore ect....try them!
AND I have seen many parts BOXED wrong in the past couple years. So if the same manufacturer is doing them all stores will get teh wrong one!
Also, I doubt very few "younger" parts people even know what a banjo fitting is.....and some older ones don't!

Achipmunk, yes, you make sense. Your second paragraph describes my error: I have been trying to screw the brake line into the hole that takes the banjo block retaining bolt, which are different threads.

Interestingly, my NAPA guy says my new WC, which I got from ClassicParts.com, is the wrong one. O'Reilly A.P. sells the exact same one for the '51 1/2 ton. Very confusing.

I will check Advance A.P. for the banjo block. Thanks!

D.J.

Advanced AP here didn't have the blocks and couldn't even order them. Banjo block and connector block are the same thing.
I would bet the WC you got from ClassicParts.com is the correct one. I've dealt with them and they are very good, they also specialize in parts for older GM trucks.
The only supplier I've found that has the banjo blocks is Jim Carter. You can call their tech help line at 1-816-252-5857 to ask about parts.
Here is a link to a page from their online catalog showing the parts you need http://www.oldchevytrucks.biz/47_55/full.asp?page=83

Jim

ol_red: JimCarer has the blocks for about $20 each if they have not gone up and the bolts are about five bucks each.

Jim, I have to disagree about the connector block and the banjo block being the same. The connector block is the one that sits on top of the right rear axle and the brake line coming down the chassis rail goes into the middle.....then the the lines go out each side/end of it to each rear wheel(to the banjo block)

Olred: I didn't get to take a picture today but if you wnat one I will take a pic that shows the block on the rear axle and to the wheels.
Advance does not have the blocks but they have the little copper washers that go on the block and bolt if you ever need them.

I also sent you a PM.

EDIT: I just did mine but can't remember for sure so I have to go look BUT if I remember correctly the line from the chassis going to the connector block on the rear end is 3/16" and the lines coming OUT of the connector to the banjo block on the wheel cyl. are 1/4"....I think but don't quote me on that right now!!

The Factory Assembly Manual calls all them connectors not banjos. I had sent a few pages from the manual to Ol Red where they were labled as connectors and I wanted to make sure DJ knew what the manual called connectors was the same thing that everyone else was calling banjos. The truck shop manual states that all lines for the 1951 1/2 ton are 3/16.

Denny,

What year is that? It looks like Huck brakes to me.

Jim, I agree on the term used as connectors. Sorry I tried to be so technical. I'm gonna go out right now and take a pic.

I just went out in the shop and took these pics.
http://s140.photobucket.com/albums/r19/LutherParris/52Panel/?action=tageditmany

It my panel album but there is two pics. One showing the brake line coming off the rail, going to the "connector" and the two lines coming out of connector going to each side....
the other pic is a close up of the right side showing the brake line going to the bango "connector" which is screwed into the back of the wheel cylinder. Hope this helps. Mine is a 52 and I am sure it was originally like this.

Bango brass blocks are readily available at CarQuest in Canada same should apply for the USA..... about $20 each....available in single or Y shaped or as union blocks. Don't forget to buy the copper washer and the new special bolt (center core is drilled out to flow brake fluid) that attaches the brass block to the WC.

At todays' price for Brass blocks .....a scrounging visit to an old junk yard can be profitable.... I beleive Jimmy Carter also stocks them.

Bob
1940 Chev CMP

OlRED: if you need the blocks please send me a PM. I just may be able to help you out....unless you have a junk yard there that you can raid!
If anyone has them but needs the copper washers Advance Auto Parts have the washers on their "Help" isle. Have several different sizes.

Is the link I posted still not working?? If you get there click on my 52panel album and scroll down to see the pics of mine that I posted.....or I'll try link it again for all to see.

Thanks Achipmunk. Jim Carter has the block, or banjo fitting, but not the attaching bolt for a 1951. Weird. Off to the junk yard I go.