Brake Hose to Caliper Sealing Theory

[Gary AAR]

I am working on reassembling the front disc brakes on my 70 Cuda.  When I was ready to assemble the brake hose (new reproduction part) to the caliper (original part to the car), I started to wonder how the brake hose seals to the caliper to prevent brake fluid leak.  Other brake related joints on the car always seem to have two mating flared surfaces that are forced together when the threaded fitting is tightened, thus forming a seal to prevent leaks.  The brake hose to caliper joint doesn't seem to have this.  The end of the hose fitting does have an inverted flare on it, but the caliper doesn't have a matching flare in the bottom of the threaded port (See pictures below).  So it appears the only mechanism to seal this joint are the threads, which doesn't seem right.  What am I missing?
Thanks for the help.

[Burdar]

There should be a copper washer under the hose fitting.  Make sure the area where the copper washer sits is free from defects like rust pits.  It will cause the hose to leak.  I had to sand out some rust pitting in the rebuilt calipers I received.

[anlauto]

Darren is right, they rely on the copper washer to seal

[Gary AAR]

Thanks for the answer.  I'll start looking for copper washers.  Anybody know of a good source for copper washers?

[JS29]

@Gary AAR  The copper washer should have been included with the new hose and or with the new calipers. I would get a hold of the source you acquired them from 

[Rich G.]

Any good auto parts store should have them. Bring the hose to be sure it's the right size.

[njsteve]

One thing to note about the modern copper sealing washers: some of them are only copper-plated steel or a much harder, copper colored alloy and they don't crush properly and they will leak. I have had to resort to using old copper washers that I slightly sanded to give them a new surface.

Just an FYI on the crappy offshore made washers. Here's a hint: if the copper washer sticks to a magnet...its crap.

[Jim AAR]

You need Copper Crush Washers, to ensure no leaks...

Measure the outside diameter of the thread, should be able to get them at any auto parts store. Just make sure they are crush ones, buy a few they are cheap and come in handy and should not be reused.

[Headjam]

My new replacement brake lines did not come with copper washers. I purchased Dorman 66250 washer kit. It has various sizes so you can find one size that fits your lines. They are not magnetic.

[Hood]

I installed new calipers and hoses on my cuda last summer and the original factory calipers/hoses did not have any crush washers on them. The new parts did not come with any crush washers either.  I do have a leak on the passenger caliper/hose so I am going to buy some crush washers.  Why didn't the factory use crush washers when making the car?

[MoparLeo]

The factory didn't install the hoses on the assembly line. These items were assembled offline, usually at the parts vendor locations, as sub assemblies and the rubber line was just attached to the chassis mounted hard lines. They used different, Industrial tools on these parts. It is only new/original once.

[Hood]

My new replacement brake lines did not come with copper washers. I purchased Dorman 66250 washer kit. It has various sizes so you can find one size that fits your lines. They are not magnetic.

I bought the washer kit and it stopped the leak I had. Happy, happy  happy.