How many crush washers do I need to replace the front and rear brake hoses?

I'm getting prepared to replace my brake hoses and want to make sure I've got everything I need. I have not done this in about 25 years so I'm not entirely certain where all the copper crush washers are. I seem to recall there is one on each end of the rear brake hose, and two on the banjo end of the front hose. Is there another one on the body side of the front hose?

Also, I'm assuming these are all M10x16 - correct?

Thanks,


Don
 

EricH

Eric Hamilton
Moderator
The inboard ends of the hoses don’t use crush washers, they engage with the bubble flare fittings on the hard lines. So you need six total, one for each rear hose to caliper connection, and two for each front banjo connection.

Make the connections at the calipers before you make the connections at the hard lines.
 
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The inboard ends of the hoses don’t use crush washers, they engage with the bubble flare fittings on the hard lines. So you need six total, one for each red hose to caliper connection, and two for each front banjo connection.

Make the connections at the calipers before you make the connections at the hard lines.
Thanks. I'll pick 6 up tomorrow. The local NAPA store has M10x16 copper crush washers in stock.
 

LarryC

Curator of #10105275
You will actually want 8. 1 or 2 will fail to seal and you will need to try again. I use the aluminum ones from MWB and have had much greater success. Last time I tried to get M10x16s at NAPA it was a no-go, as in, they didn't know what I was talking about.
 

EricH

Eric Hamilton
Moderator
I've had much better luck than that with copper crush washers.... but I'd still buy some extras. They're the sort of thing that it's handy to have a few spares around. But I don't buy them locally, I get them from Bel-Metric.

Copper work-hardens very easily, and of course that's not something you want in crush washer. In theory new washers won't be work-hardened, but I anneal them anyways: heat them to a good glowing cherry red then dunk them in water.
 
You will actually want 8. 1 or 2 will fail to seal and you will need to try again. I use the aluminum ones from MWB and have had much greater success. Last time I tried to get M10x16s at NAPA it was a no-go, as in, they didn't know what I was talking about.
These guys had 4 in stock but said another box of 10 would be there by the morning. I got the same reaction you got from calling AutoZone and O'Reilly's. The dude at NAPA was totally old school fortunately.
 

EricH

Eric Hamilton
Moderator
To anneal always let the material cool slowly. Never quench.
True for most metals, but copper is weird that way. Quenching doesn't stop it from annealing, it just stops the surface from oxidizing as it cools. Of course if you don't quench it, it'll still be annealed - the only difference is that you might have to clean it up with a bit of fine grit wet-dry sandpaper on a smooth flat surface/
 
I got my hoses installed today. Managed to get by with using only 6 of the 7 crush washers I bought. I drove the car around the block for the first time since 10/30/1995 (Would have gone further if my tags had arrived from the DMV). Evidently, I have not driven any cars without power brakes since then. It was an unusual feeling to be stomping on the brake pedal that hard. The problem was confirmed to be the hoses since now the car will roll down a hill after letting my foot off the brakes.
 
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