Copper crush washer; which is better thick or thin

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jawbone

jawbone

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Am trying to finish up install of slider type calipers on 68 Barracuda. Am working at termination of flex line at caliper. The crush washers I received were very thin so I opted for some thicker ones but cannot get them to stop leaking. Are the thin washers the way to go or are they just the cheap stuff sometimes supplied these days. Did not like the banjo bolts either so elected to purchase others a little longer and more substantial so I can crank it down real good. Anyone out there listening with experience on this. If I opt for the pin type calipers, they make use of copper crush washer as well so I really need to find my error. Thanks for any support. Jeff

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I have been told that a lot of the new copper washers are too hard. You can heat them with a propane torch and then let them cool to anneal the material somewhat. I ended up using some "good" used washers on my brakes when I had the same problem.
 
It's more about the material being soft enough than it is how thick it is.

But realistically, you only need the crush washer to be thick enough to make up for any imperfections between the surfaces. Meaning you should be able to use a very thin washer.
 
72bluNblu said:
It's more about the material being soft enough than it is how thick it is.

But realistically, you only need the crush washer to be thick enough to make up for any imperfections between the surfaces. Meaning you should be able to use a very thin washer.
Click to expand...
Hi Bryan, It's a borderline determination if the washers provided are up to the task of overcoming the factory cast ring ridges. Will not hurt to try of coarse but only have one try at this for the bleeder will not seal on one of the calipers as well. If necessary to switch to pin style caliper and the thinner style crush washer performs successfully, I'm without new thin washers. Was trying to determine my error prior to swapping if necessary. Even though the thicker washers are advertised as crush washers, they are much thicker than what was provided. I understand softness counts. May be 1973dust has the right idea to soften the washers that I have plenty of and see what happens.
 

1973dust said:
I have been told that a lot of the new copper washers are too hard. You can heat them with a propane torch and then let them cool to anneal the material somewhat. I ended up using some "good" used washers on my brakes when I had the same problem.
Click to expand...
Think you have something here. Won't hurt to try. Have plenty of thicker style crush washers.
 
I've resolved this problem many times by either striking the top of the banjo bolt squarely once assembled and tightened, and then re-tighten it several times. It looks like you won't be able to get a good strike with the caliper bolted in place, so remove the caliper place it on a block of wood or something, and strike the banjo bolt squarely with a good blow. You will know if the strike was sufficient if you can tighten the banjo bolt more.

I've also just tightened, loosen and re-tightened the banjo bolt half a dozen times to get the bolt to seat into the copper washer during the process.

The annealing process eluded to above is another step to get a proper seal. Getting the copper red hot and allowing it to cool without quenching is a good first step, as well.
 
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Annealing the thicker washer should work, at least to a point. Definitely worth a try.

As far as the thickness goes I was just pointing out that the hardness of the crush washer is usually the more important factor. They have to be thick enough to bridge the gap if there's one there, but the thickest washer isn't necessarily the best or anything was my original point.
 
jbc426 said:
I've resolved this problem many times by either striking the top of the banjo bolt squarely once assembled and tightened, and then re-tighten it several times. It looks like you won't be able to get a good strike with the caliper bolted in place, so remove the caliper place it on a block of wood or something, and strike the banjo bolt squarely with a good blow. You will know if the strike was sufficient if you can tighten the banjo bolt more.

I've also just tightened, loosen and re-tightened the banjo bolt half a dozen times to get the bolt to seat into the copper washer during the process.

The annealing process eluded to above is another step to get a proper seal. Getting the copper red hot and allowing it to cool without quenching it is a good first step, as well.
Click to expand...
Have watched a youtube video making use of hammer and striking the head. Good call on that and the annealing process. Keep hearing about it, Guess it's time to try. Thanks for your comment.
 
72bluNblu said:
Annealing the thicker washer should work, at least to a point. Definitely worth a try.

As far as the thickness goes I was just pointing out that the hardness of the crush washer is usually the more important factor. They have to be thick enough to bridge the gap if there's one there, but the thickest washer isn't necessarily the best or anything was my original point.
Click to expand...
I had understood your original comment and thanks as always. May be I put too thick of washer even though designated a crush washer. Will try the annealing process on some newer ones and see what happens. Meanwhile, have been cycling from loose to tight multiple times as noted to do by jbc426 before I proceed to annealing. Has shown good results. May be between the two processes I can get this stopped. Thanks again.
 
I like the thick ones I've had trouble with the thin ones being to hard and leaking
 
1973dust said:
I have been told that a lot of the new copper washers are too hard. You can heat them with a propane torch and then let them cool to anneal the material somewhat. I ended up using some "good" used washers on my brakes when I had the same problem.
Click to expand...
THIS!! THIS RIGHT HERE!!!

Also, tighten it some, tap the bolt with a hammer/ mallet, then retighten a couple of times, test, etc.
 
I've seen it where the caliper area was not machined very good or machined at all. Or heavy sand blast on sealing surfaces.
 
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I had the same issue last year. Annealed a variety of copper washers until two worked. Frustrating but no leaks now.
 
Some specifications for brake line gaskets or washers.
Chrysler part number 6030084 used on Chrysler slider caliper hoses from 1973 to the late 1990's.
Measurements taken from nos copper washers Chrysler number 6030084.
.081 inch thick, banjo bolt 7/16 diameter.
Used or crushed thickness .075 inch.
Used thickness may vary depending on torque used on banjo bolt.
 
townsend said:
Some specifications for brake line gaskets or washers.
Chrysler part number 6030084 used on Chrysler slider caliper hoses from 1973 to the late 1990's.
Measurements taken from nos copper washers Chrysler number 6030084.
.081 inch thick, banjo bolt 7/16 diameter.
Used or crushed thickness .075 inch.
Used thickness may vary depending on torque used on banjo bolt.
Click to expand...
The washers supplied were .031 inch thick. The ones purchased separately were .050 inch. Thanks for the response.
 
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