There are Moments where I genuinely want to thank God for giving me a Brain. I really mean that with all sincerity and humility. There are many times where I, when faced with a problem or issue, STOP what I'm doing... To think. And it can be frustrating, because I know that society at large tends to favor those who "spring into action." Or... As I would like to phrase it: They React! Act without thinking! This can be helpful if you are in the Army and people are shooting at you. But this is why they train.... So you do not have to think. Your training takes over.
But before I go down that rabbit hole, I want to bring things back to what this Blog post is originally about. The Humble Copper Crush Washer.
If you read the last post, you will note that I worked on fixing my front brakes on the Silver Eagle Subaru. And since it has been over two years since I last did a Brake Job, I don't have the muscle memory of a Mechanic (Or soldier) to take over on the details. I have to do things slowly and methodically... With plenty of time, Tools, new Materials and You Tube Videos to spend in it. I have no safety net, No back up, No "Hey buddy! Can you give me a ride to the Auto place for this part?" It is just me and my brain. ( And a little bit of previous experience... Just enough to give me that Dangerous "DIY Confidence.")
So, after bleeding the brakes for the first time ever... I took the Subie out for a test drive and the brakes worked. And that was the end of THAT story.
But... As with all things in Life... The story continued!
Monday Morning, I woke up to a fairly large puddle under the driver's side tire. My Brake line was leaking!
With a little bit of time to spare before work, I took the tire off and started trouble shooting. Turns out, the connection between the brake line and caliper was slowly weeping. (That is without applying the brakes under pressure!) The inside of the tire told a different story... The entire rim was "Painted" with brake fluid. This was more than a leak...
Now here is where I'm thankful for my "Stop and Do No Harm" thought process... Rather than crank down the banjo bolt to tighten it, I checked out all of my Torque specs to make sure I had done things properly. I pumped the brakes and reconnected everything... It still leaks. With time running out, ( I had to go to work.) I ask myself: what are the minimums I can accept?
I have to get to work. Check. Can I get to work? I Think so... With a manual transmission, I have driven to work before without touching the brakes. ( Down Shifting... It is a fun little challenge I play sometimes.)
I have plenty of Brake Fluid, so I will keep the reservoir filled. And I have all of my tools ready in the event I have to pull over. And I will research and Think about the problem until I can handle it on Tuesday.
The problem turned out to be the Crush Washers on that line. The previous dozen videos all glossed over the important "tip" that needs to be done when installing new crush washers. They just say to torque them to the right spec. They DON"T show you how to seat them properly.
It took me a while with the "right search terms" to find videos that address this issue. And many of them seems to contradict each other. So here is where you ask "Why?"
Why do you need to Hit it with a hammer? Why do you need new Crush washers every time" Why must you use Copper instead of regular washers? Why can't you just crank down the bolt tighter to make the leak stop?
I know there are lots of people who's answer to all of these questions is "Get a bigger hammer and hit it harder!" or tighten it until you pull the threads.... Sometimes that works! But in most cases, all that does is break things. And I can't afford to Break my Brakes! Other ones will tell you buy better parts. Take it to a professional. Use better tools and equipment. Etc. And I'm sure all of those points of view are valid. And are grounded in what has worked for them. (Like the guy who hates copper washers....)
I found one Video that seemed to explain the theory and Ideas behind the Copper Crush washer better than the rest. And answer the "WHY?" questions the best.
So... I hit the Bolt with the hammer. And that Helped! But it was still leaking. Noticeably less than before... But a leak is still a leak. And I find leaks unacceptable!
I purchased a rubber-steel hydraulic Washer Set from Amazon. But that was not going to arrive until Wednesday night. So I Still had two days to make it back and forth to work. So... That is what I did.
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| he old ones are too corroded. |
On Tuesday, I wondered if there was any other thing I could do to stop the leaking. Or if I could reuse the previous washers. Again, the Internet was split on this. Those who think only NEW washers can be used. Others who say "In a pinch, you can use the old ones."
But here is where they "Why?" question comes in. The Old washers can not simply be reinstalled. They have to be "reconditioned" And I found a video that showed me how.
Lightly sand the previous impressions off the washer. But be careful not to take off too much! Because then the Banjo Bolt will not seat properly. (Turn it too far and the brake fluid will not flow into the Caliper Piston.) Like a Ball Valve for your Plumbing.
And then there is the Annealing Process. Heat up the copper to make it softer. This will provide a better seal.
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| Banjo bolt removed! |
All of these things they did not mention in the brake videos. And are Kind of Important! If you don't want leaks. OR to strip out the threads of your brand New Caliper!
And so, yesterday... Under threat of rain and cold, I jacked up the Subie AGAIN! And removed the Washers. I found the old ones, but decided I would try to use all of the methods I had just discovered on the new ones. (By the way, I also clamped the hose and depressed the brake pedal, so the brake fluid did not leak all over my driveway again....)
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| Indented crush marks. |
I could see that my banjo bolts had, in fact, made an impression on the washer. While torquing it down, I was convinced nothing was happening. But you could clearly see the impressions.
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| Is THIS the problem? |
And that is when I noticed what was probably my problem.
A small indented channel across the surface on the backside was probably the reason I was not getting a good seal when torquing things down. DING DING DING!
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| almost gone. |
I found some sand paper and began the process. With only 120 grit and 1000 grit, it was a slow process. 120 grit takes off too much material and leaves deep scratches.
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| sanded and shiny! |
With the the washers now "resurfaced", I dug out my torch and annealed them. I was probably a little overly cautious to make sure I did not OVER-heat them. Only to orange or red.. not to white. But the difference was noticeable. I dropped the annealed one and it did not "Clang!" when it hit the surface. Kind of cool.
And so, with all of these "little things" finished, I reinstalled the washer and bolt. Torqued them down to the right spec and started things up.
No Leaks! HURRAY!
It is the little things that give you the most pleasure in life. The satisfaction of knowing how you unraveled the mystery and found the missing piece of a disjointed puzzle. I'm still baffled how I managed to get the passenger side caliper to work out without issue. And I guess that is why most of the videos leave out the whole "Hitting the Bolt With The Hammer" and "Annealing" process off their videos. I do not do enough brake jobs to know if a leaking brake line is common or not. But it would be a nice little tip to add to any of those previous videos.
So now I have a record of my lesson so my future self will not have to wade through an ocean of videos to refresh my knowledge of brakes. And maybe someone else will access this blog post and be able to glean tidbits of information to help them with their struggles.
A Simple Copper Crush Washer.... Not so simple. Or Unless you know the tips to make it so. And when you do, you feel like you discovered a hidden gem that everyone else has passed over or ignored. What better way is there to make every second count?




















































