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1970 Opel Gt - Purchased July 1972 - Chartreuse - restored - 3000 miles as of 02-16, 2021 -
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Discussion Starter · #1 ·
Have already replaced the Master Cylinder and Brake Booster, larger version from OGTS along with the brake booster hose and just ordered the stainless braided brake lines, pack of three, the new clips, and the j-tubes from OGTS as well as the caliper rebuild kit. I decided to go with Amazon for the copper/nickel brake line from Carlson 3/16 Brake line - and the 10X1 mm inverted flare fillings. So I believe that I have everything covered except I need to order new bleeder fittings and need to know the size of the bleeder fittings- what is the proper size to replace the original as the originals are pretty well chewed up regarding the nut and with everything else being new just want to complete the set. I know the size of the nut is smaller than the other fittings but just not sure of the exact specifications. Thanks for you assistance. Hoping to add that to my Amazon order this evening and will then, to the best of my knowledge, have everything I need to have a completely new brake system. Thanks.......
Best Regards, Carl
 

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Discussion Starter · #3 ·
I was unable to get confirmation on that as the supplier, on Amazon, asked to put in the auto information and the response was that the product did not fit an Opel GT, not sure I believe that but..... I have been on a buying spree lately, unusual for me, but has been kind of fun, because I signed up for a free month of prime - and free shipping. And have been trying to cover my bases on things I may need in the next 3 months, regarding the GT projects and of course the wife has had some input as well. Anyway, perhaps my best bet is to just take one to the autosupply store to make sure I get the right match. I was hoping someone out there has purchased them and remembered or had the information available. I did not see them on OGTS but could also ask Gil as he may have them in stock as well.
 

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Opeler
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I was unable to get confirmation on that as the supplier, on Amazon, asked to put in the auto information and the response was that the product did not fit an Opel GT, not sure I believe that but..... I have been on a buying spree lately, unusual for me, but has been kind of fun, because I signed up for a free month of prime - and free shipping. And have been trying to cover my bases on things I may need in the next 3 months, regarding the GT projects and of course the wife has had some input as well. Anyway, perhaps my best bet is to just take one to the autosupply store to make sure I get the right match. I was hoping someone out there has purchased them and remembered or had the information available. I did not see them on OGTS but could also ask Gil as he may have them in stock as well.
I just went out and measured the bleeder from an old GT caliper with a micrometer and a metric thread gauge.
It is indeed a 7mm diameter with a 1.0 thread pitch.
 

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1970 Opel Gt - Purchased July 1972 - Chartreuse - restored - 3000 miles as of 02-16, 2021 -
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Discussion Starter · #5 ·
Now that I have a new brake booster - new master cylinder - and rebuilt calipers which includes stripping and painting with engine paint I am ready to move on the installation of new brake lines. Have decided to start at the back of the car, that's right, the easy part, where I can develop my learning curve for the bending and the installation of the new lines. I am actually looking forward to this part of the project for one reason, everything is easy to get at.After a lot of research I have decided to go with the copper/nickle brake lines that are easier to bend and will not rust. I have also found and read that they are easier to flair and that they seal really well. I chose the Carlson brand as it is made in the states and looked like a good solid product at a reasonable price and I have read articles of other suppliers/Chinese, that were just cooper coated steal and of course still prone to rust, so choose carefully in the event you decide to go this route. Another reason I chose the cooper nickle, besides the fact it is easier to work with and more durable, is that it can early be polished to a high luster. Guess that is not something important to some people however If I can make something look better I will usually choose that route. I used some Mother's mag aluminum polish and with just a little effort by hand ended up with a very nice looking brake line, shinny, not dull like cooper that has oxidized over time . I plan to give it a clear coat after I bend the pieces just prior to installation and expect years and years of not just good service but a nice look too. I really like the look, not that it will be see by very many people but why not - I have the time. Yesterday I reinstalled the rebuilt/repainted brake calipers and the new stainless steel hoses to replace the 21 year old rubber hoses, so when I finish this new part of the project the brakes will be 100 percent, which is always a good thing when talking about brakes/stopping power....

Rebuilt and refurbished caliber:

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Check out the look of the new cooper/nickel line with a couple of pieces polished.


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Just starting this part of the project so will follow up with more information on how it went and some pictures.
 

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Discussion Starter · #6 ·
As always the more I get into a project the more I get into it. Hoping that some of this information will help someone else in the future as they may stumble into some of the things that I have. I started bending brake lines today, actually one, much more difficult that I had imagined. But the real story today was the fact that I decided to double check the rear brake cylinders and over all condition of the rear shoes, etc. Glad I did as I actually expected to find everything in great condition as I had rebuilt them or so I thought around 22 years or 3000 miles ago. I started on the driver's side and this is what I found. One of the things I have mentioned before is when I started the restoration in the mid 1990's the goal was to get the car back on the road however with that said I did go into a great amount of detail in most areas However not all and I am now going back to correct those things that I missed along the way.

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What a surprise - again thought I had cleaned all of that out but the picture tells a different story.

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Turns out that I had purchased a rebuild kit however it did not contain new pistons which as you can see in the picture they have lost a lot of that chrome polished look unlike the pistons from my front calipers. additionally I am thinking that all that gunk is a combination of rust and brake fluid, however the bores were still in good shape. I ordered new replacement cylinders today from OGTS. The pistons tell story and the end of the left tip showing leaking and corrosion, none of the leaking was visible on the outside of the unit...

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I also noticed that the wear on the brake shoes looks a little strange as I am pretty sure that the pistons were not engaging very well, and uneven wear resulted on the shoe. I also discovered that the emergency brake lever was almost frozen - looked like it may have been modified as the rivet appeared to have been changed - some lubricant took care of that and I expect my emergency brakes to work much better as a result of the lubrication and new cylinders, part # 4014
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Tomorrow I will check the other side and dismantel clean and rebuild over the weekend.
 

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Über Genius
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The pistons aren't supposed to be shiny. They're cheap metal. They can be cleaned up and reinstalled most of the time if you can get the bore mirror smooth.
The easiest way to get a "rebuild kit" is to purchase wheel cylinders that fit a different car but have the same bore. I believe the bore is 15mm. I used to rebuild them all the time and could just pick up the cups at the local parts store. Sometimes I had to settle for 5/8" cups if they were out of 15mm.
 

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Discussion Starter · #8 ·
Thanks for the heads up but I figure for 25 bucks apiece I am just going to go new. Pretty sure a little fluid was getting by the driver's side front piston as there should not be corrosion in that piston cup like that, Right? And that corrosion was affecting movement. Don't want to repeat that. All the rubber parts were new and still in good shape.
 

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Opeler
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RockAuto(dot)com:
Raybestos Wheel Cylinders - RAYBESTOS WC37245 $13.32 each plus S&H and Tax.
Limited Lifetime. Warranty covers defects in materials and workmanship.
 

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Discussion Starter · #10 ·
Thanks for the heads up Lindsay that is an excellent price. Too late however as the ones I ordered on Thursday deliver tomorrow. I have purchased 85% of my needs from OGTS over the past 26 years and I continue to do so because Gil has also taken the time to give me a lot of really good information/instructions to help me solve problems - he has also taken back things that did not work correctly without an issue. I like the fact that someone, at OGTS, always answers the phone and that they ship the day you call. Great customer service. I am getting near the end of my restoration, I think, and it is nice to deal with someone that I know and now consider a friend.
 

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Discussion Starter · #11 ·
Rear brake job continued today 3/26/2021:
  • Fabricated brake lines for the three rear feeds - middle line/stainless steel hose to the tri-junction at the differential and the left and right lines to the wheels, I think I am finally getting the hang of this but therein lies the problem, the minute you get good/adequate at something like this the job is over and it is unlikely that this new found skill will ever be used again, at least for me as this is my last and only project car - I did however enjoy the learning experience
  • I ended the day by getting ready for tomorrow and have cut the pieces for the main feed from the master cylinder to the back feed, at the differential, for the rear wheels, and I have cut the piece for the drivers side front caliper, which I figure I can do after removing the alternator, coil, and voltage regulator, saving that for last - but still feel that it will be a challenge - unfortunately I do not plan to replace the line to the passenger side front caliper as I just don't see how that is possible without pulling the engine - if someone knows the "secret" please let me know - I just don't want to have to pull the radiator, etc
  • After pulling the passenger side rear brake cylinder I have confirmed that both right and left cylinders are leaking around the pistons = not a lot but enough to be problematic and a good time to replace the units - the pistons were all worn and slightly corroded, just enough to leak a little and they were not going to get any better, I should have replaced them when I serviced them 26 years ago

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Dismantled and cleaned up and coated - always feels good
  • 434320
    Pictured below is one of the rear brake lines, the only one that had exterior rust - this tri-joint is interesting and with the 13 MM screw that holds it in place gives you the ability to loosen it and make it easier to fit the fittings/screws into it.. Without this adjustable feature getting the fittings to screw into the tri-joint would be almost impossible. I plan to remove this and clean it up as well as blow out all the lines and fittings before reassemble. Currently I have all of the new pieces in place but will remove them all tomorrow to polish the cooper tubing and them spray with diamond clear to keep them from oxidizing back to the original appearance. This feature will not be seen by many but it is kind of neat to have order among all of the dirt and Chaos under the car.
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Tomorrow is another day...............................................Can't wait........................
 

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I have yet to see Opel rear wheel cylinders that don’t get pitted and leak, new shoes, new cylinders is a good rule of thumb in my experience, when you put the new shoes in those pitted holes that used to reside inside of the cylinder become exposed, glad to see your replacing them.
 

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Discussion Starter · #14 ·
Today was very productive 9:30 till 4:00 - Polished some things and sprayed with clear coat and installed. Looks a little different compared to the last picture I posted above. I liked working with the cooper lines as they were easy to bend and to flair - have my fingers crossed that all my flairs were good - had only done one before and no issues with that one so I feel pretty confident. New rear brake cylinders arrived today and I have the drives side installed, tomorrow I will move on to the passenger side. I then plan to run the cooper line from the rear rubber/stainless steel connector to the master cylinder and then the master cylinder to the driver's side brake caliper. That will complete the brake project. More pictures hopefully tomorrow.

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434347
 

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Discussion Starter · #15 ·
More work on the rear brakes today had to reassemble everything and I had forgotten how difficult it is to get those two springs back in place - In the past 48 years I think this was only the third time I had done that job so I had pretty much forgotten how to do it. Both rear cylinders are complete with the brake adjustment bolts on the back of the drum set properly. All of the new cooper lines on the rear of the car are connected/installed and ready to go. I have laid in place the long section from the front/master cylinder area to the rear connector and flared the front connection so tomorrow I will connect the front and flair the back part of the line, while under the car, and connect that too. Then the driver's side caliper will be the final step. I have the line flared and have connectors installed on the line ready to put it into place, just have to remove the alternator, etc to make room to get in in there. I expect to finish tomorrow. Just have to go out and get some brake fluid and 4 stainless steel bolts to change out on the rear cylinders bolts as those original 5 year old bolts are pretty much rust. Below is my last flare for the day. Everyone cross you fingers that there are not leaks.....

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Discussion Starter · #16 ·
This fitting and installing brake lines is hard work but rewarding. This copper tubing is so much easier to work with than the steel. I fitted the long line today that took much more time than I thought it would but it was so satisfying when I was able to align the connectors and screw them in by hand - not an easy task when dealing with the master cylinder and I could not imagine doing that with the steel tubing. Anyway a couple of pictures of the mid-line and the rear wheels. Not quite done.......


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434368
 

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Discussion Starter · #17 ·
Finished the brake project today - removed the alternator, coil,voltage regulator, vacuum advance unit, distributor cap and first spark plug wire and removed and replaced the driver's side brake line which was much easier that I had expected. The copper lines ability to bend easily really made the difference and actually fit better than the original line, no way I could have gotten the same results with steel line as I did all of the bending by hand. You cannot exactly measure a piece like that so it becomes a bit of a guess and I got lucky and was right on - actually could have use an inch more but it works. If anyone works with this copper line some of the reviews suggest you don't need to tighten as much when making the flares or when putting in the connectors as you may crush the copper tubing - not true - like steel you still need to get that very thigh fit connecting to each wheel or the master cylinder as a hydraulic fitting is a hydraulic fitting don't care what material you use you need a very tight fit. I know that because I had some leaks however with a tighter fit all is well - I bled the brakes, with the help of my wife pumping the brake pedal. Road test tomorrow...
Before and after pictures of the master cylinder. Don't know what is next may take a little time off. Cheers...

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434417
 

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Opeler
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Finished the brake project today - removed the alternator, coil,voltage regulator, vacuum advance unit, distributor cap and first spark plug wire and removed and replaced the driver's side brake line which was much easier that I had expected. The copper lines ability to bend easily really made the difference and actually fit better than the original line, no way I could have gotten the same results with steel line as I did all of the bending by hand. You cannot exactly measure a piece like that so it becomes a bit of a guess and I got lucky and was right on - actually could have use an inch more but it works. If anyone works with this copper line some of the reviews suggest you don't need to tighten as much when making the flares or when putting in the connectors as you may crush the copper tubing - not true - like steel you still need to get that very thigh fit connecting to each wheel or the master cylinder as a hydraulic fitting is a hydraulic fitting don't care what material you use you need a very tight fit. I know that because I had some leaks however with a tighter fit all is well - I bled the brakes, with the help of my wife pumping the brake pedal. Road test tomorrow...
Before and after pictures of the master cylinder. Don't know what is next may take a little time off. Cheers...

View attachment 434415

View attachment 434417
Job well done. You’re making great progress and making me envious of all of your triumphs. Onward and upward!
 

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Discussion Starter · #19 ·
Eric, Many thanks for your kind words and encouragement. That helps, as we all know it does get frustrating at times. But the accomplishments/achievements are what keeps us coming back. I am going to take a break and get her all spiffed up and hit some local car shows starting Saturday with coffee and cars. I then see a couple in the general area in April and May and have not really started looking yet. But with all of that work its time to show her off a little.... And as of next Thursday full vaccinated and ready to get out in the world again, without the worry. Actually taking Susan for lunch and a movie this Sunday - first big screen experience in over a year and I use to go pretty close to once a week.
Best Regards, Carl
 
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