Kurzen

Hey. I am a newbie to RX's. But been around cars for a while so familiar with old cars and shade tree fixing. I just got my hands on my friend's family 1980 RX 7. Been in the family since new but needs some attention. The left front caliper was frozen so I went to get a replacement and found that these are impossible to get. I bought a 1981 left front caliper and found out that it fits perfect, except the hose fitting thread is different a different thread. So. Eventually I need to replace both front calipers, rotors and hoses. The car is almost 40 years old after all. Can I use a 1981 Caliper which is readily available, if there is a hose that I can replace that will connect to the fender hard fitting and screw into the caliper?

Any other suggestions for these front brakes? I want to get this car on the road and test it first before I really start putting money into it. But its a lifer Oregon car so with the exception of lots of mold, algae, and mud, its solid with no rust. I am also open to any other suggestions for unique Rx 7 things to look at or just replace to get the car reliable. I likely will give this to one of my sons (who also likes old cars) but has no place to work on them as he lives in a city. So I want to go through and change out or inspect any of the usual suspect failure points.

Car has about 118,000 miles on it. Thanks a lot in advance.

diabolical1

iTrader: (3)

Welcome to the board.

Yeah this is a pickle. This thread speaks of a thread adapter: https://www.rx7club.com/1st-generati...ipers-1071051/

Hopefully it helps you out.

Kurzen

Thanks for the tip and I found the adapters. I will call tomorrow to figure out how to get them. But that leads to a question. Why cannot I just change out the caliper hoses with a 1981 version? My thinking is that the hard hose metric brake line fitting on the fender should screw into the female side of the hose. Or does the hard piping from the master cylinder also have its own special brake thread? I also need to replace the brake hoses and don't want to just get an adapter for the older hose if I can just upgrade the hose and caliper to a 1981. Thanks so much. You have been a great help.

shawn1331

It might also be worth looking into a caliper rebuild kit if you would like to try that. I can't promise your original caliper won't be extremely pitted and rusty though.

Kurzen

Thanks Shawn
You will be right regarding the rebuild. I have rebuilt 6 calipers in my life and only one turned out without leaking. This caliper is pretty corroded so I know it is pitted. Mainly because I cannot get out the aluminum piston. One option is to have it re-sleeved in Stainless steel. White Post Restorations does this and I had them do some brake cylinders many years ago for me. Never saw rust or corrosion. However, I am going with the thread adapter route. I Will install this $6.95 item this weekend and update the thread with my findings. If no leaks, Success!

Until then, keep the foot on the gas pedal!

Kurzen

Okay all. I used the BQ41 adapter. This is a Metric 10 1.25 female to 10 1.0 male. Brakequip makes it. I called Brakequip who then connected me to a distributer in California, who then directed me to a distributer in Portland OR, who then got me in touch with Oil Filter Services in downtown Portland OR. This excellent shop specializes in brake and hydraulic lines and particularly in SS braided brake lines. Quite the set up they have and can custom make any auto brake line with SS in 15 min. Anyway, they had the fitting so for $6.99 (no sales tax in OR), I walked away with the adapter. Donated the penny to the penny tray.

I was able to connect my existing 1980 brake hose directly to the fitting (hose is 10 1.25 male), then the fitting into the 1981 Caliper which I got in local stock from O'Reilly's auto parts (10 1.0 female). I had to use two copper gaskets on hose side, and on the caliper side, the male fitting had a flare cut to it and the caliper female hole had also a flare in the bottom. So flare to flare, did not need a copper gasket. The caliper was about $52 with the bracket, which I did non install. But if fit just fine and had the same casting numbers as the old calipers, which are at least 30 yrs old from what I can tell from the maintenance records.

So for clarity, the older 1980 caliper and the new 1981 caliper had the same casting numbers and appeared to be exactly the same dimensions, which the only difference is that the 1980 caliper is threaded with a 10 1.25 female thread for the hose and the 1981 is threaded with a 10 1 thread.

Copper gaskets came from a kit from Harbor freight and one of the sizes in the kit fit perfect.

That's all and thanks for the quick help. Any questions, send them along.