Brake line/ caliper problem

[kennzo5150]

O. So I rebuilt my calipers, now I have a problem. But I think the problem was present last year. All my calipers are getting juice except one. I took it off checked too see if lines/ calipers were plugged nope. So what is the problem? How do I fix it?

Which one doesn't get the juice? I guess it's in the (left) rear? Remember that the rear calipers have two bleeding screws on each side.

A mistake made quite easily is changing the left and right caliper. The bleeding screw(s) should be located at the top. In the reversed situation both calipers are impossible to bleed.

Check and check again.

Otto

[kennzo5150]

Aha ! Yes Otto it is the left rear!!!! I am pretty sure I didn't mix them up . But I did put the bleeders on the bottom. Doh!!!!! The brake pedal goes too the floor, doesn't return and have no brakes. Thanks for the heads up Otto...

[kennzo5150]

So let me get this straight. The rear calipers are side specific? Right only goes on right side and left, left? You can't have them the other way at all? I think I put them on the right way, I even wrote on the inside of caliper with a sharpie which side was which. But the old owner may have buggered around with the brakes. I will experiment.

The rear bleeders are situated at the top. The short tubing between the left and right half of the caliper is at the bottom.

What procedure did you use for bleeding? Which order and what equipment or a helper. I had bad experience with one of these vacuum bleeders. For me it works best to put a helper in the car at the brake pedal (remember the pedal needs 2 mm play), open the bleeder a half turn, push the brake pedal as fas as possible, close the bleeder, release the pedal. Repeat this procedure until all the air left the system.

The (German) factory manual recommends the next order of bleeding:

Left rear, outside bleeder
Left rear, inside bleeder
Right rear, outside bleeder
Right rear, inside bleeder
Right front
Left front

Keep posting, we will get the air out of the system!

Otto

[kennzo5150]

Otto , the way you describe too bleed the brakes is that right? I took everything apart, put it all together the right way. Still no juice too the rear caliper. And when I bleed like you told me the fluid rises in the reservoir. This is taking forever, I even tried a vacuum pump, those are junk. Thinking about rippin everything off and adding Teflon wrap too everything. I don't know , I don't have any fluid leaks. The pedal gets pressure and the reservoir goes down. I am doing this by myself . I just put a dumbbell on the brake pedal.

[Jcslocum]

No Teflon on brake fittings....EVER!!!

You need 2 to really bleed they system manually.

Indeed, never use teflon on the fixings. You dont't need it, is basically wrong nd could be dangerous.

Yes, I use the described method and it works not only for me.

That the fluid returns to the reservoir meabs that something is wrong. Did you appply the 2 mm play between brake pedal and the MBC rod? No play also can cause unexpected reactions in the system. Check it. The brake fluid only returns after releasing the brake pedal, not when you press it.

Remember, with standard factory recommended parts and products, correctly installed and adjusted, your brake system can be better than a lot of modern cars.

If the pedal play is correct, I would check the MBC again. Take it apart to make sure you assembled everything in the correct way.

Otto

[kennzo5150]

Well I found a problem, the left rest hose had a hole. I also think it collapsed internally. So I changed the 2 rear hose too steel braided. I bled all the calipers, and took it for a little drive. Don't worry live no where near anyone. Brakes didn't work, so I am suspecting the master cylinder is shot . Kinda has a sucking sound when I pump the brakes. So anyone know where I can get a rebuild kit ? Or has anyone put in a dual master? Using a dual master is there any modding? Or is it drop in and go?

I thought you also had rebuild the master brake cilinder. You are talking about installing a "dual master", which means that you have pre-'68 912 with a single circuit. Basically changing to a dual circuit - which is much safer, in cae you would drive somewhere you could meet people, cars or animals - is not difficult. I did it for my '65 because of the mentioned safety reasons. Nevertheless a single circuit should work fine.

Apart from the dual MBC you will need a different (dual) reservoir, some additional flexible lines and L-connector for the fixed brake lines. I would say: spend these few hundred dollars for your own and other peoples safety. Buy a new or rebuild a used MBC.

BTW, I don't like these braided lines, because cracks in a standard rubber line can be seen, but it's hard to check what the condition of the inner rubber of a braiaded line is.

If you need more info, just let me know.

Otto

Otto

[JT912]

Dual MC will also require a different pedal cluster that has the mount for the brake light switch.

[kennzo5150]

Well I think I have too order a master cylinder today . I am positive that is the culprit. I am unemployed so I was trying too keep the cost down. Otto my car is pre-68 , it is a 66 . Maybe just maybe it will be road worthy next week (sigh) .

[kennzo5150]

I will go too the single curcuit for the time being .

I understand that you want to keep it low budget. Try to get a rebuild kit. I'm not sure if they are still available.

Otto

[kennzo5150]

Alright , so I changed the master cylinder. I did't bench bleed it. Like I've said I'm a total novice when it comes too brakes. But I did bleed the master many, many times. And I've bled the brakes many, many times. I still have a mushy pedal on the 1st pump, comes up stiff on the 3 rd pump. What could be the problem? I haven't adjusted the pedal yet . Dont know what to look for, do I move it in till it bottoms out then back it off. God this is drivin me nuts, trust me I'm really not stupid , but I'm stumped.

[kennzo5150]

Aha ! I think the culprit is the brake pedal rod. I think it is out of adjustment. If I move it in I get the pressure I need , but pedal is slow to return to foot . If I move the rod the other way, not as much pressure but quick too move back . So how do I measure the distance I need?

[Rick Becker]

Have you replaced the pedal bushings? The old plastic ones were known to swell up / wear out and stick. Upgrade kits using bronze bushings for the entire pedal assembly were developed to solve this.

[kennzo5150]

Rick , I think you may be right. I might have too go that route . I can't figure out what is wrong , but I think that is it . Crappy waiting 3 weeks for parts though. Where I live the driving season is fast coming to an end.