Who has to pump their brakes?

[Guest Anonymous]

I know if i want to stop quickly, i have to pump my brake pedal once. Drove another Z and it was the same exact way. is this just a common z problem?

[Tim240z]

I had the same problems. Replaced the master (twice, once with a reman. which lasted just over it's 1yr warranty period, and then a NEW one). That still didn't really solve the problem. I replaced the shoes with new ones, which I don't think was really necessary. Then I swapped the rear slave cylinders with the ones from my Hybrid (went to rear disks). That has solved the problem. Even though the originals ones didn't appear to be leaking, they must have been pulling in air, 'cause I would have to bleed the rears every 100 miles or so.

Tim

[Miles]

I was having the same problem with my son's 72 240Z V8. So I replaced the master cylinder, rear wheel cylinders, rear shoes etc with new original Nissan parts. I have bled the brakes, including a power beed, five or six times and finally got all of the air out this morning. Proper shoe adjustment helped stiffen up the pedal. If you replace the MC be sure to bench bleed it.

 

Check for leaks at all of the hard line unions including the connections to the MC. I sprayed brake cleaner on all of the unions I could reach and wiped them clean. Pumped the brakes a few times and sure enough there were some unions leaking brake fluid. Hit the leaking unions with a 10mm tubing wrench and all is well.

 

Miles

[Guest Anonymous]

My old silver Z if not constantly using the brakes would lose pressure in the master cylinder . The pressure would hold for about 10 minutes without any brake use and after that a few pumps would bring the pressure back to normal. I switched to a used master cylinder that keeps up the pressure for all occasions. It is hard all the time now !

[Mike C]

Switch to semi-metallic pads in the front and cast iron drums in the rear and you will notice a big improvement in fade resistance. Isn't it amazing how rear shoe clearance affects pedal firmness in an early Z?

[fl327]

semi metallics are good for the street i think, no pumping to stop here unless i lock em up, i dont knwo im just a weirdo, i think my car stops really good with my ghetto 4x4/metalmaster, and stock(but new) alum drums with new stock shoes and that zx mc, its a street car, so i dont have to repeatedly stomp em out all the time either though. i do have some ss lines i havent put on the car yet because it was such as pain in the ass to get the mc in, but im keeping them around for a future install.

[Guest Anonymous]

That's funny Len, I have some SS lines I haven't installed cuz I'd have to bleed the brakes again.

You lazy BasTa*d!

 

Jon

[Guest Anonymous]

Oh, I have a bone stock 72 braking system. I dont have to pump. Just push real hard when things get scary.

 

Jon

[Guest Anonymous]

I adjusted my rear shoes and now it feels incredilble. A lot less pedal travel and effort to brake. It still has MAJOR brake fade problems though, i guess thats a big downfall w/ the z brakes

[jeromio]

I thought I would add some hard-won wisdom to this thread. I replaced a caliper yesterday and absolutely could not bleed down the system.

 

One factor that may be important is that in the process of bleeding, I let the front reservoir (rear brakes) run dry (my son was helping me, so, umm, err, it was his fault, yeah, right, that's it). Anyway, I bled and bled and bled. Many hours of foolishness.

 

Now, keep in mind the MC was not replaced, nor were any lines. I did go thru and check/tighten them cuz I was desperate. But here's what ended up fixing the problem: I bled the M/C. Here's the other interesting bit, the front bleeder (rear brakes) was clean - no air. But the rear bleeder (front brakes), blew lots. Lots and lots and lots of air.

 

So, there ya go. When in doubt, pump it out. Okay, that doesn't mean anything, but it does rhyme.

[katman]

Most of the time long pedal travel is rear shoes out of adjustment. On our ITS cars we retain the parking brake so that during the course of a race we can pull it up a notch to take up some of the wear and retain a high pedal. It's also possible to taper the front pads and rotors such that there's a lot of slack to take up there too. So basically keep everything trued, adjusted, and properly bled.

 

Fade isn't a problem unless you have pads that aren't up to the job you're requesting. If you're racing with stock calipers and drums (like in ITS) then you need some cooling ducts too, but if you're fading on the street it's probably a cheap pad.

[Pop N Wood]

My 70 240 would occasionally feel like the pedal was bottoming out on hard stops. Scary. I replaced the stock MC with a larger diameter model from a 280 to solve the problem.