Bleeing the brakes 1973 240Z (?)

[este]

Hello, Im a new Z (1973Z ) owner

While driving it home I had the rear brake line snap, soI decided to have it towed home + the front brakes were a bit sketchy for freeway traffic, Im guessig this is because the car was stagnant for a bit over a year I was told (feels more like 2) and had not been started in at lest 6 months-1 year.

Well I got home home and the tried to bleed to brakes to see if the system worked. there was almost no fluid coming out of the purge valve and the brakes had no resistance whatsoever. I fugured it had to be the master cylinder was shot so I got lucky and found a OEM replacement (rebuilt)

I installed it, and attempted to bleed the system again, after a while and lots of pedal pumping the amount of fluid pumped out looks/feels right.

I also bled the maste cylinder as the instructions required it so.

Still im not getting much breaking, the car brakes but not too good I think.

Should I bleed the rear brakes? can I bleed the rear drum brakes? the instructions recomend bleeding the rear brakes but I couldnt find the purge valve? or should I just re-bleed the master cylinder and call it a day and take the car to a shop?

I want to learn to do most of the work myself, not to save $$ but to use it as a learning experience.

thanks

Esteban

[kmack]

este,

If you had a brake line "snap", you really need to take a look at all the other lines also. On a '73, the old rubber lines will be rather...old. Replace them. You've already replaced the master cylinder, might as well relace the rubber lines, too.

If this is not your primary mode of transport, I'd also take the time and rebuild/replace the rear cylinders. You might have to rebuild them because new cylinders for the early cars are getting in short supply. It's easy to do and not much is involved.

Rebuilt front calipers are pretty cheap to get. I think about $35-40 each at Autozone and the like. Pick up at least a Haynes manual for the car, too.

As for bleeding the system, the bleed nipples for the rear are located on the rear cylinders right next to where the hard metal lines connect to the cylinder. You'll have to look on the back of the wheel. If they are not there, then they may have been broken off by the previous owner and you'll have to replace the cylinder.

Either buy or try to find someone that has a pressure bleeder. It is by far the easiest and surest way to get all the air out of the brake lines. Not to mention you'll be able to do the work completely by yourself. Makes changing brake fluid easier too. Pressure bleeders will run about $45-55. Do a search on the net for Motive Products.

Something else to consider (as I'm having this issue at the moment), if you hear the sound of air rushing out from under the dash while you are applying the brakes, you'll also need to check out the brake booster. If the booster is bad, you can still drive the car, but it's much harder to brake (takes more foot pressure).

Hope this helps.

[Bambikiller240]

Replace bleed nipples with Speed Bleeders

http://www.classiczcars.com/forums/showthread.php?t=9046&highlight=Speed+Bleeders

http://www.speedbleeder.com/

[JLPurcell]

If can't find or do not want to invest in a power bleeder and have to bleed the brakes yourself try this:

Bleed one wheel at a time, put a rubberline on the bleeder, (tight fit) put the line into a bottle of brake fluid (make sure the line is submerged in the fluid) and open the bleeder. Pump the brakes a few times then move to the next wheel until all four corners are complete (make sure master cylinder resevoir does not run dry). If the pedal is still soft start over. Start on the rear brakes.JLP

[kmack]

Replace bleed nipples with Speed Bleeders

Not to rain on your parade, Carl, but I've heard some bad things about the speed bleeders. Some of it being longevity issues with the life of the product, not to mention they don't always get the right product in the right packaging.

The biggest reason I like using a power bleeder is you never have to get in or out of the car to push the pedal. That saves a lot of time. I can flush the entire system on my 240 in less time than it takes to jack up the car! Usually less than 15 minutes. And as tight as my garage is at times, not having to get in or out of the car is a big thing in my book. Well worth the money spent for the time saved.

Also, the power bleeder can be used on other vehicles without much involvement.

[chickenwafer]

right with you kmack- I heard some bad stuff about speed bleeders as well, although I have heard some good stuff too. A power bleeder seems like the best bet here- if you know what you are doing it takes almost no time.

Dave

[Bambikiller240]

Well, I have actually HAD them on my car for 4 years now and mine have worked and still work just fine. Don't beleive everything you "hear". I, too can bleed my brakes in less than 15 minutes.

Now, nobody get all huffy and think I'm pointing a finger at anyone specific, but.........

The only problems I have ever heard are from HAM FISTED mechanics who overtighten them and snap them off. But if the mechanic has common sense enough to realize they are BRASS and uses due care to not overtighten them , they work great.

FWIW, I have "heard" that Power Bleeders don't always fit every application properly.

[este]

hm.. Well that was one of my problems, I dont necessaily have anyone to help me, my schedule seriously contradicts everyone of my firends so I may just need to find a way to do this myself. I will def. look into the power bleeders as it seems it may work best for me.

KMACK:

Whenever I first tried to bleed the brakes the was a "gurgling sound coming from what I thought was the master cylinder, I basically thought the seals in the master cylinder had dry-rotted is this the issue youre talking about?

Also when I pulled the master cylinder the rod was pushed all the way in! isnt the cilinder supposed to be depressed?

Im sure the booster hasnt been replaced before it looks pretty old so how much should this set me back? and how hard is it to replace it?

thanks!

Esteban

[kmack]

Este,

That gurgling sound was most likely the master cylinder. As for the rod being pushed in, there is a spring in the MC that is supposed to push the cylinder back out some. So staying pushed in is not a good thing.

On the booster side, outside appearence does not necessarily mean it's bad. Mine looks terrible on the outside. But only recently starting acting up. I have a slight "rushing air" sound coming from underneath the dash while depressing the brake pedal. My idle speed will also increase at the same time. It's due to a vacuum leak cause by the malfunctioning booster. It's not hard to replace the booster. Only hard part is getting at the 4 nuts up under the dash to get it off the firewall. You have to be somewhat of a contortionist. Not bad, but definitely not the most comfortable thing in the world.

Where are you located in Texas?

[kmack]

FWIW, I have "heard" that Power Bleeders don't always fit every application properly.

Well, Carl,

Having never used Speed Bleeders, I can only recount what I heard from others that have. There was a long discussion about them a few years ago on the email list. That is my basis of information.

But I have personally used the power bleeder on every vehicle I own and a few others I don't. Yes, they do not have vehicle specific reservoir caps for the bleeder. They have adapters that will fit multiple vehicles. I think they have like 3 or 4 adapters (at least 3 for sure). I have all three. I have used all three and as long as you keep them tight, never will a drop of brake fluid be spilt. Haven't had a spill in two years.

As for my opinion, I prefer not to have to get in the seat, pump the pedal, then get out and get under the car time after time for each wheel. Plus with the power bleeder you can actually see when the air bubbles stop running. With the speed bleeders, unless you have another person, I don't see how you can pump the pedal and watch the fluid for air bubbles at the same time. Not quite as accurate in my book. But then I race my car, so it's more of an issue.

[este]

Ding sing sing its the booster.

I forgot to mention that my idle is affected everytime the brakes are pressed.

Well im hoping it doenst rain today since Im stripping the intrior trying to find the rust...

[Bambikiller240]

As for my opinion, I prefer not to have to get in the seat, pump the pedal, then get out and get under the car time after time for each wheel. Plus with the power bleeder you can actually see when the air bubbles stop running. With the speed bleeders, unless you have another person, I don't see how you can pump the pedal and watch the fluid for air bubbles at the same time. Not quite as accurate in my book. But then I race my car, so it's more of an issue.

I simply put a clear hose on the speed bleeder, put the hose in a tall bottle. Loosen the speed bleeder, slide on my creeper over to the open drivers door and reach in with my hand to pump the brake pedal while looking under the car at the bottle. When I don't see bubbles, I slide back to the bottle, tighten the speed bleeder and move to the next corner of the car. I never get in the car, I just reach in with my hand.

Actually, proper brakes when driving on the street should be at least as important, given the liability issues added to the issue of your (and any passengers) safety.