Bleeding Brakes

I haven't bleed the brakes for a number of years. The last time was on a 1972 triumph spitfire which did not have power assisted breakes.

Here it the method I used back then:

1) start from the farest wheel cylinder and work to the closest. 2) using a clear tubing connect the tube from the nipple to a clear jar

with brake fluid in it.

3) pump the pedal and hold, open the brake nipple. 4) continue until there are no air bubbles coming out. 5) make sure to replenish the brake fluid in the master cylinder as fluid exist the wheel cylinder. 6) repeat 3), 4), and 5) on the other wheel cylinders.

Is this the correct method for assisted and non-assisted brakes?

Mike

Reply to
mike
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Good.

Good.

I open the nipple and then have an assistant slowly pump the pedal unitl there are no more bubbles coming out.

Good.

With the exception noted, yes it is the same.

-------------- Alex

Reply to
Alex Rodriguez

Key tips:

If you have fully drained the MC for whatever reason, you may need to bleed the MC first. Look to see if the MC outlet port is at the highest part of the MC, if it is it should self bleed.

Pump the pedal slowly, if you pump too quickly you may create bubbles from cavitation.

If you have a partner, the final few pumps on each corner can be done by stroking the pedal to the floor with the bleed screw open, closing the bleed screw, raising the pedal, repeat.

Brian

Reply to
Brian

Lastly, there is a school of thought that actuating the brake pedal beyond it's point of travel will eat the seals in the MC. I can understand why someone would think this and it sounds reasonable, however, I've never had a problem with it and I've bled a lot of brakes in my lifetime. Of course, this also assumes that the leak is big enough that someone would notice it.

-Bruce

Reply to
Bruce Chang

Super,

Thanks for all that feedback.

Mike

Reply to
mike

That method will generally work for most brakes. Like Bruce, I have never damaged brake parts by doing it this way.

It will NOT work for Teves type systems (which, thank God, are rare)

Reply to
<HLS

Yes, unless the owner's manual specifies otherwise. To get the absolute firmest pedal, have a helper pump the brake pedal a few times and close the bleeder screw before your helper releases the brake pedal, then reopen when they depress it - just for the last few cycles.

Alternately, get a pressure bleeder. I can't figure out how I lived without mine. Motive Products makes a cheap but useful one.

nate

Reply to
N8N

That's the way I've always done it. I have discovered that some manufacturers specify a different bleeding sequence. I don't know why but I've seen it in print. Might be worth a look. FWIW YMMV

Reply to
NickySantoro

The jar-and-tubing method requires more coordination, and/or more pushups and situps, than I can muster. I use a handheld vacuum pump called the Mityvac

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It comes with a nicebooklet describing other diagnostic and repair procedures you can dowith the thing.

I also like to use it to carefully remove any sediment from the bottom of the master-cylinder reservoir before beginning, rather than suck that crud down through the rest of the system.

Some authorities differ on the order in which you address the different wheels, depending perhaps on the car and whether its brakes are split front-rear or diagonally.

The concerns about bleeding the master cylinder if you've emptied or replaced it, and replenishing its fluid often enough to avoid running it dry (in which case you have to bleed it and start over) are still applicable of course.

I don't think this varies between assisted and non-assisted brakes. If you have antilock brakes, though, refer to the shop manual for any different or additional procedures.

You're supposed to capture the used brake fluid and take it down to the local household hazmat facilities, rather than dumping it or mixing it with recyclable chemicals. It's supposed to be contaminated with heavy metals, making it less innocuous in detailed reality than its basic chemistry might lead you to believe.

Wear rubber gloves, and as with any undercar work, wear safety glasses. Also, move carefully and deploy old rags strategically so as to avoid getting either new or old brake fluid on your paint job -- especially lacquers!

Cheers,

--Joe

Reply to
Ad absurdum per aspera

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