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1997 Volkswagen Jetta Repair Question


Topics covered: Piston, Brake pads, Brake pedal.
Mileage: 140,000 miles.

Asked on October 17, 2012

Volkswagen Jetta Piston Problem

I just replaced both rear calipers, bleed the lines, but can not get brake pedal to not go directly to floor.
After replacing the first caliper I was able to regain brake pressure. I have not replaced the emergency brake cables yet.
Avatar Asked by (pending member)

Answer

Replied on October 17, 2012

Did the new calipers come with new brake pads?

When you installed the caliper/pads onto the rotor, how much "free play" was there between the pads and the rotor?

Thomas

Tiny Answered by exovcds
0 questions asked
Replied on October 17, 2012

I just uploaded a video showing "free play" on a Mk5 Jetta... although the caliper/pad design is different, the principal still applies:

http://www.youtube.com/watch?v=_vNj-UOHW-8

If your caliper piston was retracted all the way when you installed it... then there would have been over 1/4" of free play, that the
piston has to travel the "first time" you applied the brakes. What that does, is cause the ratchet in the piston to not work correctly
and that will cause "low pedal" issues.

What you need to to is turn the piston back in all the way and then turn it out manually until you have a little bit of free-play when
the caliper is sitting over the pads...2mm or so.

Then, pump the pedal and and re-bleed.

Thomas

Tiny Answered by exovcds
0 questions asked