XJ6 & XJ12 Series I, II & III 1968-1992

Spongey Brakes 1985 XJ6

 
  #1  
Old 02-01-2012, 09:18 PM
Junior Member
Thread Starter
Join Date: Mar 2011
Location: Indiana
Posts: 6
Received 0 Likes on 0 Posts
Default Spongey Brakes 1985 XJ6

Hi Everyone, Still a newbie, this is the second XJ6 that I have owned. The car has 68,000 original miles. My XJ6 seems to have spongy brake's it seems you have to pump them to build up more pressure. I am comparing this to my previous car same year, any idea's for me to start with. Thank's so much Sharon
 
  #2  
Old 02-01-2012, 10:07 PM
Veteran Member
Join Date: Mar 2008
Location: Pacific Northwest USA
Posts: 20,151
Received 6,557 Likes on 4,863 Posts
Default

Start with a thorough brake inspection...any obvious defects? .... and brake fluid flush/bleed.

Cheers
DD
 
  #3  
Old 02-02-2012, 12:49 AM
Join Date: Jan 2012
Location: Newport Beach, California
Posts: 3,611
Received 1,149 Likes on 927 Posts
Default Spongey Brakes 1985 XJ6

Originally Posted by sharprrthd View Post
...My XJ6 seems to have spongy brake's it seems you have to pump them to build up more pressure. I am comparing this to my previous car same year, any idea's for me to start with. Thank's so much Sharon
'Spongy' brakes can be caused by a variety of factors, including trapped air in one of the lines, bulging of the flex hoses or a stuck caliper piston. If the fluid appears dark and you don't have the service history of the vehicle, start with replacing all three flex hoses and inspect the brake discs for even wear. If uneven wear is evident, especially in the rear, a seized piston or stuck pads may be the cause of the poor pedal feel.

The rear brakes on the XJ6 are often overlooked due to the cost of servicing the calipers and discs. The design is directly from a racing car with inboard discs and calipers to reduce unsprung weight and add to the car's excellent handling characteristics, but to service the rear brakes for anything other than bleeding or pad replacement requires removal of the entire rear suspension assembly complete with differential. If new discs are required, they must be centered within the caliper by placing shims in front of or behind the disc prior to reattaching the universal joints.

NBCat
 
  #4  
Old 04-14-2012, 11:53 PM
AristoCat's Avatar
Senior Member
Join Date: Sep 2010
Location: Portland, Oregon
Posts: 220
Received 27 Likes on 22 Posts
Default

Just rebuilt the front calipers on teh SIII XJ6 (6 of the 8 pistons were stuck)

been going back & forth bleeding the Passenger's & Driver's side calipers, but the brakes still feel a little squishy.

I'm not getting air bubles from the calipers anymore, so I'm starting to wonder if there is a relief valve somewhere else in the system.

also, I'm still using the OEM brake lines, which dont seem to be buldging, but I plan on replacing them with a set of Teflon/ braided stainless steel/ JIC hoses.

I just dont want to start digging through the engine bay on a hunch that there is a relief valve, that may actually not exist, meanwile accidently causing damage to the frail, but operational wiring system. (soon to be replaced, stay tuned.)
 
  #5  
Old 04-15-2012, 08:24 AM
Senior Member
Join Date: Jul 2010
Location: Bullhead City, AZ
Posts: 194
Likes: 0
Received 18 Likes on 15 Posts
Default

I had a similar problem that was due to a stuck caliper on the rear brakes. The fluid would heat up and the brakes would feel spongy. When the fluid cooled off the brakes would be fine. Had to do a full brake job on the rears to cure the problem. I will say that although the rear brakes are a real tough job, it is a DIY project with the right tools and a helper. Took me about 10-12 hrs to do it and that was my first time.
 
  #6  
Old 04-15-2012, 11:37 AM
AristoCat's Avatar
Senior Member
Join Date: Sep 2010
Location: Portland, Oregon
Posts: 220
Received 27 Likes on 22 Posts
Default

On to the rear brakes then!
 
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Jefro
New Member Area - Intro a MUST
11
09-15-2015 01:44 PM
Charlene n John
XJ6 & XJ12 Series I, II & III
2
09-14-2015 12:01 AM
Steve10
XJ6 & XJ12 Series I, II & III
2
09-09-2015 07:54 PM
rusty37
XJ6 & XJ12 Series I, II & III
5
09-08-2015 06:16 PM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 

Thread Tools
Search this Thread
Quick Reply: Spongey Brakes 1985 XJ6


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: