Brake disc temperatures - AUSJEEPOFFROAD.COM Jeep News Australia and New Zealand

Murchison Products
Find out how to advertise on Ausjeep?

Go Back   AUSJEEPOFFROAD.COM Jeep News Australia and New Zealand > JEEP GARAGE > ZJ WJ WG Grand Cherokee


Portal Register Forums Trading Your Jeep New Garage Mark All Read

Post New Thread  Reply
 
Thread Tools Search this Thread
  #1  
Old 2 Weeks Ago
Jensjohnson  Jensjohnson is offline
I just registered
 
Join Date: Sep 2018
Posts: 19
What Jeep do I drive?: WG
Likes: 0
Liked 1 Time in 1 Post
Default Brake disc temperatures

I have a strange issue with my rear brakes: All new calipers, and rear outer hoses. New slide pins, calipers slide easily. But if I drive a ,say 20 km driv, without touching the brakes at all, the discs are qiute hot. I cantouch them, but its just barely. Its like a hot cup of coffey. Front discs are ice cold. When i jack up the car, its no problem to spin the rear wheels, so it doesnt really stick. No smoke either.
I have changed the fluid. The car rolls eaasily when in Neutral. Is this normal? Can it be the source of my bad fuel consumption?
  #2  
Old 2 Weeks Ago
JeanLuke  JeanLuke is offline
Full Flexer
 
Join Date: Jul 2017
Location: SE Qld
Posts: 647
What Jeep do I drive?: WG
Likes: 88
Liked 119 Times in 92 Posts
Check out my Ride(s)
Default

Disc brakes rely on a little run-out of the disc to push the pads back. They have no spring returns. The WJ front discs work hard normally, so they are more likely to have a little more run-out than the rear.

From what you posted, I don't see any problem. If the drag was enough to burn an extra few litres per 100km then after 20km they'd be glowing red.
Sponsored Posts
  #3  
Old 2 Weeks Ago
Jensjohnson  Jensjohnson is offline
I just registered
 
Join Date: Sep 2018
Posts: 19
What Jeep do I drive?: WG
Likes: 0
Liked 1 Time in 1 Post
Default

I found some receipts in the car , one of them telling me that the master cylinder was replaced 3 years ago. I have read on several forums that a mismatching pushrod lenght can be an issue, if the brake booster was not changed at the same time, and the brake booster seems to be the original one.
Is this pushrod adjustable? Maybe the master cylinder has a little bit of pressure applied to it even if the pedal is released... ?
  #4  
Old 2 Weeks Ago
Jensjohnson  Jensjohnson is offline
I just registered
 
Join Date: Sep 2018
Posts: 19
What Jeep do I drive?: WG
Likes: 0
Liked 1 Time in 1 Post
Default

Is this pushrod adjustable, or can I simple take it out and cut of one millimeter at a time to get this fixed? Im almost sure this must be the problem, the brakes start to take when I touch the pedal with my foot. There is no dead spot at all
Sponsored Posts
  #5  
Old 2 Weeks Ago
layback40's Avatar
layback40  layback40 is offline
Grumpy Old XJ Dsl Owner
 
Join Date: Jan 2011
Location: Northern Victoria
Posts: 13,471
What Jeep do I drive?: XJ
Likes: 3,695
Liked 6,107 Times in 4,038 Posts
Default

Quote:
Originally Posted by Jensjohnson View Post
Is this pushrod adjustable, or can I simple take it out and cut of one millimeter at a time to get this fixed? Im almost sure this must be the problem, the brakes start to take when I touch the pedal with my foot. There is no dead spot at all
Rather than starting trial mods that are permanent, why not try a short trip some place safe with the vac line to the booster disconnected? You will need to clamp the tube & be careful if you remove it from the booster so as not to break the plastic fitting. The next would be to place washers between the booster & the firewall on the mounting bolts, this will have the same effect as a shorter rod. You can cut a piece out of the washer so it can be put in without removing the booster.
__________________
98&01XJ VMs,06 KJCRD,I no longer question authority,I annoy it.More effect,less effort.10000Club
  #6  
Old 2 Weeks Ago
JeanLuke  JeanLuke is offline
Full Flexer
 
Join Date: Jul 2017
Location: SE Qld
Posts: 647
What Jeep do I drive?: WG
Likes: 88
Liked 119 Times in 92 Posts
Check out my Ride(s)
Default

Quote:
Originally Posted by layback40 View Post
Rather than starting trial mods that are permanent, why not try a short trip some place safe with the vac line to the booster disconnected?
I could think of many reasons why not, top two on the list being no effective brakes and possibly no insurance coverage if things end badly.
Sponsored Posts
  #7  
Old 2 Weeks Ago
Jensjohnson  Jensjohnson is offline
I just registered
 
Join Date: Sep 2018
Posts: 19
What Jeep do I drive?: WG
Likes: 0
Liked 1 Time in 1 Post
Default

Quote:
Originally Posted by layback40 View Post
Rather than starting trial mods that are permanent, why not try a short trip some place safe with the vac line to the booster disconnected? You will need to clamp the tube & be careful if you remove it from the booster so as not to break the plastic fitting. The next would be to place washers between the booster & the firewall on the mounting bolts, this will have the same effect as a shorter rod. You can cut a piece out of the washer so it can be put in without removing the booster.

Yeah, I actually tried this, and without the vacuum it was dragging less, almost no heat at all. But its not easy to get to the backside of the booster?Very tight space back there, but I will try.
  #8  
Old 2 Weeks Ago
Jensjohnson  Jensjohnson is offline
I just registered
 
Join Date: Sep 2018
Posts: 19
What Jeep do I drive?: WG
Likes: 0
Liked 1 Time in 1 Post
Default

Is it not possible to shim between the master cylinder and the booster? Much easier access.
  #9  
Old 2 Weeks Ago
Nanook's Avatar
Nanook  Nanook is offline
AJOR Bronze
 
Join Date: Mar 2014
Location: Lake Macquarie, NSW.
Age: 49
Posts: 2,236
What Jeep do I drive?: JK
Likes: 574
Liked 850 Times in 595 Posts
Default

How many Kms on your vehicle? If your wheel bearings are about to let go, it would cause a lot of heat to the rears.

Also, has your parking brake been adjusted too tightly and dragging? That would account for the heat and bad fuel economy.
__________________
Cheers,
Jamie
Post New Thread  Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


» Advertisements_AS2


Powered by vBadvanced CMPS v3.2.3



All times are GMT +10. The time now is 05:54 AM.




AJOR does not vouch for or warrant the accuracy, completeness or usefulness of any message, and are not responsible for the contents of any message. The messages express the views of the author of the message, not necessarily the views of AJOR or any entity associated with AJOR, nor should any advice be substituted as technical advice replacing that of a mechanic. You agree, through your use of this service, that you will not use AJOR to post any material which is knowingly false and/or defamatory, inaccurate, abusive, vulgar, hateful, harassing, obscene, profane, sexually oriented, threatening, invasive of a person's privacy, religious, political or otherwise violative of any law. You agree not to post any copyrighted material unless the copyright is owned by you or by AJOR. The owner, administrators and moderators of AJOR reserve the right to delete any message or members for any or no reason whatsoever. You remain solely responsible for the content of your messages, and you agree to indemnify and hold harmless AJOR, the administrators, moderators, and their agents with respect to any claim based upon transmission of your message(s). The use of profile signatures to intentionally mislead or misdirect any member on this forum is not acceptable and may result in your account being suspended. Any trip that is organised through the AJOR forum is participated at your own risk. If you or your vehicle is damaged it is your responsibility, not that of the person that posted the thread, message or topic initiating the trip, nor the organisers of AJOR or moderators of any specific forum. This forum and associated website is the property of AJOR.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2019, vBulletin Solutions, Inc.

AJOR 2002 - 2019 AUSJEEPOFFROAD.COM. All corporate trademarked names and logos are property of their respective owners. Ausjeepoffroad is in no way associated with DaimlerChrysler Corporation or Fiat Jeep.
www.ausjeep.com www.ausjeep.com.au www.midlifemate.com ausjeepforum.com Jeep Wrangler JL Australia release
vB Ad Management by =RedTyger=