Question about 1988 Jeep Comanche

1 Answer

1988 jeep comanche brake proportioning valve

Rear brakes get lock when I press brake pedal.i'm pretty sute tha it is the proportioning valve.I want to know if ther is a way to solve it the problem

Posted by on

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • Jeep Master
  • 20,706 Answers

There only 2 ways (USA answers)
they have a guage test (expensive gauge)
or replace it ,if in fact you know for sure the rear brakes are good.

i think raybestos sells this.valve rebuilt.

the valve is height measuring disconnect the link and see if its
free? is it jammed? i had a 88 from new.
i purged brake fluid every year and it lasted for 250k miles. and sold it.
so there is a bench mark on life.(best case)
did you read the fsm? yet
id does cover these tests.

try alldata.com (usa ) it may cover Commanche.

Posted on Feb 17, 2014

  • _-__-___-_
    _-__-___-_ May 09, 2014

    louis, what speed, 1mph , 70? what road conditions as all non ABS cars can be forced to skid. (lock) . wish i could drive it and inspect it first.

×

5 Suggested Answers

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

Mikey108
  • 475 Answers

SOURCE: Break Lights won't come on in my 1988 Jeep Comanche

Why replace the whole fuse box? That's rediculous. If you can't find the fuse box, just fix the affected circuit. Did they check the brake switch?

Posted on Nov 25, 2008

Mikey108
  • 475 Answers

SOURCE: 99 Jeep GC brake lock.

You say they replaced basicly everything that involes the rear brakes.
Every step they took to find the problem could lead to the solution,BUT did they check the inboard brakes. The brake system on a jeep that has rear rotors have inboard shoes for the parking brake.
You could have a parking brake cable that is frozen (this will cause a drag on the inboard brakes. Do you use the parking brake? Maybe the parking brake shoes are adjusted too tight?

Posted on Feb 10, 2009

  • 550 Answers

SOURCE: What does the EGR valve look like and where is it

GOOGLE found THIS.
GL, Td

Posted on Apr 08, 2010

  • 9 Answers

SOURCE: 1999 jeep grand cherokee brake light

Don't know if this will help but its how i fixed my 2001. Go to: http://www.2carpros.com/forum/2001-jeep-grand-cherokee-laredo-brake-lights-not-working-vt4814.html Tip: If you have a small piece of medal to put under the ground contact point then it will keep it raised in place, i used a really big staple from a staple gun to slide under mine I also replaced all the sockets that the bulbs go into cause mine were falling apart and may have been a part of the problem.

Posted on Apr 20, 2010

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

The front drivers side break keeps locking. I have replaced the caliper and now when I pump it no fluid is coming out from the line.


Did air get into the master cylinder? If you can, try bleeding the master cylinder. The fact that you aren't getting any fluid out of the line suggests that the master cylinder isn't pumping fluid.

Master cylinders are (usually) on a split circuit system - that is, the front left brake is on the same line as the rear right. The front right brake is on the same circuit as the rear left.

A point to be aware of is when bleeding brakes/doing brake work and if the master cylinder runs dry, is that a seal inside the master cylinder can fail/twist over and not pressurise that particular line, even though it may pressurise the opposite brake line.

I'm in the UK. I have a 1998 Jeep Grand Cherokee 4 litre, which I am slowly rebuilding. Three weeks ago I fitted new front brake rotors, new front callipers and pads. I've been rebuilding cars for over 40 years now and have done countless brake overhauls.

.. and could I get a hard pedal after the job was completed? I must have bled the brakes three times a day for a week and couldn't get a brake pedal. I phoned a full time mechanic I know - he came and tried to bleed the brakes three times and couldn't get a hard pedal.

That's when you think 'The master cylinder was working before I started the job so it must be still working now'.

I fitted a brand new master cylinder and because some parts for older jeeps are hard to come by in the UK, I fitted a second hand proportioning valve. When I bled the brakes again the pedal became rock solid. Fixed.

You're probably fed up with your braking problem now ... and apparently this 'no fluid/brake pedal' is more common than you may think.

Try bleeding the master cylinder if you can. If you suspect that it isn't fully working - try an overhaul kit which is cheaper than a new master cylinder.

As for changing the proportioning valve .. that's your decision. My brakes now work though the truth is I don't actually know which was at fault as I changed both the master cylinder and proportioning valve at the same time. Maybe both were at fault, for whatever reason. I genuinely don't know.

The positive aspect is that you are doing your own work and know what you're doing. You're saving on labour charges.

Apr 18, 2016 | 1998 Dodge Grand Caravan

1 Answer

What does the proportioning valve do?


Assuming you're talking about the brake system...
The proportioning valve is on the rear brakes only when the vehicle has rear Drum Brakes.
What it does is limits the brake line pressure to the rear brakes during normal stopping. This way the rear brakes don't lock up and cause the vehicle to fish tail or spin.
When you press the brakes harder than normal, the proportioning valve opens more to allow more line pressure so you're able to stop faster.

Jul 10, 2014 | 1983 Jeep CJ7

1 Answer

Fleetwood problem


Pretty normal to not be able to lock the brakes without the assistance of the booster, it'll take a lot of pedal pressure without it. It's also normal for the pedal to feel harder without the booster, this goes for any car/truck with power brakes. Try it with any other car you have and you'll see.

I've worked on several old Cadis but don't recall what year they started using front disc. If it's been changed from drum to disc you'll likely need a different proportioning valve and possibly a different master to get them to work right. Talk to the seller and ask if the brake feel changed when they replaced the master and if they changed any other parts.

Mar 31, 2017 | 1968 Cadillac Brougham

1 Answer

Proportioning valve.


get it serviced now, its dangerous to drive
old post

Feb 16, 2014 | 1988 Jeep Comanche

1 Answer

Rear brakes lock when press brake pedal.


get is serviced.

its stuck in , low bed (loaded) mode. the lever is or parts in side

stuck in full load mode.

and guess what, if you bypass the valve, what will happen

the rear brake will lock, going fast and if on wet or worse roads. 10x worse. its there for a reason. to lower the brake pressure with no pickup bed load. or not heavy trailer tongue weight.



ever consider the rear brakes are bad. first. and not the valve.



service the rear shoes and slaves.

then check the bypass.



Does the truck still have the height sensing brake line bracket and line connected into the prop valve?



http://www.jeepforum.com/forum/f53/bad-proportioning-valve-any-ideas-1127468/#post10505224







here is the valve.

sold at , JEEP.



http://www.factorychryslerparts.com/products/JEEP/1988/COMANCHE/VALVE--Proportioning--VALVE--Proportioning--ECE-198789--1989--Except-France--Italy--1990--KDX--KDX-After-3-1-93--KDX-Up-to-3-1-93/4520728/52009114.html



Chysler p/n

52009114 ; 52003118



google that and find them for $75

Feb 16, 2014 | 1988 Jeep Comanche

1 Answer

Hi I am from Norway and have replaced my proportion valve for rear brakes on my Corolla 1996 1,3 xli wagon.I am wondering how I can bleed off air and flush back to new brake fluid.Do I need to connect a...


None of those things . Just bleed the brakes normally starting from the longest line and ending with the shortest. The proportioning valve will always let brake fluid through, just not enough to lock up the rear brakes until you press heavy on the pedal . It is there so that full pressure to the large front brakes is reduce in proportion to the smaller rear brakes.

Jan 23, 2014 | 1996 Toyota Corolla

1 Answer

PROCEURE FOR REPLACING BRAKE LIGHT SWITCH ON 86 JEEP COMANCHE


Buy a new one at a parts store, install it. Generally you will find that is is bolted to the brake pedal arm, just high enough that you cannot accidentally hit it with your foot. Cost less than 20 bucks and takes less than 20 minutes.

Sep 30, 2010 | 1988 Jeep Comanche

2 Answers

IM WORKING ON A 88 OLDS 98 I REPLACED THE MASTER CYL. TWICE BOTH HOSES PADS ADJUSTED THE REAR BRAKES AND BLED 2 QTS. OF FLUID THROUGH IT AND STILL I HAVE A CRAPPY PEDAL IT FEELS LIKE THERE IS NO PRESSURE...


Have you changed the brake hoses on the front going to the brake caliper?If not,this could be the problem,also,when bleeding,only pump the pedal one time upon releasing the bleeder screw,do not pump the pedal,start at the master cylinder,then the right rear,and the left rear,and the right front and left front in that order,adjust the rear brakes to where the brakes are dragging pretty good,but are not locking up,

Aug 17, 2010 | 1988 Oldsmobile Delta 88

2 Answers

A master cylinder has a restricted compensator valve what problem will i most likely find with the pedal?


If your valve becomes defective then the brake pressure ratio to the front and the rear brakes will change. You will see or feel a difference. the front-end may nose dive or lock-up. The rear brakes may react the same way.

May 12, 2009 | 1998 Ford Explorer

2 Answers

Break Lights won't come on in my 1988 Jeep Comanche


Why replace the whole fuse box? That's rediculous. If you can't find the fuse box, just fix the affected circuit. Did they check the brake switch?

Nov 25, 2008 | 1988 Jeep Comanche

Not finding what you are looking for?
Cars & Trucks Logo

175 people viewed this question

Ask a Question

Usually answered in minutes!

Top Jeep Experts

yadayada
yadayada

Level 3 Expert

74945 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22095 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

7697 Answers

Are you a Jeep Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...