crappy brake's
#16
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Year: 1997
Model: Cherokee
Engine: 4.0L
Do the rear drum adjuster star wheels work properly? If you have a huge gap for the rear shoes to move before they contact the drum you won't build up any pressure to the fronts. Drums/shoes need to be set pretty close to get a good feeling pedal.
#17
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Year: 1997
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Old school stuff was WAY heavier and could be machined a few times before it got too thin.
#18
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Year: 1989
Model: Cherokee
Engine: 4.0
Is the problem when your just sitting there in park and you push the pedal? Is that when you don't like the feel?
Or is it when you are actually moving and you don't like how it seems to take forever for you to stop?
If it's the first then you do indeed have a problem in your brake's hydraulic system. You either have something being compressed (air) or something swelling from the pressure (rubber lines). If the brake fluid got contaminated, and believe me it does happen, the rubber used to hold the fluid in the system at the master cylinder or the slaves (caliper/wheel cylinder), and even the rubber lines, will start to swell from that contamination and will compress when force is applied.
The only cure is removal of all rubber parts and cleaning of the steel lines with an appropriate brake line cleaner. then replace all rubber containing parts.
If it's the second then that is a much simpler fix. Your brake pads and shoes WILL glaze over when they get really hot! Sometimes it's as simple as taking some 80 grit sandpaper and roughing up the surface. DON"T breath the dust!!! Other times the rotors and /or drums will need to be resurfaced if they have enough material left on them. You should do this when replacing pads or shoes anyways.
When I first became a mechanic back when dinasoars roamed, no brake job was complete until the drums were turned on a lathe. this left a nice new surface for the shoes to work on. Now it's just replace the shoes or pads and replace the rotors or drums if they are cracked or broken. Nothing is done to give them a new surface for the new pads to work on.
Scary!
Or is it when you are actually moving and you don't like how it seems to take forever for you to stop?
If it's the first then you do indeed have a problem in your brake's hydraulic system. You either have something being compressed (air) or something swelling from the pressure (rubber lines). If the brake fluid got contaminated, and believe me it does happen, the rubber used to hold the fluid in the system at the master cylinder or the slaves (caliper/wheel cylinder), and even the rubber lines, will start to swell from that contamination and will compress when force is applied.
The only cure is removal of all rubber parts and cleaning of the steel lines with an appropriate brake line cleaner. then replace all rubber containing parts.
If it's the second then that is a much simpler fix. Your brake pads and shoes WILL glaze over when they get really hot! Sometimes it's as simple as taking some 80 grit sandpaper and roughing up the surface. DON"T breath the dust!!! Other times the rotors and /or drums will need to be resurfaced if they have enough material left on them. You should do this when replacing pads or shoes anyways.
When I first became a mechanic back when dinasoars roamed, no brake job was complete until the drums were turned on a lathe. this left a nice new surface for the shoes to work on. Now it's just replace the shoes or pads and replace the rotors or drums if they are cracked or broken. Nothing is done to give them a new surface for the new pads to work on.
Scary!
#19
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Year: 1989
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try using either a line crimp tool or a pair of vicegrips and clamp your rear hoses see if that helps if not, go to your fronts see if that helps. if not clamp all four pump the pedal up and keep constant pressure on the pedal if it bleeds down then your master is bad,they can be bad outta the box if they have sat on the shelf to long.if you clamp on the upper part of the soft line you will eliminate any kinda if line swelling. at least you can eliminate some of the guessing and replacing for no reason.also it is not your booster it will get a hard pedal when bad.
#20
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Year: 1989
Model: Cherokee
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well i did clamp my line's and my pedle felt a hole lot stiffer. so i went and pulled some lines off a xj my sister wrecked a year or so ago! The lines i got look great so tomarrow i will be replacing them and bleeding. hope it work's
#21
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Year: 1991
Model: Cherokee
Engine: 4.0 litre
Never saw where you checked the individual wheel cylinders. A good outside reference is drip patterns on the inside of the tire.
A failed cylinder will make it hard to stop, and the pedal go close to the floor.
So will air in the lines. Do a good brake bleed all around. Monitor the fluid in the M cylinder, never get it too low.
Also check that the hose to the booster is not collapsing.
A failed cylinder will make it hard to stop, and the pedal go close to the floor.
So will air in the lines. Do a good brake bleed all around. Monitor the fluid in the M cylinder, never get it too low.
Also check that the hose to the booster is not collapsing.
Last edited by Doc Brnard; 09-13-2010 at 01:47 AM.
#23
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Year: 1996
Model: Cherokee
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i am curious too.... so i had really good pedal pressure and good stopping power, then i stuck my jeep on its side. It was there maybe 45 minutes on its driver side. Well when we got it flipped back over the pedal pressure went to crap... No fluid leaked, the MC is still full of fluid and i have decent braking but no pressure...
#24
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Year: 1996
Model: Cherokee
Engine: 4.0
I had trouble on my Volvo with a soft pedal/poor braking.
Finally tracked it down to one of the front calipers was stuck on the pins.
The calipers need to be able to float back and forth, to apply the same squeeze to both sides of the rotor. If the pins/bolts/bushings the caliper is mounted with get corroded/seized up, the caliper really only pushes on one side of the rotor. The pad on the other side gets worn (the rotor and caliper mounting bracket bend far enough to put some pressure on). The flex in the rotor and bracket give a soft pedal.
Check the front calipers, that they are free-floating on the mountings.
Another clue is the inner pad being worn much more than the outer pad.
Finally tracked it down to one of the front calipers was stuck on the pins.
The calipers need to be able to float back and forth, to apply the same squeeze to both sides of the rotor. If the pins/bolts/bushings the caliper is mounted with get corroded/seized up, the caliper really only pushes on one side of the rotor. The pad on the other side gets worn (the rotor and caliper mounting bracket bend far enough to put some pressure on). The flex in the rotor and bracket give a soft pedal.
Check the front calipers, that they are free-floating on the mountings.
Another clue is the inner pad being worn much more than the outer pad.
#25
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Year: 1998
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mine is doing something very similar. i always have air in the back driverside line. no where else, no leaks (that ive seen), and fluid in the master cylinder
#27
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Year: 1989
Model: Cherokee
Engine: 4.0L
I surprised no one has posted this yet. And a little research would have shown you this.
https://www.cherokeeforum.com/f51/xj...-upgrade-3352/
https://www.cherokeeforum.com/f51/xj...-upgrade-3352/