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Costly Break

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Old 06-20-2013 | 12:17 PM
  #1  
bob of the rockies's Avatar
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From: Arvada Colorado
Year: 1989
Model: Cherokee
Default Costly Break

By the time I decide to replace my engine I had already put 5 grand into the machine. Having no brakes I methodically replaced every component in the system but ended up having brakes as bad as the original. I took it to a mechanic and he said he done a compression test and it was reading 213-217 when it should be reading 230-250. I confirmed. The mechanic also said the vacuum to the booster was low because of the compression being so low. After replacing the engine I still have a brake problem, I haven't checked the vacuum yet and the new engine has less than a mile on it.

Thanks and any insight would be helpful.
Old 06-20-2013 | 01:04 PM
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From: Newport, pa
Year: 1997
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I'm not good at sugar coating....but...you got ripped off, those compression numbers are more then fine. Can you explain your brakes more? Mushy pedal? Hard pedal? Have to put it the the floor to get any brakes? What did you replace exactly?
Old 06-20-2013 | 02:21 PM
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From: Arvada Colorado
Year: 1989
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Default Costly Break

I didn't get ripped. I got the great satisfaction of working on my own vehicle...hmmm. And it had 140 thou on it. It was due.

I replaced everything in the brake system except for the steel lines. When bleeding I found no obstruction. I replaced the booster and the master twice (under warranty).

My brakes hit very near to the floor and I get no stopping power whatsoever. When I get done trying to align the exhaust (another story) I will check the vacuum to the booster.

Last edited by bob of the rockies; 06-21-2013 at 12:48 AM.
Old 06-20-2013 | 02:50 PM
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From: Newport, pa
Year: 1997
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Does it have abs?
And did you bench bleed the MC before installing it. Also, when bleeding the brakes, are you getting fluid? A little bit?a lot? Bubbles? If you turn the Jeep off, pump the brakes a few times, then press the pedal down, does three pedal sink add you hold pressure on it like there is a leak?

Last edited by foxmxrcer; 06-20-2013 at 02:52 PM.
Old 06-20-2013 | 02:53 PM
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From: Broward County Fl.
Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
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Rear brakes adjusted yet ? Front calipers bleeders on bottom ?
Old 06-20-2013 | 03:20 PM
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From: California
Year: 1989
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I see you have an 89 (same as mine). What size tires? If you're running 33ish" or larger you can expect the brakes to suck with stock components. Unless you start doing mods you have no option other than OEM pads and crappy brakes.
Old 06-20-2013 | 03:24 PM
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From: Broward County Fl.
Year: 1989 xj sport 2dr
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Engine: 12 hole bosch Injectors
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Originally Posted by McCaffrey
I see you have an 89 (same as mine). What size tires? If you're running 33ish" or larger you can expect the brakes to suck with stock components. Unless you start doing mods you have no option other than OEM pads and crappy brakes.
There crappy with stock tires..Double diaphragm booster upgrade best upgrade ive done by far.
Old 06-20-2013 | 03:24 PM
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From: Roanoke, VA
Year: 1990
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Does it have a 35 rear? If so you got seriously ripped off. Your ABS motor probably went dry. Take it to a good mechanic or find out how to run the ABS motor to bleed it.
Old 06-20-2013 | 03:27 PM
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From: California
Year: 1989
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Originally Posted by freegdr
There crappy with stock tires..Double diaphragm booster upgrade best upgrade ive done by far.
Agreed. I did the ZJ booster/master-cyl upgrade too. Definitely worth it. Next is to swap in later model knuckles so I have a choice of aftermarket pads. My buddy did a rear-disc conversion but I doubt I'll go that far.
Old 06-20-2013 | 03:32 PM
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From: Broward County Fl.
Year: 1989 xj sport 2dr
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Engine: 12 hole bosch Injectors
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Originally Posted by McCaffrey
Agreed. I did the ZJ booster/master-cyl upgrade too. Definitely worth it. Next is to swap in later model knuckles so I have a choice of aftermarket pads. My buddy did a rear-disc conversion but I doubt I'll go that far.
Next time im doing rear shoes im doing it got a 96.5 8.25 410 gears in mine.
Old 06-20-2013 | 04:03 PM
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Like said, all else in order, the pedal free-play is directly linked to the adjustment of the rear shoes. The auto adjusters barely work, if at all.
I go through the slot, adjust them till its pretty stiff, then back it off, pressing the brake to seat them now and then.

Also like said, the bleeders on the calipers go up. The calipers will actually fit on the wrong side, upside down.
Old 06-20-2013 | 04:16 PM
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From: California
Year: 1989
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Going through that hole on the rear is next to impossible for mortals. I take off the drum, adjust until I can almost not get the drum back on.
Old 06-20-2013 | 04:22 PM
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From: Ware Shoals, SC
Year: 1993
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Engine: 4.0L
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Going through the hole is easy. A flathead screwdriver and a few minutes each side.

About as easy as it gets.

Adjust rears and bleed and bleed and bleed again.

Most brake problems are from those two things.
Old 06-20-2013 | 04:27 PM
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Originally Posted by McCaffrey
Going through that hole on the rear is next to impossible for mortals. I take off the drum, adjust until I can almost not get the drum back on.
You do know there is a tool. Vaguely like a small, drop-forged spatula.
If you have any lip at all you are gonna end up with more play in your petal. Ok I guess, but it sure feels nice to have it right up, solid! (it really maters, that adjustment)
Old 06-20-2013 | 04:41 PM
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From: California
Year: 1989
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Yeah I have a couple of the tools but I'm just way to lazy to learn to use them I guess. Jack, tire/drum off is just way quicker for me.


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