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General Forums => The Mess Hall => Topic started by: fatoldcapt on September 21, 2010, 09:07:52 PM

Title: Brake Problem when rolling backwards.
Post by: fatoldcapt on September 21, 2010, 09:07:52 PM
I'm told that stock brakes on the YJ aren't all that effective when rolling backward. As in "can't make it up that hill in 3rd L and have to stop on the grade". This has happened to me several times. It was a big surprise the first time: when I went rolling backward down a ridge, all the while pushing the brake peddle with all my might. At first I thought I might have stalled. And that the vacuum drop had caused my Brake Booster to fail. But, I have had it happen a few times when I know the engine was running and it should have had enough vacuum. Then I discovered that if I pump the brake it will stop. But then again last week I stopped just short of climbing out of a gulley and as I rolled back I found I had no brakes. I even pumped the brake as I was rolling and no change. I eventually got stopped as I arrived on level ground at the bottom of the grade. It stops fine going down hill forward. It stops fine in every other situation.

Okay, with that said, have any of you had a similar problem? Is there a cause? A cure?
Any advise would be appreciated!

94 YJ, 5 speed, 31's
Title: Re: Brake Problem when rolling backwards.
Post by: sharpxmen on September 21, 2010, 09:48:04 PM
i'm going to guess the brake shoes are not adjusted properly (or worn out severely) or your proportioning valve is bad

when rolling backwards the weight of the Jeep is on the rear axle, as the rear brakes have less braking pressure it is normal to have to brake harder but you should still stop.
Title: Re: Brake Problem when rolling backwards.
Post by: Jeffy on September 21, 2010, 10:38:57 PM
Most then likely need to adjust the brakes.  Probably need to clean the insides of the drums and manually adjust the brakes.
Title: Re: Brake Problem when rolling backwards.
Post by: sbsg2005 on September 22, 2010, 11:14:14 AM
i have had this twice both time while climbing a steep grade. the first time i was winching over the and when we got to the top i pulled forward to release tension on the cable hit the clutch and brake and immediatly startd to roll back down but the cable save my rear. The second time it was on a short but near verticle climb up a creek bank. When i got over the top and tried to stop no brakes a yota stopped me this time. i have 4 wheel disc and can lock all the tires up on dry pavement. my issue was suspension flex pulling the lines and kinking them just a little bit. cause the lines not to hold any residual pressure. this meant i had to get the line pressure back up to stop. longer brake lines fixed the issue. i hope.
Title: Re: Brake Problem when rolling backwards.
Post by: fatoldcapt on September 22, 2010, 09:54:46 PM
Thanks for the advice. I'll check out your suggestions. To be honest, I haven't taken a look at the rear brakes for as long as I've had this jeep. A little over a year. that might just be it. I'll let you know.
Title: Re: Brake Problem when rolling backwards.
Post by: fatoldcapt on October 08, 2010, 10:55:14 PM
I'm told by a buddy at the jeep club (he's a retired mechanic for a jeep dealer) that the drum brakes don't work worth a damn going backward.

But I did take your advise and adjusted up the rear brakes. They seem to work better. Went on a run last week and they functioned okay. I still need to pull the drums and check the pads. It's on my list. Thanks!
Title: Re: Brake Problem when rolling backwards.
Post by: sharpxmen on October 09, 2010, 07:37:53 AM
readjust them again after 1k miles or even more. def check the wear and replace the shoes if they are uneven, that can cause poor braking.
Title: Re: Brake Problem when rolling backwards.
Post by: dwtaylorpdx on October 10, 2010, 11:37:10 PM
They should auto adjust each time you brake in reverse, if it matters the XJ setup on my 44 sucks backwards as well....

The adjusters need serviced way more often than the rest of the system, I take mine apart a couple times a
year and clean the adjuster thoroughly and use a waterproof grease on the threads,, Seems to help.

Dave
Title: Re: Brake Problem when rolling backwards.
Post by: Jeffy on October 11, 2010, 10:16:08 PM
They should auto adjust each time you brake in reverse, if it matters the XJ setup on my 44 sucks backwards as well....

The adjusters need serviced way more often than the rest of the system, I take mine apart a couple times a
year and clean the adjuster thoroughly and use a waterproof grease on the threads,, Seems to help.

Dave
Brakes should auto adjust when you reverse then hit the brakes.

My XJD44 brakes work fine.  Adjust your brakes.
Title: Re: Brake Problem when rolling backwards.
Post by: sharpxmen on October 11, 2010, 10:36:51 PM
Brakes should auto adjust when you reverse then hit the brakes.

My XJD44 brakes work fine.  Adjust your brakes.

they should auto adjust but they don't - maybe they work when brand new but i always had to do it by hand (even with everything cleaned properly).
Title: Re: Brake Problem when rolling backwards.
Post by: Jeffy on October 11, 2010, 10:48:06 PM
they should auto adjust but they don't - maybe they work when brand new but i always had to do it by hand (even with everything cleaned properly).
Which is why I said should...  People don't check their brakes unless there is something wrong usually.  The roller usually gets gunked up and stops ratcheting.

They need to be adjusted so their lightly drag then back off a click or two.  Then try reversing and that should get them adjusted.  You also should adjust the e-brake while you're at it too.