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post #1 of (permalink) Old 07-04-2002, 01:29 PM
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Rear wheel cylinder is leaking brake fluid.

The attached picture shows my right rear wheel. On the inside of it, brake fluid is seeping out and the master cylinder is empty. Therefore, I have a spongy pedal and the "BRAKE" light comes on. When I fill it out and work the pedal for 2 or 3 minutes, whalah! firm pedal and no light. How easy is it to replace a wheel cylinder? I don't have any brake specific tools and don't know anything about brakes, except pad replacement on disc brakes. The Haynes manual doesn't give me specific enough details to give the the confidence to try, but it does mention different approaches depending on if the axle is "Full floating" or not. Is my axle full floating and how do you know? The end result is that I do no want to attempt this if I remove something and a ton of fluid comes rushing out of the axle and then I dissamble the rear drum and can't get it back together correctly or without some $50.00 tool. I'd rather go to a shop for $60.00 and get it done correctly. Is it dangerous to keep filling the master cylinder knowing it's leaking? At some point, might the brakes completely fail or will you always have front brakes even if the rear reservoir had leaked out? Thanks for the brake 101 knowledge. Be gentle I'm a newbie, but at least i'm not a stranger anymore.
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post #2 of (permalink) Old 07-04-2002, 02:13 PM
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Re: Rear wheel cylinder is leaking brake fluid.

Every Jeeper should know how to do brakes. If you don't have one already, buy a Chilton's manual and read up. It should tell you everything you need to know.

The whole process is fairly straight forward, although a bit daunting the first time due to the springs and shoes inside the drum. If the wheel cylinder was leaking that bad, you really should change the brake shoes at this point. It's simply good insurance.
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post #3 of (permalink) Old 07-04-2002, 03:08 PM
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Re: Rear wheel cylinder is leaking brake fluid.

It's not rocket science ..but all the springs and cables in a drum set up can be intimidating to the inexperienced. There are so many different configuration over the years that even the seasoned have to reference the other side (still intact) to put it back together correctly from time to time.

The main problem you may encounter is rusted or siezed fasteners ..particularly the brake line flared nut. This is usually the only problem I've ever encountered. At times the nut is siezed to the brake line and I've had to spin the wheel cylinder out from the backing plate side (at times a challenge).

Give your criteria of not buying a $50.00 tool ..and such I'd say that you are better off having a qualified pro do the job ...but I'd plan on more like $100+ to have it done. The wrench is going to change both sides of shoes ..he's going to charge you cost PLUS mark up on the parts and is probably turn both drums when doing it (btw- you should do the same at a greatly reduced cost).

This is a project well worth the learning curve. This is one of the most basic mechanical task that can pay off BIG in $$$ saved for a relatively simple proceedure that is well within mere mortal capability.

I would invest in a set of line wrenches (not manatory ..but very wise) and a cheap set of brake tools (around $20 at Harbor Freight). Advance Auto has most wheel cylinders for under $15 (all my local parts stores including NAPA want around $25) ..and you can get the drums cut for under $10 each (depending on locally indexed rates).

If you want step by step detail (in real terms) fill out the email part of your profile and some may entertain your needs for personal coaching.

Although you can function under the current conditions for quite some time (I have in the my long history of bailing wire and duct tape "billy rigging") there is little sense to doing it when you either have the ambition, skill, or the wallet to do otherwise.
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post #4 of (permalink) Old 07-04-2002, 03:57 PM
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Re: Rear wheel cylinder is leaking brake fluid.

I just did my back brakes and stuff , all that crap in there is slightly intimidating . Pulling the slave cylinder off is nothing , they are cheap to replace . You have one great tool in your hand ( NO not that ) , you have a dig camera . Snap some picks of the rear brakes as you dissasemble them if your unsure . It will give you reference to fall back on . Let us/me know if you need any help along the way .
Oh , when you get them back together , pull out the 2 little black rubber slugs on the inside backing plate and adjust the adjusters until you can almost stop the wheel , then back off a bit , then you done . You want to hold up the lock , then go forward on the little wheel that has the cogs on it . That takes up the slack for the adjustment .
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post #5 of (permalink) Old 07-04-2002, 04:43 PM
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Re: Rear wheel cylinder is leaking brake fluid.

do one side at a time......the one is a mirror of the other. this way you arent completely screwed if you forget how it came apart
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post #6 of (permalink) Old 07-04-2002, 08:43 PM
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Re: Rear wheel cylinder is leaking brake fluid.

you should be able to buy both tools for under ten bucks.
If you want a self bleeding kit, add another 5.
Go to a autostore, and they have the wrenches specifically for your size wheel cylinder for about 3 bucks, and you really don't need the adjusting tool.
A screwdriver works fine.
It will make it a lot easier if you just buy new everything.
New shoes-10-15
new hardware-8
new wheel cylinder-8 per side
adjusters-2 per side
brakes turned-I don't know..
Do both sides this time, and it might be best to leave one at a time so if you screw up and don't know how to put it back together, you have a fully assembled model on the other side.

1. loosen lug nuts
2.take off wheel
3.take off brake drum
3.A.If brake drum won't come off, look around the backside and find a little rubber plug, or a slot on the bottom side of the backing plate
3.B Insert screwdriver in hole(flathead) and feel around.
There will be an adjuster with a starhead on it, and you want to turn it.
I'm not sure offhand whether it is up or down, but do it one way for a while and see if it gets looser or tighter.If it gets looser, continue doing it that way until you can take it off.
3.C If it is still stuck, bang it with a hammer a few times..
4.Go around back and you will see a line going to the back of the backing plate.
Unbolt it with your tool.
5.You will see in the middle of each shoe two springs and a rod that goes through them.
Push in on the front of the spring cover and turn the rod.
6.Start taking off careful and take a picture(if that is a digi camera you have) to see which springs go were.
Basically just start dissasembling things.
7.Unbolt the wheel cylinder from the backing plate..
8.Reverse everything you have done with the new parts.
9.Bleed your brakes with your brake bleeding kit.

The only problem I can see you having is e-brake, which I have never had..but it shouldn't be too hard.
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