StarkRavingPete

HELP!! So, the brakes on my 97 XJ Country went out. Went to Advance AP and the little man behind the counter told me that it was the rear brake cylinders. The wife and I just got finished replacing both of those and we made sure everything was properly bled and tightened and replaced and sealed, etc. So, as a last test, I press the brake pedal in one easy, long push while the vehicle was off. We hear this *pop! fizz! spurt!* sound....and sure enough, the rear driver's side brake cylinder we just replaced burst had burst and is weaping oil! Did we get a bad part from Advance? We put anything together correctly according to Haynes. Does anyone have any insight? Does anyone have a few hours that someone could spare that would trade some wrench turns for beer? I appreciate any feedback. Thank you.

Pete

Bustedback

Could have been a defective unit, even new puppies die every now and then.

DaddyCat

IF you reassembled the brakes correctly then it sounds like you got a bad cylinder. Look here for a nice write up with fotos:
https://www.cherokeeforum.com/f51/ho...kes-d35-45100/

dukie564

yup you got a bad one. Bring that sucker back and get a new one. Make sure they honor the warranty.

2Evil4U

Quick question, just to confirm:

You did have the entire brake assembly back on including the drum before you stepped on the pedal?

If not, you'll just blow out the pistons as there's nothing to hold them in.

dukie564

haha that's a good point

StarkRavingPete

They replaced the cylinder.

However...you're right, I had not put the drums back on before pumping the brake. The pistons don't look damaged, just the one brake cylinder. Or have I ruined the pistons too? (Please tell me I don't need to replace those too, now...)

Greenfishinkayak

Ouch a buddy just did that on his pos Taurus when he was bored he was checking his drums and decided to see how far his brakes would go... Well now they are gone an the idiot keeps driving it with no brake pressure and nonfunctioning ebrake.... Now sounds like a good time to convert them to discs!

wildbill1

You might be able to reassemble the wheel cylinder assembly if no parts are lost, although replacing the assembly might be the next step. As you now know, there's nothing to stop the pistons from coming all the way out except for the drum.

When you get it all assembled again, make sure to adjust the shoes before hitting the road.

Bustedback

Now you tell us the rest of the story. You have answered your own question. Never step on the brake pedal when a drum is off, or a caliper is off. You could have re-assembled the wheel cylinder, and the pistons in a wheel cylinder do not hold any hydraulic pressure, they just back the seals and push out on the shoes. Some scratches are not a problem as long as they move freely in the cylinder.

StarkRavingPete

OK, so we finished up Wednesday night at about 2:30AM after a late start. We got everything back on and in place. Brakes work again!!! There seems to be a few new sounds and the brakes lock up and skid easier than before. But the brakes work...not really sure about that part. Kinda freaks the wife out too.

I should have replaced the shoes when I already had everything off, but an unexpected $200 plumbing emergency put that on the back burner. However, now I know how and what to do, so when I can change the shoes the process should take no time at all.

Thank you all for the suggestions and help! Next big job I need to do, I'll post here for help. Or for a wrench party....with beer....and blackjack and hookers! /bender.

StarkRavingPete

Oh! And yeah, I got another brake cylinder (they took the one that popped and gave me a brand new one) and once that was in place and the shoes adjusted I got the pressure back.