1997 850 Rear Calip Question and Front End Question

mika · Post by **mika** » 10 Jul 2015, 07:55

Two questions:

1) I cannot figure out if my front end needs a wheel hub or a CV axle. Symptom: when I go over bigger bumps, or accelerate into a turn, or reverse out of the sloping down driveway each morning, I hear a bag of rocks sound. I tried to reverse on full lock, and the notorious CV clicking did not happen. Furthermore, with the car jacked up, wiggling the wheels at 6 and 12 did not produce much movement. Also, in my records, each axle has been rebuilt with a new boot once. Is there a way to inspect the wheel hub bearing with the wheel off, but axle still in the hub?

2) I think my rear passenger caliper is sticking. For example, when I brake hard at a red light, and then start moving again, I hear a "hush hush hush hush" and then it goes away faster I go. My question is, is the rear caliper brake line any harder to remove than the front one...Just unscrew it? Is rear passenger hard line the one that is recommended to be removed about the trailing arm, or is this hard line best removed at the caliper end? Any tips on how to "plug" it so I minimize brake fluid loss? I do not like bleeding brakes but have assisted twice.

Thank you all

Post by **kahl** » 10 Jul 2015, 08:15

1. The sound you are hearing may be coming from your strut mount. Common failure. Also worn sway bar links can produce a rattle sound. A wheel bearing will pick up noise the faster you go and will sound like a swarm of bees. Are your axle boots still intact?

2. When I have changed calipers I remove the brakeline at the caliper.

Post by **erikv11** » 10 Jul 2015, 08:18

What kahl said!

(1) I have no other great ideas here. It's not the catalytic converter right (bang on it from under the car to check)?

(2) In concept the rears are no different from the fronts. If the fittings are in decent shape then just unscrew the brake line at the caliper. But in practice they see more corrosion, so be sure to presoak with a good penetrant and use a quality flare nut wrench.

Be careful, you don't want to ruin the flare nut. My last two came right off but earlier in my days I remember trashing one of them. All the posting about trailing arm nuts refers to replacing the rear brake hoses, they are not at the caliper they are tucked away. No ingenious methods on the dripping brake fluid, I just move quickly, try to have the replacement caliper all set up and ready to go.

Post by **cn90** » 10 Jul 2015, 09:14

1. Remove front wheel, unbolt caliper and hang it safely.
Spin the hub, if you hear "rock rock" sound, chances are the bearing is going south.

2. The REAR caliper is a sticky business.
If you manage to get it out w/o rounding the nut, then you are golden.
When I did my rear caliper rebuild:
- one side is OK, the nut came out.
- the other side: the nut was seized in place, I rounded it! So I elected to rebuild the caliper in situ.
Basically expel the piston, replaced the seal and boot and done.

So:

a. If your brake line nut is seized and your piston is still good, rebuild in situ, it is much better than
playing around with the metal line. In this case, all you need is the seal+boot kit.

b. If your brake line nut is seized and your piston is rusty, you have 2 choices:
- new caliper but you may need a new brake line, or do the bubble flare wherever you cut the line.
- buy the new piston (or get the piston from junkyard and transplant the piston) and rebuild kit.

I wrote the caliper rebuild procedure in forum if you are interested in the rebuild process.

Post by **JimBee** » 10 Jul 2015, 13:12

My theory about the right rear brake line to caliper fitting is the assembly machine at the factory was set to overtighten it. On several 850's I've worked on all had the overtightened and seized right rear fitting. Others on some threads on this site have reported a similar experience. Heating with a torch and lots of PB Blaster doesn't seem to help to break it loose.

If I have to change that caliper I'm going to cut the line with a tubing cutter at a point where I can work on it, then use a ferrule and union block to extend a new piece of line with flare end already made up to mate to the new caliper.

Car Quest has all the fittings to do this. You'll need to bring a section of line and the new caliper to the store to get the right size line and connecting pieces. If you use the correct pieces it should work.

Some fluid will be lost. If the section of line from the caliper to the new splice is made up with the nut and ferrule and union tightened on that side before you cut the line, you should be able to quickly install the nut and ferrule then connect it to the union without losing too much fluid. The last step will be to bleed the new caliper.

Also, before cutting the line, it would be a good idea to clean the line across the cut point with steel wool, to avoid getting grit in the line and to ensure the ferrule will slip on.

Replacing that entire line is hard to do because the upline fitting is hard to access. Even if you could get to it, there's no guarantee you could break that fitting loose, either.

My left rear caliper seized one February and that wheel locked. I drove on snow covered roads about a mile to a brake shop with the wheel dragging. It was tough getting going from stop signs.

Rebuilt calipers at O'Rielly's are covered with a lifetime limited warranty (at least as of several years ago).

Post by **erikv11** » 10 Jul 2015, 14:07

Mika you can swing by my house and we will try to break it loose!

Also if the caliper is sticking then that rotor will heat up much more quickly than the other side, after letting the car cool (overnight etc.), drive around the block and see if it is getting warm.

Post by **abscate** » 11 Jul 2015, 15:56

If you touch the rotor on a frozen caliper, you get a cool one second sound of your finger tips sizzling which is ruined one second later when your nervous system sends 1Gb of data up your ulnar nerve.

It's a three week process of your fingertip skin blistering and then falling off.

Post by **abscate** » 11 Jul 2015, 16:00

If it comes and goes, it's CV.

Bearings will growl and get noisier and noisier, unless they are spewing balls out

mika · Post by **mika** » 14 Jul 2015, 08:01

Just wanted to thank everyone for their input. I see that most of the regular guys here showed up and spoke their voice.

It is seized. And now rounded off.

Laughed in my face! Hard week for working on cars (stripped the keywave on a b230 crankshaft gear, and then found out the crank pulley went south b/c I pried it off and the rubber lost its balance). I read all the threads about seized nuts on MVS since. I will figure this one out asap somehow!

CN90: the rebuilt kits I see on IPD are "front"....are front and rear interchangeable? I don't see why they wouldn't be.

Erik I will definitely stop by for another job, maybe front brake lines? Me and brake lines never got along. I had a 7/16, and a 11mm.

Post by **abscate** » 15 Jul 2015, 04:48

When you are all in on a rounded flare nut, a massive vice grip is worth a try. until 2008 you could still get the original McCoy from Nebraska, made by Irwin, but I think they are all Chinese now.