Salty's 2005 330Ci ZHP Jet Black Coupe Restore

[johnrando]

And you checked your brake fluid level?

Sent from my SM-G955U using Tapatalk

[SaltyNC]

And you checked your brake fluid level?

That was the first thing I checked. I also checked to see if the left front (driver) caliper was not releasing pressure, and it was fine. I suspect the seal on the main pisto failed at some time. I'm going to hang the caliper today and try pumping it out with the brake pedal. I think the main piston is seized. These calipers are bad rusty. I may be able to clean up the main piston enough to get it working again until I can get a remanufactured unit in. Thanks!

Salty

[Sockethead]

Most likely, the piston in that caliper is pitted or the groove the seal sits in is corroded and that's what's hanging it up. The caliper usually gets pretty corroded around/in the groove that the seal seats in. They can be a bitch to clean out and get right. Worst case, the groove gets too corroded to hold the seal effectively. The only real way to tell is to pull it apart. If the piston is pitted or scored bad then it needs to be replaced.
I used to rebuild all of my calipers myself but discovered it wasn't worth the time/effort to save a couple of bucks.
If you don't know the history of the car, I'd flush the crap out of the system because water intrusion is basically the only thing that's going to cause a frozen caliper.

[SaltyNC]

Thanks Sockethead.

I planned to change out both tie rod assemblies including outer/inner and boots, today. The first tie rod puller I tried wouldn't work. I could never get it to go under the tie rod knuckle. This is the one that didn't work:
http://a.co/bGGHqpt

So, a trip to Harbor Freight, and this ball joint separator worked:
https://www.harborfreight.com/3-4-qu...tor-99849.html

After getting the outer tie rod free, it was easy peasy to replace it.

Then I went to the left side (driver) and thought I'd push that stuck piston out by pumping the brake pedal, and then work it back in, to see if I could loosen it up just enough to get by for a couple of days. That was a mistake. That piston is out, and it's never going back in. I used a dedicated piston pusher and a makeshift giant C-clamp, and that piston isn't going anywhere. So, no tie rod install for the driver side. It will have to wait.

Of course, I was working smack in the middle of my driveway, blocking all of the other cars. I finally just hung the stuck caliper with a bungie cord from the spring, put the wheel back on with the caliper hanging behind it, and used the parking brake to very slowly and carefully move the car out of the way. What a deal. It looks like the ol' ZHP will be parked until I get the remanufactured calipers in. On a positive note, I took off the caliper bracket and painted it with black caliper paint, and painted the rotor hat shoulder. That looks much better. I'll paint the remanufactured calipers black before installing them.

And absolutely on the brake flush. I'm going to do a complete flush after I get the new calipers on.

Salty

[Sockethead]

Yea those seals swell after being exposed to brake fluid for so long... that sucks about blocking the driveway, I hate it when that happens... there are a few other people that have had bad luck working their cars this weekend... must be that blue super moon ...

That's the same ball joint separator that I got a few years back. It's held up very well.

[SaltyNC]

That's the same ball joint separator that I got a few years back. It's held up very well.

Good deal. I don't think it will see much use with me, but when you need one, nothing else will do.

Salty

[SaltyNC]

The remanufactured calipers I ordered came in, and I was able to get them swapped out this afternoon. I only had to hold a flashlight in my teeth for the last 10 minutes.

My left (driver side) front caliper was sticking. The rotor looked OK, so I ordered some remanufactured calipers from BavAuto. They carry the Nugeon calipers. BavAuto says they don't come with brackets, because Nugeon often ships the wrong bracket with the caliper, but I hit the jackpot, and both calipers had the correct bracket. I guess they do a hot wash or sandblast these things, because they look brand new, and they are the original equipment BMW Ate calipers and brackets. Nugeon replaces the rubber guide bolt boots and caps, the guide bolts, the piston and piston boot, the anti-rattle clip, and the bleed nipple. Nugeon's rubber boots were very soft, and the cap didn't want to stay on, so I swapped them with my original Ate boots and caps. Much better, and the rubber looked perfectly fine after all these years. I also swapped the bleed nipple. The one they include uses a smaller nut, and it looked inferior, so I swapped over the OE nipples. I did use their included anti-rattle clips.

Here is why my caliper was sticking. The boot had failed allowing moisture to rust the piston:


While I had this caliper hanging, it was leaking very slowly, and so after two days, I was worried I would drain the master cylinder, so I ran to AutoZone to see if they carried something just to top up until my Ate fluid came in. They had Pentosin DOT4 LV for $16, but they had Bosch for ~$7. I went with the Bosch. After researching the Bosch, I was shocked at how good it is. Maybe they priced it wrong, but the specs on this Bosch fluid are great, and it's very low viscosity. It interestingly comes in the exact same container as Ate fluid. It has nearly the boiling points of Ate Type 200, but has superior anti-corrosion properties. Ate now has an SL6 fluid that is similar. These are probably both made in the same factory with slightly different formulations.

https://www.boschautoparts.com/docum...0-91edb62866a3
https://www.lelandwest.com/brake-flu...ow=1&SF=3&ST=2


It's so nice having clean brake parts, so I took advantage and degreased them, then painted them black before putting them on the car.


I had ordered some stainless steel brake lines, but they won't be here for a few more days, and since the calipers arrived so quickly, I decided to put them back on, and I'll do the stainless lines when they arrive. It's very quick to swap lines, and I need to do a complete brake flush anyway, so I'll do all that at one time.

For today, I replaced both front brake calipers and brackets.

If anyone is doing this soon, here are some handy torque values:
Front Caliper Bracket Bolts - 16mm: 81 ft lbs (have fun getting those loose the first time)
Caliper Guide Bolts - 7mm allen (int hex) - 22 ft lbs - BMW recommends running them with no lubrication inside rubber boot
Front Hard Line to Brake Line - 11mm (use flare nut wrench)
Brake Line to Front Caliper - 14mm (use flare nut wrench)
OE Bleed nipple - 9mm

Car sat in the rain for two days waiting on calipers, but that rust was gone after the first test drive. The paint is gloss black, and it's reflecting the blue shop towels in these photos.


Now I need to finish up my tie rod job. The right passenger side is installed, but I still need to do the driver side, and then do a quick and dirty alignment job until I can get it into the shop.

Salty

[Sockethead]

Nice that they come pre-painted.

[SaltyNC]

Sockethead, they don't come pre-painted. The do, however, come very clean. They are bare metal but with a thin coating of oil to prevent rust. I wish I had taken a picture of them before I painted them to show how nice they are. It just made the job very easy to degrease them and paint them with caliper paint before I put them on the car.

Salty

[Sockethead]

Alrighty then, nice paint job... Looks like they came that way