Problems after brake upgrade - Need Advice
 

Hey Guys,

I hung around while a shop upgraded my 87 Carrera to 996 C2 Calipers and Rotors on Saturday. I'd prefer not to name names until I find out what's required to fix the issues. Suffice it to say, due to what I experienced at the shop and now with my car, I do not feel comfortable to have this shop touch my car again. I'm kicking myself for not doing proper due diligence and will work with another shop to correct the issues - even if that means more $$. Once I understand the extent of the fallout, I will post another thread to convey my experience regarding this shop, so that others considering similar upgrades can make informed decisions.

Please keep in mind that I'm a novice. I hired a professional shop for the knowledge and skilled labor that I do not have. As these issues unfolded, it seemed off to me, but I naively trusted the judgment of the professional I hired.

1. The shop owner rebuilt the calipers. He put the very first piston in backwards. Realizing his mistake, he used compressed air to pop it back out. He ended up chipping the back of the piston when it slammed against the opposing side of the caliper, creating jagged edges. He decided to file down these edges and move forward. It didn't seem that there was any material that would have damaged the piston bore, but it's certainly possible. Should the piston be replaced? Does this make the whole caliper a big paper weight?

2. I'm not sure what the correct process is for replacing a brake master cylinder, but it seems to me that corrosive brake fluid should be drained prior to replacement. Perhaps I'm wrong. Regardless, the owner did not opt to drain. He dripped brake fluid all around the master cylinder and brake booster area during replacement. I kept sopping it up with shop towels as best I could. Any concerns here? Should the effected surface be treated? Or is sopping it up good enough?

3. After mounting all of the calipers and rotors, the owner began bleeding the brakes, as I manned the brake pedal. He discovered that brake fluid was squirting out of one of the front 36mm pistons due to a new pressure seal being damaged during installation. He decided to fix the problem by replacing the damaged 36 mm seal with a 37mm seal from an SC rebuild kit, as that was the best replacement he had on hand. He remounted the caliper, bled the brakes and no leaks. Any concerns here?

4. On the drive home, I noticed two items that I think may be related. My oil temps were running 25 degrees higher than normal and I began to hear a loud hum coming from the wheels at speed when no brake was applied. Is it possible that the brake pistons are not fully retracting? If so, then the pads may be pushing against the rotors NOT under braking. It seems that this could account for the hum, and, because the engine is working harder to overcome the friction, it may also be causing the oil temps to rise. Any thoughts on this? Is there a process I should be going through to get the new pads and seals to seat properly?

5. Under hard braking, the car consistently lurches to the driver's side. I had my wife try as well to verify that I wasn't causing with lurching with the steering wheel. Same result. Any thoughts on what could be the problem?

As always, thanks for your generous input. Guys like me wouldn't be able to afford a 911 if it weren't for this forum!

definitely rinse the brake fluid spill area with water. but really that should be done right after it happens. if you had a sticking caliper, the wheel would be incredibly hot after a few miles of driving (much more so than normal and the other wheels with non-sticking calipers). I've never heard of a shop that lets the customer help around the shop. most with insurance have pretty strict rules against that. Sounds like you should go to a new shop.

I dont think water will touch brake fluid, you need to use brake cleaner which may screw up the paint.

If a caliper is dragging enough to cause the motor too run hot it will be smokin hot after a couple of minutes.

What a mess. If I want crappy work done on my car i do it myself :-)

Or maybe it always goes like this but you dont usually see it...like politics and sausage :-)

If you are not an accomplished DIY budget upgrades are probably a bad idea. Go with the $4500 totally engineered plug and play solution with all new parts.

Interesting upgrade, once you get it sorted it will be interesting to see how it works.

Oh, I think I have seen people change MCs like that, I guess the idea is you keep fluid in the lines and have to do less bleeding? I would have turkey basted out some so it did not slop everywhere but you are going to have some drips when you take the lines off I would think.

Find a new shop and have them go through the whole system.

b/f will eat the paint, get it off if it's not already too late

Thanks guys. I know just the shop to take it to, but they may not be able to take a look at it for a few weeks. What's the consensus on how to treat the surface exposed to brake fluid? Apply brake cleaner immediately and then worry about the paint later on?

brake cleaner will remove paint.

i call bs

Was the wrench's favorite tool a pair of Vice Grips?

Certain brake cleaners WILL damage paint. That is a fact. Others may not damage paint if used sparingly and quickly. Brake cleaners are solvents.

a novice mistake. anyone who has ever rebuilt a caliper before knows to put a piece of wood inside the caliper to keep the pistons from shooting out. and putting a piston in backwards?? has this guy ever rebuilt a caliper before? he damaged it, he owes you a new one.

that piston is a paper weight. these pistons are anodized aluminum. as soon as the anodizing is compromised, they begin to corrode. if there is any damage at all on the sides of the piston, it will leak. not if. when.

just plain sloppy work. and a novice mistake. anyone who has ever changed a master cylinder knows to use a vacuum tool to empty the reservoir first. heck, even a turkey baster can do the job. brake fluid will dissolve paint. even if you wiped most of it up with towels, the bit of residue left is enough to melt the paint. i would rinse the area with generous amounts of water. then rinse some more.

another common mistake. there is a special caliper piston lube you can use when inserting the pistons into the new seals, to make them slide in easier. if he tried to push them in dry, he probably nicked the edge of the seal, causing the leak. using a wrong-sized seal is dangerous and wrong... not an acceptable solution.

use an ir thermometer gun and measure the rotor temps after going for a drive. that will tell you if any of them are dragging.

i would be afraid to drive this car. asymmetrical braking? are all the caliper bolts tight?

run away from this clown "mechanic" as fast as you can. if it were me, i might even be inclined to get an estimate at a reputable shop to repair the damage he has done, then ask the clown to reimburse you. take him to small claims court if he declines.

I hope that the calipers are on the right side and the crossover pipes are changed on the other side of the caliper...

Really bad luck with the repair guy... I have to ask, what kind of repair shop lets you to go and help them? Usually the shops have signs that customers are not even allowed to be in the workshop area.

Take it to a proper shop and send the bill to the original shop...

I like that you had your wife test it.:D

Sorry for the joke. Good luck. By the way, does the engine run hot if you just leave it idling? This may help determine if the two conditions are related. You didn't mention if he did any other "work" on the car (like an oil change).

Guys,

Thank you for the input. It's helpful to hear validation from you on these issues. I understand the concern that a few of you have presented regarding the shop and its practices. Believe me - I share them! My first goal is to figure out what's wrong with the car and quantify the cost to fix it. I'd like to keep the focus objective and not slander reputations needlessly. Though it sounds clear that there was negligence, I'm going to give them the benefit of the doubt for the time being and let the facts speak for themselves as they are evidenced. I will have a reputable shop go through the "upgrades" and report the facts here.


No oil change. The work included: installation of brake adapters, C2 996 rotors and calipers and the turbo master cylinder.

And thank you for the humor. It's good to keep it light!

If your brakes are dragging they can overheat to the point they catch on fire, careful. Since brake fluid is basically alcohol, water will wash it off when it happens, if is gooey now I don't think it would help, but I would still flush the area. Some brake cleaners will damage some paints.
If you tell us where you are I am sure someone here can recommend a good shop to redo your brakes.
It's happened to us all at some point or another.

Brake fluid is a dimethyl polyoxy ether. It is a great solvent for paint and other organics. It is completely soluble in water. Just spray the area with water and it will remove any that still remains. The brake master cylinder is under the car in front of the brake pedal and drips onto a skid plate which is painted but is usually already a little rusty. The next time you get a chance, jack up the car, undo the four bolts/nuts that hold the skid plate in place, spray it off, degrease it and repaint it with Rustoleum or spray undercoating. That's what I did the last time I was under there. The whole process takes about 15 minutes. The dripping brake fluid should not have damaged anything since it is under the center of the car and well away from any beautiful painted parts.

I like to use something like Gunk to clean the brake fluid, a better water soluable degreaser, hose it down with the gunk (hopefully not the "foamey brite" that is not much of a degreaser), then hit it with the water hose.

Good luck on this.

Regards

Spray some on a spot in the middle of your hood and wipe it off with a different colored rag... let us know what you find out.

Water works just fine.

try jacking the car up and spinning the wheels. any amount of drag that would cause elevated oil temps should be noticed when spining the wheel.

His car is an '87, so the master cylinder is up top in the front trunk area, bolted to the power brake booster. Any brake fluid will damage the paint in the trunk area, and can drip down onto the driver's feet. At the extreme, the brake fluid might get on the pedal cluster, swelling the pivot bushings.

Here are a couple of thoughts.....
I assume you had this clown (I considered calling him something else but this is a family site) install the 23mm master? This requires disconnecting the long bar that goes from the brake pedal cluster up to the pivot fulcrum to compress the master cylinder. It's pretty long, and it's adjustable for length. Is is possible the clown mis-adjusted the bar and all 4 brakes are dragging?

Also, often times the large vacuum hose connected to the side of the power brake booster is disconnected to get better access to the master cylinder to change it. Possible Mr Clown forgot to reattach it, and your giant vacuum leak is messing up the air/fuel ratio of the Motronic?

I've done the 996TT brake conversion on two 911s and it's not rocket science. But there are a number of details that need to be watched, things anyone familiar with the brake systems on 911 would know. If it were my car, I'd stop driving the car NOW, and get it to someone who knows what they're doing. The caliper with the chipped piston must be rebuilt with a new piston, but I'd also want to make sure the caliper bore hasn't been scratched by the broken piston. And the caliper with the wrong seal must be repaired with the correct seal. This is just plain dangerous! I'm betting the oversized seal is preventing the piston from retracting.

The fact that this Clown allowed such subpar work out the door is frightening to me. You just don't mess with brakes, peoples' lives are at stake.

Sorry to be so blunt but if these are the things you noticed were done wrong, what other things did he screw up that you didn't see. Do yourself (and all other drivers on the road you might come across) and get the car to a reputable shop to fix this guy's shoddy work.

And for the record, as Dustin Hoffman once put it, "I am an excellent driver..." :cool:

Seriously, I'm not bad (for a lady) - I used to do testing when I was an engineer at BMW. :p Sothereha.

I agree with 175K911 - even if the car isn't dangerous (which it probably is), by driving it around, we'd be putting stress on systems and parts that aren't designed for that type of stress.