Glove Box Light

Here is some information on a glove box light I made. I bought a keychain flashlight that used a bright blue led for the light. I got it from LL Beans for $20, but I see them for sell everywhere. It is a sapphire crystal led, and two 3-volt lithium batteries. The cells have a 10 year shelf life. All I wanted was the led and the 2 batteries.

I took the light apart and just used the led and the area that holds the batteries, cutting the rest of the body off.

I then acquired a metal cased mercury tilt switch. Durakool (http://www.aecsensors.com) has various tilt switches. I bought part #4929 from Newark Electronics (http://www.newark.com). It was around $5.00, but there was a minimum order, or a $5 penalty. It operates at a plus or minus 7 degree angle. It is very tiny, being around 1/4 inch all round in size. I placed all the parts in a small fuse box (the one that the cylinder type buss automotive fuses come in). It seemed like a perfect candidate since the plastic part of the box slides off easily from the metal top and it is small and shallow.

I drilled a hole in the plastic part of the box for the led to come out, and the rest (batteries in their holder and tilt switch) was placed inside and held in place with electrical tape. I had previously soldered circuit board wire from the tilt switch to the light. Some final touches like an LED holder from radio shack and some chrome tape on the box gives it a more finished look.

This small fuse box was attached to the left side of the glove box and held in place with velcro. The angle of the box had to be adjusted to get the light to turn on and off at the appropriate time when opening and closing the glove box door.

Pleased with the finished results, it puts a nice blue light inside the glovebox that allows me to see the things inside.

Z3 Paint Problems

While in for a service check, I asked the BMW Center of San Antonio, Texas to look at the trunk lid to make an assessment of why the paint was fading. They stated there was nothing they could do and were not sure why it was fading. They thought it was oxidation and tried to buff it out, which did not work. Since the car was past the four year warranty, they would not repair it. Within two months, the faded area spread to almost two-thirds of the trunk lid. Areas on the left rear fender and hood have also appeared. I took the car to a third party paint shop. Their analysis was that the paint was fading between the clear coat and the base paint. If the clear coat got thin enough, it would start peeling off. The only solution is to repaint the affected areas. The fading will only get worse no matter what precautions are taken. Since I have had the vehicle, it has always received the best wax treatment and care. A decision will have to be made whether to invest money into a full vehicle paint job or put it towards a new Z3.

Editors Comments: It’s my impression that BMW Service departments will just about always avoid any kind of paint warranty repairs. I don’t think they are necessarly the guilty party as it’s BMW North America that is ultimately holding the check book. Service departments know they are going to have a hard time getting BMWNA to pay for paint repair warranties and they are just automatically on the defensive. Bottom line, its going to be an up-hill battle and you are probably wasting your time discussing it with the dealerships service advisors. Ask when the BMWNA service rep is going to be in the area and schedule an appointment to meet him. Provide him with the facts, and avoid using the word “internet”.

Stopping Brake Squeaks

For some reason I associate brake squeak with old junker cars. It was embarrassing for me when my Z3 started making those annoying high pitched squeaks every time I came to a stop sign. After some research the solution was cheap and easy.

The first thing I learned was that I misunderstood what brake squeaks were. I thought it was the friction between the brake pad and the disc that caused the squeak. Turns out that most brake squeaks are from the brake pad moving around and rubbing against the caliper.

I had heard of anti-brake squeak stuff before but I always dismissed it because I thought anything between the brake pad and the rotor was a temporary solution at best since it would wear away quickly. Once I learned this stuff was for the back of the brakes everything made since. The guy at the NAPA store laughed and said “can’t tell you how many times I’ve seen this stuff used on the wrong side”. NAPA’s CRC Brake Disc Quiet was roughly $3 a bottle, and it was more than enough for two cars.

It comes out as a thick rubbery goo, and dries in about 10 minutes. Once dry, simply reinstall the brake pad then wipe down the excess red goop that squeezes out. It’s a little messy, but you’re probably wearing rubber gloves when working with brake pads anyway.

Once installed the difference was night and day, no more brake squeaks.

Changing Brake Pads In My BMW

The very first step is verify that you have a 7mm allen wrench, it wasn’t part of my little allen wrench kit so I had to make a quick run to the local hardware store. While you are there you may want to also pick up some rubber gloves. As you know the stock brakes spread break dust everywhere. Once I had the right tool for the job replacing the pads was pretty easy.

The first (and possibly hardest) step was getting the car up on a jack and jack stand. Especially considering the BMW M roadster does not come with a jack. Once that small task was done and the wheel was removed the rest was fairly easy.

If you are working with the right rear wheel or the left front wheel there will be a brake sensor (blue arrow). This sensor is clipped into a notched out area of the brake pad. Get your fingers as close to the brake sensor as possible and wiggle-pull it free.

The next step is to remove the retaining spring. I used a few choice curse words to aid in its removal, you will want to squeeze and push in on the clip (red arrows) while lifting and pulling out on the back (yellow arrows).

On the back side of the brake, there are two plastic caps that cover the 7mm hex bit guide screws. The plastic caps can be pulled off with your hands, they are snapped into a rubber housing. Once the caps are out of your way use the 7mm allen wrench to remove the guide screws. The screws should be completely removed.

The only thing holding the brakes in place now is brakes themselves. If you are having trouble working the caliper free apply constant even pressure on the brake piston by pull on the outside of the brake (use caution – remember your car is up on a jack and jack stand). You are not going to be able to compress the piston with a single yank, just use medium sustained pressure and you will feel the piston loose pressure and release. It took me about 40 seconds of medium pressure for this to happen.

Once the caliper is removed, replace the inner and outer brake pad. The inner brake pad is clipped into the brake piston, pull straight out to remove.

The outer brake pad was just kind of stuck there. Note the sticky stuff on the stock outer brake pad, if the new pads you are installing do not have this you will probably want to take a look at my Stopping Brake Squeaks article.

Once you have the new pads in place, you may have to put some more pressure on the piston in order to reinstall the brake caliper since the new brake pads should be thicker than the worn ones you just removed. The rest of the installation is just retracing the steps you took to remove the caliper.

TWO VERY IMPORTANT NOTES: You will need to pump your brake pedal several times to get pressure back to the brakes. Use extra caution the first time you drive after replacing the pads.

When new, brake pads have a slightly rounded surface that ensures once broken in you get a maximum contact patch. But until they get fully broken in you are concentrating the friction to a smaller patch. This means that when brand new the friction/heat is in a smaller area so you should avoid overheating the rotors.

Porterfield Brake Pads

Pros: Possibly Better Performance, Almost No Brake Dust Mess
Cons: Initial Brake Squeal, but Easily Fixed
Cost: $94 Front, $75 Rear from MyRoadster.net

After 60,000 miles on the stock brake pads I assumed I was getting close to needing to change them. I’ve been pleased with the performance of the stock BMW brake pads, but the brake dust was always a mess. The photo to the right is for real, this is how my wheels usually look. I wanted to find some replacement pads that offered equal performance but without all the brake dust mess.

The Porterfield brand caught my attention, it appeared it may be what I was looking for. MyRoadster.Net carried the Porterfield brand so I asked some questions via their info@myroadster.net address. I learned that Porterfield makes three different kinds of brake pads depending on your needs.

* R-4 for track use only

* R-4S for street and light competition

* R-E for endurance racing events

The “Porterfield R4-S Carbon/Kevlar Street Brake Pads” matched my needs, and the feature list impressed me.

* Low Dust

* Light Pedal Effort

* Rotor Friendly

* High Friction, Hot or Cold

* Low Wear Rate

* Fastest Stopping Road Pad Available!

* Friction Coefficient:

* OEM: Between .2 and .3

* Porterfield: .4

* Temperature Tolerance:

* OEM: 500-700 degrees F

* Porterfield: 1,100 degrees F

After installing the pads (see ///MZ3.Net’s brake pad installation article for details) I resisted the urge to make any judgements until I knew the pads were really broken in. I was also cautioned to avoid excess hard breaking during this initial period. When new, brake pads have a slightly rounded surface that ensures once broken in you get a maximum contact patch. But until they get fully broken in you are concentrating the friction to a smaller patch. This means that when brand new the friction/heat is in a smaller area so you should avoid overheating the rotors. At least that’s how a BMW tech explained it to me, it wasn’t something specific to the Porterfield brand, just a general caution for all new brake pads.

8,000 Mile Update: How does the saying go, if I knew then what I know now….

I put up with the stock brakes and their mess for 60,000 miles. From my experience, the Porterfield R4-S brakes offer at least equal performance (maybe even a little better) but with almost no brake dust mess. That was exactly what I was looking for so I am very happy with the Porterfield R4-S pads brakes. My only complaint with them was some initial brake squeal, but that was easily fixed (see Stopping Brake Squeaks article for details). For the cost ($94 front, $75 rear) and backed with MyRoadster.Net’s money back guarantee, the Porterfield R4-S pads seem to be what most Z3 owners should be looking for when either they need to replace their stock pads, or are just fed up with cleaning up after the BMW pads.