Bill Dearborn

Was giving a ride at Watkins Glen today. After a couple of laps I was running through the Bus Stop (turning toward the left to exit) when I heard a loud grinding noise and felt the car vibrate. I said over the intercom "That didn't sound or feel good" and the passenger said "It sure didn't" so I slowed and headed for the pits. Stopped in pit lane and inspected the car especially the right front wheel which is where the sound came from. Didn't see anything. Went back to the garage and let the car cool some. While looking the car over one of the other guys there noticed the back sides of the spokes on the right front wheel were scored and there were metal shavings on the outside of the rim. Looked all over and couldn't see what did that. The caliper didn't have any scoring. A few minutes later I moved the car and saw the cause. One of the pad pin bolts had come loose and backed out of the caliper and when I was cornering hard there was enough deflection for the wheel to hit it. Not sure what caused it to come loose. All of those pins have been frozen in the caliper for over a year. I even broke my #45 Torx bit off trying to get them out. So the next thing on the checklist before heading out for a session is to check those bolts.

Bill

Screamin Z

Bill, We have had the exact same problem happen twice. Once on track and once on street.

On the track it was one of the bolts on the inside of the caliper, Bolt dropped, pad flew out.. piston started grinding off. I knew something felt "off" with the brakes. Came in checked it out. Good thing! If i melted it down any further the piston would have came out. Not a good thing to have happen at WGI.

On the street it was one of the outside ones. Bolt came halfway out and tore 1/2 the spokes out of a ZR1 Replica wheel. Not Cheap.

Dirty Howie

Well now we know how to loosen them up ......


DH

Bill Dearborn

Checking the outside bolts is easy. Checking the inside ones means the wheels come off before you go onto the track again. I noticed you and your Dad had the wheels off quite a bit when we were at WGI with the BMW club. Almost need a pit crew along with you just to do an HPDE.

Running the single piece pads would at least prevent a pad from popping out. You would have to lose 3 of the 4 bolts to lose the pad.

By the way, I answered my own question about how the parking brake would work to stop the car on Monday. Was running hard and noticed the car was starting to pull hard left under braking. Coasted through pit lane and tested the brakes and they felt good but there wasn't a lot of time left in the session so I thought I would go out on track and get a 3 mile cool off lap in. Went up the back straight at about 95. Figured I would tap the brake and turn into the bus stop. Pedal went to the floor. Car slowed some but I decided to take the run off. As soon as I went through the cones I knew it wasn't going to stop, so I pulled the parking brake, stuck my hand out the window and started waving my hand at the flagger. I got a lot of metallic squealing noise from the parking brake but the car didn't slow down any quicker. I exited the run off section at about 20 mph. Luckily, nobody was coming through the bus stop and I was able to get over to the right and into second gear and head to the garage. After a half hour the pedal was solid and stayed that way the rest of the two days. It was a little exciting. Sort of like approaching a red light at a busy intersection and knowing you aren't going to be able to stop.

This brake thing with me and my students has to stop.

Bill

wtknght1

Yep, that happened to me too, so now I do a visual each time I replace the pads.

And ps. if you use the one-piece pads, you only need one of the middle "bolts" just to keep the pad in place. You can use the ones that you take out as "spares" just in case.