tighten those bolts

[petevw]

i was leaning out my car tonight. data log and accelerate onto the highway, and pull off at the next exit. look at the run, adjust EFI accordingly, and go out again.

now everytime i hit the brake i felt a little thunk. i had the front end apart last week to drop another 1/2' and flip the tie rods. i noticed some play in the steering box. so i thought the slop was the slight thunk i was feeling.

after the 3rd pass up the highway, i slowed down at the off ramp, hit the brakes, felt/heard a LOUD thunk. heard something come off and hit the fender/kickplate/underside

downshifted hard though the gears, while killing the handbrake. got it on the shoulder. got out looked at the tierods/control arms/struts and gave them all a good shake. seems ok. got in the car rolled forward, hit the brake... THUMP. got out grabed the driver side caliper and gave it a SHAKE. the top bolt had FALLEN OUT

walked up the ramp, found the other bolt, tightened them both up (tool box in car), cursed at how stupid/lucky i was. got back in the car, hit the brake, thump was GONE. cursed again at myself
continued doing a few more runs, getting my AF at WOT from 12.2 to 13.8.

the only thing i can figure is, i tightened the bolts by hand, went to the other side installed the caliper, cranked them down with the strut/tierods and never went back to the driver caliper.

could have been way worse... don't really want to think what could have happened. i hit 100mph many times that night.

anyways, DOUBLE CHECK EVERYTHING!

pete

[boygenius]

Scary story Pete, glad nothing worse happened. Just a few tech tips I learned over the years to help others avoid your scary situation...
1. Never finger tighten anything, always leave the bolts or nuts loose by a couple of threads so you can se them.
2. I always take a paint pen and mark the bolts I have tightened just so I don't have to remember if I tightened them. If they are painted they are tight.
3. Saftey wire doesn't hurt either.

[Bruce2]

The exact same thing happened to me last year. Left top bolt. I attributed it to the fact that I used neverseez. Since I always use a torque wrench, I figure I need to up the torque to compensate for the lubrication effects of the neverseez.
I was thinking what would have happened if the bottom bolt fell out instead of the top one. With the top bolt out, the force of the rotor on the caliper pulls it in. But if the bottom one was out, the caliper would swing out at the bottom wedging it against the spinning wheel. I'm certain it would instantly lock the wheel.

[petevw]

boygenius: great tips :agree:

Originally Posted by Bruce2

I was thinking what would have happened if the bottom bolt fell out instead of the top one. With the top bolt out, the force of the rotor on the caliper pulls it in. But if the bottom one was out, the caliper would swing out at the bottom wedging it against the spinning wheel. I'm certain it would instantly lock the wheel.

thought about that for awhile. locking up a front tire into a off ramp....that could turn into a big mess.

[zen]

good idea if you have done suspension work to get a few miles on it, get it in the air and tighten everything down again. i am getting ready to do just that.

[NO_H2O]

LOCKTITE :agree:

[Pillow]

Yup, LocTite.

[Jeza]

loctite only helps if you have actually tightened the bolt up in the first place, it won't stop a finger tight bolt from being only finger tight.

I double and triple check all bolts before taking the car out. But stories like these remind us to check our work. Thanks Pete

I have similarly scary (also stupid) story.

Driving home from the panel beaters along the back residential roads (all 50kmph) and I noticed the steering was getting progressivly lighter and really sloppy. Got home and looked under the car to find the control arm / sway bar bolt had almost fallen off one side!!!! So why was the pin not in place, because I assumed I had done the bolt up nice and tight and was only doing a short jaunt to the panel beaters. I was also planning on pulling the front apart again when I got back. Not a good excuse. I was lucky.

I also find it amusing that we don't stop to check something immediately after we hear a thump or feel something go odd.....

Cheers
Jeremy

[Racelook]

It's not a car, but....

My cousin was also forgotten to check if he had tighten te bolts of his caliper on his scooter.. He drives on, brakes quite hard.. calipers breaks lose... 2 carterhalfs (where the drive"train" of an scooter is hide) broken.. (that cost big cash!!! and the wheel was bent..

Use locktite and double check

GRrt Wiebrand

[petevw]

Originally Posted by Jeza

I also find it amusing that we don't stop to check something immediately after we hear a thump or feel something go odd.....

how true, i don't know. :shrug:

but its something that i hope won't happen again.