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small cracks on rotor ?

  • Thread starter Thread starter feifong
  • Start date Start date Dec 13, 2005

feifong

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Apr 4, 2005
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mesa
Dec 13, 2005
#1
  • Dec 13, 2005
  • #1
my rotor has small little lines that look like cracks going downward could this be why my rotors have tension on them when i spin em? are these bad?
 

Busted07

I need my gorilla to be about an inch longer.
Nov 15, 2005
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3
0
Dec 13, 2005
#2
  • Dec 13, 2005
  • #2
those are probably heat/stress cracks. your rotors are probably warped. if they have decent meat on them, see if they can turn them past the cracks and make them true again, if not, plan on buying new ones
 

old_blue

15 Year Member
Nov 3, 2003
1,783
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124
Dec 13, 2005
#3
  • Dec 13, 2005
  • #3
are they crossed drilled or regular rotors? either way they got over heated or might be a faulty rotor. do as said above. try and get them turned pass the cracking and to where they are true. good luck
 

srothfuss

Last night I stabbed the same guy 7 times in a row
Oct 17, 2004
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Woodward Ave.
Dec 13, 2005
#4
  • Dec 13, 2005
  • #4
New rotors are in order!
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,179
17,884
224
Massachusetts
Dec 13, 2005
#5
  • Dec 13, 2005
  • #5
feifong said:
my rotor has small little lines that look like cracks going downward could this be why my rotors have tension on them when i spin em? are these bad?
Click to expand...

I'm willing to be the cracks ont he rotors are the cause of another problem, and not the source for why they won't spin when you turn them.

Sounds to me like either your calipers pistons are frozen or your caliper slide pins are seized. I'd look into that before slapping on new rotors.

The heat from a constantly applied brake can heat the rotors up and cause the cracks.
 

srothfuss

Last night I stabbed the same guy 7 times in a row
Oct 17, 2004
1,796
3
0
Woodward Ave.
Dec 13, 2005
#6
  • Dec 13, 2005
  • #6
Mustang5L5 said:
Sounds to me like either your calipers pistons are frozen or your caliper slide pins are seized. I'd look into that before slapping on new rotors.

The heat from a constantly applied brake can heat the rotors up and cause the cracks.
Click to expand...


There is too much heat being generated for some reason. That we both agree on. I think it could be from 1 long hard stop @ the threashold of lock up.

If the rotors are cracked, I would replace them instead of turning them, but that is just me...
 

feifong

New Member
Apr 4, 2005
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mesa
Dec 14, 2005
#7
  • Dec 14, 2005
  • #7
replaced rotors does the same thing. When i tighted the caliper bolts all the way the rotor doesnt spin freely but seizes up these are new caliper bolts, so im running it with loose caliper bolts to let it spin. I had it checked somewhere Had it alighned and the new rotor has play on it up and down as if the bearings are messed up but they are new. The mechanic said the spindle i used was bent could this be why it doesnt spin ? Thanks
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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129
Dec 14, 2005
#8
  • Dec 14, 2005
  • #8
Did you replace the slide pins? They have a sacrificial coating that wears off after some time.

Or they are bent, like Mike said. NO way would I drive a car with loose mounting pins. You gotta get that fixed before driving it IMHO.

Good luck.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,179
17,884
224
Massachusetts
Dec 14, 2005
#9
  • Dec 14, 2005
  • #9
feifong said:
replaced rotors does the same thing. When i tighted the caliper bolts all the way the rotor doesnt spin freely but seizes up these are new caliper bolts, so im running it with loose caliper bolts to let it spin. I had it checked somewhere Had it alighned and the new rotor has play on it up and down as if the bearings are messed up but they are new. The mechanic said the spindle i used was bent could this be why it doesnt spin ? Thanks
Click to expand...

Rotors are not supposed to have ANY play in them up or down. They should not move period once attached to the spindle.

Does the rotor spin fine without the caliper on? If it does then the issue lies in the caliper or thetwo caliper pins.

First issue to tackle is why is there so much play in the rotor. Make sure the bearings are installed correctly. AGain, ZERO play in the rotor. It should only spin

Second is what is grabbing the rotor preventing it from spinning. Can the caliper pistons be pressed in? If so, press them in with the C-clamp, then reattach the caliper with the pads in place and press the brakes hard, then release and try to spin the rotor. The pistons should eventually wobble off enough clearance that the rotor should spin with light resistance.

Do not drive the car. Last thing you want is the wheel falling off.
 

powertrax91

Founding Member
Mar 13, 2002
598
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17
New York
Dec 14, 2005
#10
  • Dec 14, 2005
  • #10
feifong said:
The mechanic said the spindle i used was bent could this be why it doesnt spin ? Thanks
Click to expand...

that's your problem... when the mounting/slide bolts are tight the caliper is out of alignment causing the pads to make contact with the rotor
 
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