I have checked rotor runout
Thread Starter
Racer
Joined: Jan 2014
Posts: 407
Likes: 14
From: Mulberry Florida
I have checked rotor runout
I picked up dial indicator this morning from harbor freight, and checked front and rear. The rear was about 0.003 to 0.004, the left front was around 0.006, and right at 0.004. Question is the rotors have been removed before I bought the car, and if they did not put them on the way they came off could that be the reason run out is off. This may be a stupid question. I hope that by pulling the rotors off and rotating one hole at a time until I can get a better reading will fix the problem, or at least get it closer to where it was before they removed them.
Thanks for the help
Larry
Thanks for the help
Larry
2026 Loser of the Year
Joined: Sep 2013
Posts: 36,600
Likes: 7,046
From: New Or-leens Loo-z-anna
Those numbers really aren't that bad/.006" max. for rotors that have been removed previously!
Maybe there is some paint/rust/dirt that is on the hubs or the inside faces of the rotors.
Check the runout on each hub first and write the readings on the hubs to determine if they are causing the runout.
You probably know that you don't need to reinstall the wheels each time you index the rotors.....instead just torque the rotrs down with the lugnuts and recheck the runout. Use a torque wrench to make sure the rotors tighten evenly.
Maybe there is some paint/rust/dirt that is on the hubs or the inside faces of the rotors.
Check the runout on each hub first and write the readings on the hubs to determine if they are causing the runout.
You probably know that you don't need to reinstall the wheels each time you index the rotors.....instead just torque the rotrs down with the lugnuts and recheck the runout. Use a torque wrench to make sure the rotors tighten evenly.
Melting Slicks
Joined: Apr 2007
Posts: 3,189
Likes: 111
From: Tolland CT
I picked up dial indicator this morning from harbor freight, and checked front and rear. The rear was about 0.003 to 0.004, the left front was around 0.006, and right at 0.004. Question is the rotors have been removed before I bought the car, and if they did not put them on the way they came off could that be the reason run out is off. This may be a stupid question. I hope that by pulling the rotors off and rotating one hole at a time until I can get a better reading will fix the problem, or at least get it closer to where it was before they removed them.
Thanks for the help
Larry
Thanks for the help
Larry
Another option may be to buy a shim from NAPA. They list a shim which offsets the rotor to counter the run out.
2026 Loser of the Year
Joined: Sep 2013
Posts: 36,600
Likes: 7,046
From: New Or-leens Loo-z-anna
If you're talking about the rear rotors, I believe there is only one way they can be installed and have the hole for parking brake adjustment line up. Going from memory. I found I could get a better run out if I rotated by rotor but found the parking brake adjustment hole was off making adjustment impossible. You could drill a new hole if you really want to change the positioning of the rotor.
Another option may be to buy a shim from NAPA. They list a shim which offsets the rotor to counter the run out.
Another option may be to buy a shim from NAPA. They list a shim which offsets the rotor to counter the run out.
Pro
Joined: Jul 2006
Posts: 505
Likes: 25
From: Buxton Maine
I tapped the rivet holes in the hubs 3/8-24, Then Countersunk the rotors to accept a flat socket head cap screw 5/8" long. The cap screws take the place of the rivets and are removable. This way you can shim and re-check until you get it. Got this idea from Gary Ramadei. It works great. Rick
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
I picked up dial indicator this morning from harbor freight, and checked front and rear. The rear was about 0.003 to 0.004, the left front was around 0.006, and right at 0.004. Question is the rotors have been removed before I bought the car, and if they did not put them on the way they came off could that be the reason run out is off. This may be a stupid question. I hope that by pulling the rotors off and rotating one hole at a time until I can get a better reading will fix the problem, or at least get it closer to where it was before they removed them.
Thanks for the help
Larry
Thanks for the help
Larry
2026 Loser of the Year
Joined: Sep 2013
Posts: 36,600
Likes: 7,046
From: New Or-leens Loo-z-anna
I tapped the rivet holes in the hubs 3/8-24, Then Countersunk the rotors to accept a flat socket head cap screw 5/8" long. The cap screws take the place of the rivets and are removable. This way you can shim and re-check until you get it. Got this idea from Gary Ramadei. It works great. Rick
Melting Slicks
Joined: Oct 2011
Posts: 3,453
Likes: 67
From: Midland Ontario
NCM Sinkhole Donor
Those numbers really aren't that bad/.006" max. for rotors that have been removed previously!
Maybe there is some paint/rust/dirt that is on the hubs or the inside faces of the rotors.
Check the runout on each hub first and write the readings on the hubs to determine if they are causing the runout.
You probably know that you don't need to reinstall the wheels each time you index the rotors.....instead just torque the rotrs down with the lugnuts and recheck the runout. Use a torque wrench to make sure the rotors tighten evenly.
Maybe there is some paint/rust/dirt that is on the hubs or the inside faces of the rotors.
Check the runout on each hub first and write the readings on the hubs to determine if they are causing the runout.
You probably know that you don't need to reinstall the wheels each time you index the rotors.....instead just torque the rotrs down with the lugnuts and recheck the runout. Use a torque wrench to make sure the rotors tighten evenly.
I'm with Gunner here. I used a brass brush on my cordless drill to take the hub and back of the rotors down to nice clean metal. Check the rotor first as everything relies on this being as true as possible. If you're this far in, indexing all four corners to get the best reading won't take more than an hour or so. Once your confident with these measurements, move on to rubber lines and caliper seals, then master cylinder.
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Thread Starter
Racer
Joined: Jan 2014
Posts: 407
Likes: 14
From: Mulberry Florida
Thanks all I will take all of you all advice and see how it comes out. I have a big car show this coming weekend in Plant City, Fl. I will let everyone know how it comes out.
Thanks for the help!
This forum is the best
I would like to take a minute to say Happy Birthday to all marines.
Semper Fi
Larry
Thanks for the help!
This forum is the best
I would like to take a minute to say Happy Birthday to all marines.
Semper Fi
Larry
Burning Brakes
Joined: Oct 2013
Posts: 992
Likes: 28
From: Sutton MA
When I did my fronts .005 was the limit. And I remember I marked a stud and the rotor, so I had a starting point, then I would move that mark one stud at a time, measuring run out each stud. The interesting thing was, all other studs, other than the correct one was WAY off, I mean not even close, then when I was on the right one, bingo!
I then used some of the misses neon nail polish to mark a stud, and a corresponding spot on the rotor for future reference.
I then used some of the misses neon nail polish to mark a stud, and a corresponding spot on the rotor for future reference.
Thread Starter
Racer
Joined: Jan 2014
Posts: 407
Likes: 14
From: Mulberry Florida
When I did my fronts .005 was the limit. And I remember I marked a stud and the rotor, so I had a starting point, then I would move that mark one stud at a time, measuring run out each stud. The interesting thing was, all other studs, other than the correct one was WAY off, I mean not even close, then when I was on the right one, bingo!
I then used some of the misses neon nail polish to mark a stud, and a corresponding spot on the rotor for future reference.
I then used some of the misses neon nail polish to mark a stud, and a corresponding spot on the rotor for future reference.
Thanks again!
Larry
Burning Brakes
Joined: Oct 2013
Posts: 992
Likes: 28
From: Sutton MA
I've been warned about the backs, I haven't ventured back there yet
Thread Starter
Racer
Joined: Jan 2014
Posts: 407
Likes: 14
From: Mulberry Florida
I forgot to add, I used a different color on each side, so as to not confuse them if they come off again. Because I didn't know anything about run out, so I had to do twice the work when putting them back on.
I've been warned about the backs, I haven't ventured back there yet
I've been warned about the backs, I haven't ventured back there yet
Thanks again! Larry
2026 Loser of the Year
Joined: Sep 2013
Posts: 36,600
Likes: 7,046
From: New Or-leens Loo-z-anna
That is what is needed on mine, trailing arm bushing, emergency brake rebuild, shocks, and other. The problem is if I get down to do the work I need a crane to get back up. I have notice here on the forum, there must be a lot of rich people to be able to do as much on there cars as they do. I'm not in that boat.
Thanks again! Larry
Thanks again! Larry
Yes there are $$$$$$$$$$$ members (annnnnnnd I'm jealous!)
But on the other hand.......I rebuilt everything that has been rebuilt thanks to the other Forum members....I also have always carried a compact floor jack and tool box in all my vehicles while on the road in one of them.....yes it's 50 extra pounds, but I'm going on a diet to offset it
So.....should a trailing arm bearing begin to fail....I limp to the nearest parts store...........and rebuild the trailing arm.....annnnnd drive on!
So....some members are blessed to be able to pay to have work done next week.....and others of us only need a parking lot for a few hours.