New wheel studs and rotor runout - episode I

MYBAD79

MYBAD79

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In a galaxy far far away.......


OK .... I started the wheel stud and rotor runout project. I finally got the new drill press and ordered tools and bolts from McMaster.... the 3/8" bolts and the tap should be here tomorrow :)

Here's the new toy (260-3000rpm):
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I removed the rotor/hub assembly and drilled the rivets.
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This is the hub after I cleaned it. Not too shabby for 29 years....
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The rotor was riveted to the hub and there were no shims between the two parts, seems to be all NCRS correct..... should have sold it on Ebay for $5000 and buy a nice Wilwood setup....oh well.....
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This is the inside of the rotor after soaking it for an hour in NavalJelly.... that stuff really eats rust, just as advertized....
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These are the rivets:
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and a few close up pics:
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Tomorrow I'll tap the rivet holes 3/8"-24 and countersink the holes in the rotor, then bolt the rotor to the hub and drill 43/64" for the new 5/8" studs.

There were no shims between rotor and hub and I measured runout when it was still on the car.... less than .005".... not bad at all.....
 
All right.... here we go:

I found the two small recessed areas where one can place a punch to drive out the races. the races came out easy, for your entertainment I took a few more pics:

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I am still waiting for the 3/8"-24 tap, the countersink and the bolts..... more update hopefully tomorrow :thumbs:
 
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Made some progress:

I tapped the holes 3/8 -24 and countersunk the holes. I then bolted the rotor to the hub and drilled 43/64" for the new studs.

I pulled the studs in the holes using a nut and a few washers, was a lot easier than I thought.

Note that I had to grind a flat on the stud's collar so it wouldn't touch the radius on the back side of the hub.

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here's the flat spot (one of them, all studs need the flat spot):
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I also installed the new bearing races. I had them in the freezer for an hour while I ground the old races down. I ground the outer diameter of the old races so I could use them to tap the new races into the hole.... then left the hub outside in the sun so it got hot.... the FL sun is so hot I needed gloves to touch the hub....the cold new races went in easy, not much force needed, lightly tapped them in the hole.
 
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SmokinBBC said:
Nice job. Did you check runout b4 you bolted on the rotor? Or, you gonna check/adjust on the car?
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I wish i had a spare spindle so I can do the runout off the car.... I have to wait until I install the new bearings and mount the rotor/hub assembly on the spindle on the car.... The runout was good before I took it off, hopefully it's still good now that I cleaned the mating surfaces. I guess I'll see tomorrow.....
 
Did you try to remove the rotor afterwards? Any issues. I just did 1/2-20x3" and those were tricky as a slight taper in the stud install will add up over 3"
 
Gary,
no issues. I did not press the new studs in, I used a few washers and a nut to "pull" the stud into the hole. The washers are parallel (or at least almost parallel) so that dictates that the stud is perpendicular to the hub's mating surface.

I pulled the rotor off a few times to correct the runout. I found that there's only one way to mount the rotor, I should have marked the position before I drilled the rivets. The runout on both rotors is .003", however if you rotate the rotor and mount it two holes off (clockwise or counterclockwise) the runout is as bad as .011"

Now I have .003" max runout and no shims - perfect :smash:

I considered new rotors since mine are definitely original and 30 years old but then the runout will be worse.
 
Here's a photo of the new studs. I'll have to cut the unthreaded part off, I'll then cover it with the spinner cones :D:D:1st:

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Why not leave the quick start ends on and do away with the spinner...hell, get some new wheels for the car. :D It needs some nice 18s :)
 
Twin_Turbo said:
It needs some nice 18s :)
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I know... thanks for reminding me.... (Stewie voice): I hate you.....

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i thought special lugs were needed for those stock al wheels. Have you driven on the highway yet?

There has been much discussion over the years of stock al wheels shimmying when non stock lugs are used.


The initial picts of the rotor showed quite a bit of rust. How much rust was between the cooling vanes? If a lot it will affect cooling.

Why do you think a replacement rotor won't be true?
 
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turtlevette said:
i thought special lugs were needed for those stock al wheels. Have you driven on the highway yet?
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I countersunk the holes in the rims 90 degrees. All other aluminum rims that I own have a 90 degree countersunk for conical seat lug nuts so I'm sure that's not a problem.
I had it up to 65mph with no vibrations or wheels falling off my car. I'll continue testing once I have the battery charged and can start the damn thing... (another story).....

turtlevette said:
There has been much discussion over the years of stock al wheels shimmying when non stock lugs are used.
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The stock lug nuts have a sleeve that fits tight into the hole in the rim. If you use other lug nuts that don't fit as tight the rim can be misaligned or move slightly... one reason I believe in 90 degree tapered (conical) seats.

turtlevette said:
The initial picts of the rotor showed quite a bit of rust. How much rust was between the cooling vanes? If a lot it will affect cooling.
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Yes, there was quiet a bit of rust. I cleaned the inner diameter and the mating surfaces. I could not get in between the cooling fins - I have a benchtop sandblaster but I have not hooked it up yet. I'll take the rotors off one more time and blast them clean. I need to replace the brake pads anyways and get something better than the organic stuff.... semi metallic eats the rotor but that still takes 80000 or more miles....

turtlevette said:
Why do you think a replacement rotor won't be true?
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Because of all the shimming Gary does... my stock rotors were within .005" when I removed them and at .003" after I cleaned the mating surfaces and found the correct orientation.... rotating the rotors two holes over changes the runout to .010"... that proofs that they were indeed machined as a set... how can a new rotor possibly be running true ?
 
MYBAD79 said:
Because of all the shimming Gary does... my stock rotors were within .005" when I removed them and at .003" after I cleaned the mating surfaces and found the correct orientation.... rotating the rotors two holes over changes the runout to .010"... that proofs that they were indeed machined as a set... how can a new rotor possibly be running true ?
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I just put new rotors on and go. Don't do the A/R runout thing.

Its a lifestyle choice.:quote:

The wilwood calipers do not pump air.

with so much rust i don't see how runout can stay the same anyway. Water gets between the hub or spindle and rotor and moves it.

i buy off on everything else you said.
 
turtlevette said:
I just put new rotors on and go. Don't do the A/R runout thing.

Its a lifestyle choice.:quote:

The wilwood calipers do not pump air.

with so much rust i don't see how runout can stay the same anyway. Water gets between the hub or spindle and rotor and moves it.

i buy off on everything else you said.
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Actually there wasn't too much rust between rotor and hub, runout changed .002" from before and after cleaning the mating surfaces...from .005" to .003" ..
I was very surprised to see the runout at .012" when I accidentally mounted the rotor 2 holes off... should have marked the position....I had to unbolt it, remove and re-mount it three times until I found the correct orientation.

just for shitz and grinz.... get the dial indicator out and check the runout yourself, see if rotating the rotor relative to the hub makes a difference.... then we'll know....

I am actually shocked that I just destroyed a piece of NCRS correct material last weekend.... :tomato::tomato::tomato:
 
MYBAD79 said:
just for shitz and grinz.... get the dial indicator out and check the runout yourself, see if rotating the rotor relative to the hub makes a difference.... then we'll know....
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now do you REALLY think I would have a dial indicator?

yea, its right next to the clay bar and the expensive torque wrench.
 
I purchased a dial indicator to do the run out on my rotor's,but i do not have any shim material,or a drill press yet :search:. Since my front rotors still have the rivets in them do i need to check the runout on them? the rears i drilled out over the winter to rebuild the park brake,which bye the way works very good even on an incline :eek:

Oh where do you get the shims at ???????????
 
kwplot34 said:
I purchased a dial indicator to do the run out on my rotor's,but i do not have any shim material,or a drill press yet :search:. Since my front rotors still have the rivets in them do i need to check the runout on them? the rears i drilled out over the winter to rebuild the park brake,which bye the way works very good even on an incline :eek:

Oh where do you get the shims at ???????????
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Use the dial indicator to check the runout, mine was at .005 which isn't all that bad.... cleaning the mating surfaces (for the first time in 30 years) reduced runout to .003".

You don't need a drill press to drill the rivets, a handheld drill is just fine.

Index the rotor if you remove it from th hub so it goes back in the same orientation it came off.... saves a headache.....

If you do see your runout being excessive drill the rivets, clean the mating surfaces without removing material (metal) and see how bad or good the runout is then....
 
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