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Changing hr brake rotors

Posted: Sat Jan 23, 2010 9:52 pm
by jake08
Someone already started a post with the same question but i can't find it.

I am trying to remove the old rotors but the crosstip screws that hold the rotor to the hub wont budge. I bought the biggest phillips torquemaster i could find and fitted a ring spanner on it but had to stop before I rounded the screws.
Tried a battery impact driver but same problem.
Soaked the screws from the head end with WD40 everyday for a week before trying again- same result.
Removed hub from stub and soaked screws from tail end daily for another week- same result.
Does anyone know if I can get a larger crosstip for the impact driver or have any ideas?
Normally any idiot can pull a car apart but I've been stalled already!!! :evil:

Posted: Sat Jan 23, 2010 10:01 pm
by jake08
just in case my explanation wasn't clear enough
Image



Image

Posted: Sat Jan 23, 2010 10:24 pm
by rosco
Hi Jake,
I went through this about four years back - was petrified I was going to either break one of the studs off or (worse) strip the slots of the screw heads.

I cannot stress highly enough that you NEED a perfect fit impact bit for those studs - anything else will most likely chew out the heads......
I found those bits in the Kinchrome impact driver set (blue metallic box with impact driver)..... ended up having to purchase two of them...... read on........

I tried WD-40, heat, impact driver (hammer type.... broke quite a number of Kinchrome impact driver bits in the process) completely smashed the head of the first Kinchrome impact driver with hammering from a short handled sledge hammer........simply gave up for a while whilst I "pondered" on it......

I ended up going to the extreme of purchasing an air driven impact driver.
Soaked the heads/threads again. removed the rotors/hubs from the stub axle and laid it flat - rotor down on plate steel - first attempt didn't budge anything - second attempt I wound up the compressor to 120 psi and "sat" on the top of the impact driver.... by now I was prepared to suffer any loss...

It took quite some time, but once the first stud started to move, I knew I was going the right way..... got all ten studs out in this fashion -.... with rotor/hub/impact driver and me turning in different directions on the floor of the garage - mine had been in there since d1965 (yes HD disc brake) ..... but they did come out....

Now - the good news - you can still get new RDA rotors to refit....
AND you can purchase hex headed high tensile counter-sunk bolt sets to re-fit them... you'll need the driver head as well...... I purchased mine from Rares.

I put some loctite 262 on the threads this time so that in the unlikely event I ever have to go through this again...... it won't be such an issue.

When I fitted mine, I progressively torqued them up every second stud until I had them all at spec..... can't remember what the good book says - but will post if required.
I punched marks into the hubs to keep check on the studs..... they haven't moved since being fitted....

Let us know how you get on....

ps - I didn't pay an awful lot for the air impact driver - probably about the same as the two sets of Kinchrome bits I wrecked......

frats,
Rosco

Posted: Sat Jan 23, 2010 10:46 pm
by jake08
Thanks for the reply Rosco- might have to look for a bigger driver- the correct impact bit you got in a set right?

Posted: Sat Jan 23, 2010 10:56 pm
by rosco
Yes, Jake - think it came from Bursons -

Kinchrome set - blue metallic painted tin 6" long by 2" wide.....
Has about a dozen assorted impact bits and the heavy driver assembly...

Think each set was around $20 - 25......

I would certainly suggest to place the rotors/hubs on a solid flat surface before working them out with an impact driver..... do NOT do this on the bearings or whilst fitted to the vehicle.... but you know this.....

Can chase up my logbook and give you a parts number for the driver set if you need it.....

frats,
Rosco

Posted: Sun Jan 24, 2010 12:38 pm
by mrs ratbox
i had some removed that looked much worse than yors, what we used was a big well fitting screwdriver (bigger head/tip than the one you have) but the shaft went through the handle so you could belt it with a hammer then put a shifter or spanner on the end and undo it
i'm sure there prolly is a technical name for this typr of screw driver but i don't know it :oops: :)

Posted: Sun Jan 24, 2010 1:23 pm
by Trev
Take it to a mechanic and he will get the job done, I do this when I get really stuck, Trev 8) .

Posted: Sun Jan 24, 2010 2:16 pm
by FB MAD
Without reading the replys,

Get an old buggered screwdriver that has the full steel shaft right through the handle to the end and is is able to be whacked with a hammer.

Cut the screwdriver end off so it is flat faced.

Whack the screws with a couple of good hard whacks from a good sized hammer on a hard concrete floor and an old single sheet rag underneath.

This will do two things:-

It will temporarily repair the phillips slots if they have been slightly chewed out ( won't repair completely chewed out slots ) and the hard knocks will unfreeze the bind that the screw head metal has with the rotor metal.

Should then be able to either unscrew with an impact driver or sometimes even just with ordinary hand driven screwdriver pressure.

Hope that helps.

Posted: Mon Feb 01, 2010 10:13 pm
by jake08
Take it to a mechanic and he will get the job done, I do this when I get really stuck, Trev .
Generally not the way I prefer to go but-
went to an exhaust shop the other day and he was doing a pair hr calipers on his bench- 15 bucks! :shock:
All done 8)

Posted: Mon Feb 01, 2010 11:11 pm
by (AUST)Mod
Anyone know if you can get cross drilled or slotted rotors for a HR brake setup?

Posted: Mon Feb 01, 2010 11:52 pm
by mrs ratbox
jake08 wrote:
Take it to a mechanic and he will get the job done, I do this when I get really stuck, Trev .
Generally not the way I prefer to go but-
went to an exhaust shop the other day and he was doing a pair hr calipers on his bench- 15 bucks! :shock:
All done 8)
sometimes it's just not worth f#%king around with it yorself :wink: :lol:

Posted: Tue Feb 02, 2010 3:40 am
by Trev
ratbox wrote:
jake08 wrote:
Take it to a mechanic and he will get the job done, I do this when I get really stuck, Trev .
Generally not the way I prefer to go but-
went to an exhaust shop the other day and he was doing a pair hr calipers on his bench- 15 bucks! :shock:
All done 8)
sometimes it's just not worth f#%king around with it yorself :wink: :lol:
My point exactly :D

Posted: Tue Feb 02, 2010 8:00 am
by rosco
All done Jake - I'm just a little bit different to most others.... in fact probably almost others....

frats,
Rosco

Posted: Tue Feb 02, 2010 10:16 am
by dave68
(AUST)Mod wrote:Anyone know if you can get cross drilled or slotted rotors for a HR brake setup?
Yep just took a set off my bus yeaterday for the new uc ones. :wink: They are drilled and slotted. :wink:

Posted: Tue Feb 02, 2010 8:25 pm
by Craig
dave68 wrote:
(AUST)Mod wrote:Anyone know if you can get cross drilled or slotted rotors for a HR brake setup?
Yep just took a set off my bus yeaterday for the new uc ones. :wink: They are drilled and slotted. :wink:
Slotted are around $120 a rotor from memory apposed toaround $70 a rotor standard drilled would be dearer there would be bugger all difference in breaking would only be for wank factor unless you race it and Andrew you have a red so I wouldnt race it :wink:

best upgrade would be larger diameter ventilated disks if you are serious