Mazda Rotary Club

Cars by Model Type => 2nd generation RX-7's => Topic started by: grinder on June 01, 2013, 12:59:29 PM

Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: grinder on June 01, 2013, 12:59:29 PM
Hiya

Thought i would try and get the brakes sorted on my white cab ( they arent the best i have to admit - and Mr MOT man says they needed doing )

so , car on a axle stand , wheel off , pads out ( one nearly down to metal so this wont be helping ) , caliper off ( wow , that took some unbolting )

And then the fun starts ( well , its not fun hence this post )

I have the disc loose , i can move it around a few MM so its not locked onto the front hub , but for the life of me , i cant get the thing off

I thought i might have a bent studd , but the new disc fits over the studds just fine - so i dont think its that

It just wont actually come off the car

I have hit with a mallet , hammer and lump hammer

Its like its stuck on something , but i cant see what ??

Any idea how i can pry the thing off ??

I dont have a disc puller .. so need something that i can find in the garage :D

Brett has suggested getting some heat onto it

Thats leaves me with "where do you apply the heat" , and also i though that was mainly if it was stuck on the hub - which it isnt

Please help :D :D

Stu
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: wolfie1 on June 01, 2013, 03:58:32 PM
You need to hit it with a hammer rotate the disc180 degrees then hit if off somemore, keep doing that till it comes off
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: L18M on June 01, 2013, 05:47:47 PM
bit of a silly thing but theres 1 or maybe 2 phillips screws holding the disc to the hub (was on mine) had to use an impact screw thing to get loose.

if you heat it then heat the outer sides of the disk as that should expand it. dont need to heat the face of the disk where the wheel touches the surface.
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: grinder on June 01, 2013, 07:39:36 PM
i forgot to mention that i have removed the 2 locating screws .. they came off dead easy which was a pleasant surprise .. last time i did this on the JDM cab , i had to drill them out

I have spent ages with the hit , rotate , hit , rotate method and its just not coming off :(

Like i said , there is play in it , so its not stuck to the hub .. its like there is something else stopping it .. but i cant see / feel it , its just ..... STUCK

Im tempted to try the heating it method tomorrow , and if that fails , looks like i might have to take the studs out , which i really dont fancy doing :(

When im doing the rotate / hit method , its like the disc moves at 45 degrees so it moves forward , but the other side then goes back intowards the car .. so its not coming of square

It doesnt help that i cant give it a big enough "whack" due to the caliper hanging in the way and the metal plate that sits behind the disc ( the shield ) , and i cant remove that as it looks like you have to take the disc off to unbolt it ! LOL
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: cyman on June 01, 2013, 09:21:50 PM
I take it you have taken the caliper hanger off so its out of the way.

You say you hit one side and the other side drops backwards.  What you may need to do is get one side out maybe half as far as it can travel then wedge something behind it so it cant drop backwards then hit the other side so it actually moves forwards and doesnt twist.

There shouldnt be anything else holdjng it bu maybe you are moving each side out to far and its locking ont the hub. It really is a case of perseverance sometimes even move it a mm then rotate move it a mm rotate etc etc you just need to stop it dropping backwards on the opposite side.
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: wolfie1 on June 02, 2013, 12:46:14 AM
Quote from: grinder;858776i forgot to mention that i have removed the 2 locating screws .. they came off dead easy which was a pleasant surprise .. last time i did this on the JDM cab , i had to drill them out

I have spent ages with the hit , rotate , hit , rotate method and its just not coming off :(

Like i said , there is play in it , so its not stuck to the hub .. its like there is something else stopping it .. but i cant see / feel it , its just ..... STUCK

Im tempted to try the heating it method tomorrow , and if that fails , looks like i might have to take the studs out , which i really dont fancy doing :(

When im doing the rotate / hit method , its like the disc moves at 45 degrees so it moves forward , but the other side then goes back intowards the car .. so its not coming of square

It doesnt help that i cant give it a big enough "whack" due to the caliper hanging in the way and the metal plate that sits behind the disc ( the shield ) , and i cant remove that as it looks like you have to take the disc off to unbolt it ! LOL


Thats it your getting it, next time its at 45 degrees, pull the furthest out side towards you and hit the other side (low side ), it will come it will just be a rust build up on the disc catching on the hub
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: grinder on June 02, 2013, 09:18:34 AM
Quote from: wolfie1;858781Thats it your getting it, next time its at 45 degrees, pull the furthest out side towards you and hit the other side (low side ), it will come it will just be a rust build up on the disc catching on the hub

thats what i have been doing ;) still wont come off ...

and whats more annoying , with all the pulling , hammering etc.. i now have a sore back and 2 sore arms and a disc STILL on the car ! LOL

Im sure that i will get it off today ... then i can face the challenge of the other side ! LOL :D :D
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: clive on June 02, 2013, 11:04:28 AM
You must have moved it a little bit so soak it with penetrating oil and have a go at the other side.

All the advise above is great you have been given already so all I can add as a worse case is tap all the studs out and the this way it can only be tight on  the centre spigot

hope this helps
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: grinder on June 02, 2013, 01:58:27 PM
like i have said in prev posts clive , its loose on the hub

So i have no idea what its stuck on

I dont know if the studs are screwed in or a press fit ?? As they "could" be the next to be removed :(
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: Prof on June 02, 2013, 04:39:12 PM
Are the studs bent in ever so slightly ?
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: grinder on June 02, 2013, 06:22:48 PM
Right , bit of an update ..

For starters , you were all wrong with your ideas :D

BUT , thanks for the info

Called in Dad for assistance .. he doesnt really know cars , but his he knows his stuff

I would have NEVER removed the disc by hammering it off

The disc had a large build up of rust on the back , it wouldnt come over the hub

So after messing for an hour trying to get the rust off the inside of the disc , my dad resorted to extreme measures .. thats right , off with the hub

Anyways , hub and disc off , hammer and chisel used to break off the rust and we finally got it off :D :D

I have some pics , so dont worry :D :D

What im left with now .. what disc do i put on ??

I have 2 discs , that arent marked with left or right etc.. , so i have taken pics of both discs on the hub , can some clever person tell me which one i need to bolt on please ( this is the drivers side front wheel )

And here are the pics :D
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: Brett on June 02, 2013, 08:37:10 PM
Disc two I reckon...

What state is the hub in?

Glad you got it off :D
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: grinder on June 02, 2013, 09:09:10 PM
actually the hub is OK , so thats good news

Just need to work out which disc to fit ?!?!?
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: grinder on June 03, 2013, 09:06:45 PM
OK , decided to crack on this evening

So back to the car armed with tools

Started to push the pistons back in the caliper , 3 of them were OK , the 4th just wouldnt move , and i mean it was STUCK

Even with a massive G-Clamp , i couldnt shift it

So i took the plunge , disconnected the brake hoses ( means i can fit the braided lines i have ) and off to my dads ( my garage is like a bomb site at the mo )

Showed it my dad , and he said we can blow them out with compressed air ( like the manual says ) .. errr NOPE

125 psi and we couldnt shift it

We couldnt even get the piston to rotate

So sort of deamed that it was shot and i needed a new caliper

So as i was leaving , my dad said "if you really want it out " .. errr yes please

Bring on the stiltsons ( of how ever you spell it ) , and not the small ones .. nah , the 2 foot ones

We manged to mangle the piston to hell and back but finally got it out .. looks like 1-2mm of rust on the piston can make a whole load of pain

This is prob down to the pads being down to 2MM on that side and the pistons being pretty far out

Anyways , all the pistons and seals are out , so i either need a rebuild kit ( if they come with what i need ) or a caliper ( and this is all on one side , i have NO idea what the other side is like )

This is turning into a massive job :(
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: wolfie1 on June 03, 2013, 09:23:57 PM
I did say it was rust build up holding it on? ;) On your 2 pics the left hand pic is the drivers side disc
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: grinder on June 03, 2013, 11:04:51 PM
OK mate , looks like you were right , i thought you meant the disc stuck on the hub .. not build up on the inside of the disc :)
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: Grieve on June 03, 2013, 11:53:29 PM
This thread is not what I wanted to see this week, was planning on changing all my discs, pads, lines and rebuilding the calipers this weekend...! Haha. Glad you\'re getting sorted though!
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: shaunwil on June 04, 2013, 07:28:44 AM
The car has sat for some time though !

Good to hear you got to thing off though. You should be able to get a rebuild kit. I\'m sure at a stretch Rock Auto sell rebuild kits for stock calipers.

Shaun
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: grinder on June 04, 2013, 07:30:06 AM
its turning into a real pain in the rear to be honest ...BUT .. once I have eventually finished they should be right for a few years ?!?!
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: Prof on June 04, 2013, 07:45:40 AM
Stu - I\'ll have to find it - but I\'ve got my pistons that I ordered for a rebuild - can\'t remember if I ordered 2 or 3, but I could let you have 1 for a sensible price - I\'ll even throw in some Red Rubber grease that you\'ll neeed to rebuild the brake caliper with, so you\'ll just need the sealing rubbers, springs and dust boots that you get in the standard rebuild kit.
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: Arnie_O on June 04, 2013, 02:02:05 PM
I am New to the FC so it\'s all info for me but having cooked the rear caliper on the way to its MOT it started leading fluid.
Called Lenny Carlof (Jim) he told me about Bigg Red (UK based) they do rebuild kits and mat have what you need.
I ordered a rear calliper rebuild kit (enough to do both rears seals) but no pistons for £28 delivered ... Is this classed as Grinder Price?not sure if you heard of them so posted this anyway... They also have listings on eBay
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: Prof on June 04, 2013, 03:37:19 PM
I think if you call big red they can get the pistons too, but the rebuild kits are normally just piston seal rings, springs and dust boots, some kits offer the bleed valve too - which is well worth replacing if it\'s got a bit flatted off.
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: Prof on June 04, 2013, 03:40:22 PM
It\'s worth noting that the bottom inside (I think) piston is suseptible to rusting as that\'s where water that\'s absorbed in to the brake fluid will collect.  As good a reason as any to do regular flushes of the brake system (every year or two).
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: Arnie_O on June 04, 2013, 05:06:45 PM
I did look earlier and they had rear pistons available... As as Prof says they probably can get fronts if they don\'t stock them.
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: grinder on June 04, 2013, 07:20:06 PM
might have found me a set of cheap FD calipers , so thinking of going down this route :D
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: Kodiak on June 05, 2013, 02:46:44 PM
Reading a comparision in a magazine and it stated that the stock variations of RX7 (FC&D) were actually some of the best out at the time amongst other older Jap metal.
 
As were their injectors.
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: Grant Monkhouse on June 05, 2013, 03:28:39 PM
2 days to make the scissor to remove the hub!! That\'s what I would have told you to do if the disk was sticking, my bad for being late onto the thread:(

I would send the calipers off for recon whether you use the fc ones or try the fd ones, just for the knowledge that they will have been done correctly.

If the rust was so bad to get the disc off I would also get new hubs, they won\'t need renewing for a log time and they will be rust free.

I understand you don\'t like to spend cash but these parts are the only thing that stop your so well worth the small expense
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: grinder on June 05, 2013, 11:12:12 PM
Hubs are ally so they are fine
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: JohnC on June 05, 2013, 11:45:24 PM
Using FD calipers?

Are they the same? Or and upgrade?

If they are an upgrade, do the stock size FC discs and pads work?
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: JohnC on June 05, 2013, 11:57:00 PM
Never mind. Found my answer from the Interchangable parts for FC.

I\'ll be taking a few bits from my mate\'s FD(calipers, master cylinder, diff) :)

Yoink!
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: aundre-3000 on July 03, 2013, 11:56:06 PM
Must be a fc thing midway down in my thread I had the same problem

http://www.mazdarotaryclub.com/forums/showthread.php?t=73021&page=2
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: grinder on July 04, 2013, 07:50:17 PM
seeing as I picked up some calipers , thought it would be a good idea to paint them

Im going with a white/blue theme on the car , so blue seemed the best choice

ive only done the drivers side at the mo , but the 2 pics are the original and then with one coat of smoothrite
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: shaunwil on July 04, 2013, 08:27:51 PM
Nice colour !

Shaun
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: grinder on July 06, 2013, 10:53:20 AM
should have given it another coat really .. had a closer look in the garage and its not covered 100% , there are still some "thin" bits of paint

But once its on and hidden behind a wheel , I reckon it should "look" OK :D
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: grinder on July 06, 2013, 07:46:03 PM
doesn\'t look tooo bad fitted I suppose

Put it on with a braided hose aswell , so that should be OK for the future

Used a vac pump bleeding kit that I borrowed , makes bleeding the brakes a 5 min job

Started on the other side , disc wouldn\'t come off , so rather than playing around , off with the hub and did it that way

Prob took about 20 mins rather than XX hrs

So need to paint the other caliper and then get it all back on the car

MOT expired today , so cant even test what I have done on the road .. it will be tested on the way to the MOT station in a few weeks when I have finished and booked it in :D
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: Prof on July 07, 2013, 08:31:24 AM
Looking good Stu.

Little tip - I used some Ceramic spray stuff (it\'s a lubricant and water repellent) on the hub so that the hub to disc surface was covered.  It makes getting brake discs off a doddle in the future ;-)  Also, being Ceramic it doesn\'t cook off when the brakes get hot, nor will it slip into the brake surfaces.
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: grinder on July 07, 2013, 08:10:46 PM
to be honest , when I took them off the JDM they nearly fell off , so no idea why this is so bad

Not sure if the JDM one was a jap and therefore less rain ?? or because that one had half the milage

But in the grand scheme of things .. these discs wont be coming off again !
Title: Advice needed with front disc removal ( goes from bad to worse )
Post by: shaunwil on July 07, 2013, 09:37:49 PM
Good chance it hadn\'t sat for as long ! Plus they don\'t use salt like the uk does in winter.

Shaun