Lotus Elan

Rear brake caliper problems

PostPost by: thorbs000 » Tue Feb 11, 2014 10:47 am

Hi all
After installing a new cv driveshaft to my 68 +2 at w/e along with a new disc,I have come to put the caliper back on. When I attempt to tighten the two bolts holding it on,the position of the caliper in relationship to the disc,the disc is not central to the gap in the caliper and locks the disc up.
Nothing on the hub has been disturbed and it didn't do this before.
I have tried putting the old disc back on and it does the same and locks up the disc.
I can get round the problem by putting a 1/8 washer between the caliper and the flange it fastens to on the hub but I wouldn't think you should have to do that
Anybody out there had a similar problem

Thanks again
Ian
Attachments
image.jpg and
thorbs000
First Gear
First Gear
 
Posts: 37
Joined: 14 Mar 2013
Location: Burnley, lancs

PostPost by: rgh0 » Tue Feb 11, 2014 12:16 pm

If it worked before it should work now without needing a washer to space it. There must be some change in its assembly. Have you got the disk on the outside of the three eared driveshaft connection and the calliper on the inside of the lugs on the alloy hub carrier?

cheers
Rohan
User avatar
rgh0
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 7487
Joined: 22 Sep 2003
Location: Melbourne, Australia

PostPost by: robertverhey » Tue Feb 11, 2014 1:11 pm

Only way I could see this happening is if there's been relative movement between the outer shafts and the hub carrier. Are your circlips still all in place?
robertverhey
Fourth Gear
Fourth Gear
 
Posts: 781
Joined: 20 Feb 2007
Location: Sydney Australia

PostPost by: rgh0 » Tue Feb 11, 2014 1:17 pm

I think it happens if you mount the disk on the inside on the hub shaft arms rather than the outside but reverse its dish orientation from the correct way

cheers
Rohan
User avatar
rgh0
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 7487
Joined: 22 Sep 2003
Location: Melbourne, Australia

PostPost by: thorbs000 » Tue Feb 11, 2014 3:29 pm

Thanks for all your advice. I do think I have the disc on the correct way and the caliper mounted correctly.
As I said, the hub has not been touched and this is what I can't understand.
thorbs000
First Gear
First Gear
 
Posts: 37
Joined: 14 Mar 2013
Location: Burnley, lancs

PostPost by: Craven » Tue Feb 11, 2014 4:28 pm

Hi,
Do the old pads show signs of a previous offset.
Craven
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1072
Joined: 14 Sep 2013
Location: south coast uk

PostPost by: rgh0 » Tue Feb 11, 2014 11:11 pm

show some more photos of the assembly from other angles. That may give some clues to whats going on

cheers
Rohan
User avatar
rgh0
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 7487
Joined: 22 Sep 2003
Location: Melbourne, Australia

PostPost by: Quart Meg Miles » Tue Feb 11, 2014 11:29 pm

rgh0 wrote:I think it happens if you mount the disk on the inside on the hub shaft arms rather than the outside but reverse its dish orientation from the correct way

cheers
Rohan

I suspect Rohan is correct. The centre of the disk mounts on the wheel side of the output shaft spider with the disc face itself facing back towards the diff and overhanging the UJ. Its location is not affected by anything else in the drive line so if it lined up before it must line up now. I've changed wheel bearings several times as well as doughnuts and have never had your problem.
Meg

26/4088 1965 S1½ Old and scruffy but in perfect working order; the car too.
________________Put your money where your mouse is, click on "Support LotusElan.net" below.
User avatar
Quart Meg Miles
Fourth Gear
Fourth Gear
 
Posts: 983
Joined: 03 Oct 2012
Location: Barnham, W Sussex, UK

PostPost by: thorbs000 » Wed Feb 12, 2014 9:58 am

Hi everybody

This is now doing my head in. Been in the garage and decided to strip the rear of driveshaft,caliper and disc and start again.
I have put the disc on with some short nuts and bolts and taken photos.
Then took off disc and put caliper on,again photos taken.
Next,remove caliper and replace disc and caliper together. Guess what,disc is still binding on the inner side of the caliper. Argggggggggg
Rethink time.
I know, put the other side together and see what happens. Perfect,disc is in center of caliper and runs free.
WHATS WRONG!!!!!!!!!!!!!
I have taken photos from different angles as suggested.

Thanks
Keeping my fingers crossed that someone can help

Ian
Attachments
image.jpg and
image.jpg and
image.jpg and
image.jpg and
image.jpg and
image.jpg and
image.jpg and
thorbs000
First Gear
First Gear
 
Posts: 37
Joined: 14 Mar 2013
Location: Burnley, lancs

PostPost by: rgh0 » Wed Feb 12, 2014 11:02 am

Cant see anything obviously wrong in the photos but if you have one side that works and one that does not the rest should be easy - just find the difference !

cheers
Rohan
User avatar
rgh0
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 7487
Joined: 22 Sep 2003
Location: Melbourne, Australia

PostPost by: tonyr27 » Wed Feb 12, 2014 11:10 am

Everything looks ok to me too.

As it's a new brake disc, I would now check thickness of its mounting flange along with its position against the original disc or the one that's ok on the opposite side.

Good luck

TonyR
1968 Plus 2 Cirrus White
1966 S3 FHC Medici Blue
tonyr27
Second Gear
Second Gear
 
Posts: 150
Joined: 02 Sep 2013
Location: South Yorkshire

PostPost by: robertverhey » Wed Feb 12, 2014 11:25 am

Swap the discs? One of them may be faulty. See if the problem travels with the disc
robertverhey
Fourth Gear
Fourth Gear
 
Posts: 781
Joined: 20 Feb 2007
Location: Sydney Australia

PostPost by: john.p.clegg » Wed Feb 12, 2014 12:07 pm

Measure the offset? Compare with your old one..

John :wink:
User avatar
john.p.clegg
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 5682
Joined: 21 Sep 2003
Location: Manchester

PostPost by: billwill » Wed Feb 12, 2014 12:27 pm

You missed out one obvious test.

With the shaft disconnected from the disc/hub, but with the disc mounted with your short bolts, refit the caliper to see if it is still offset.

This wil eliminate the shaft as a cause of the problem.

Re-reading... perhaps you did that ?

~~~~~~~~~~~

You bought new discs, but did you buy new pads? Try swapping over the pads from the other side of the car, using all possible combinations.
Bill Williams

36/6725 S3 Coupe OGU108E Yellow over Black.
billwill
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 4717
Joined: 19 Apr 2008
Location: London UK

PostPost by: Craven » Wed Feb 12, 2014 1:32 pm

Hi,
What is different, checking any old parts you have may point back to the previous set up.
Discs not in centre of a caliper is not unknown, maybe some packing shims fell out unnoticed on disassembly, any unusual registration marks on mounting points.
Craven
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1072
Joined: 14 Sep 2013
Location: south coast uk
Next

Total Online:

Users browsing this forum: No registered users and 13 guests