rear caliper overhaul

drabbers

Active Member
#81
I wonder if the 'access plates' story has been passed on incorrectly from (twin tank) IRS jags with inboard discs where on a rare occasion bodgers would supposedly cut holes for 'simple' access !

Mark
 
#82
Did both mine as pivot pin seized on one. Fitted new pads and discs. As car less than 34.000miles from new decided brakes were ok .reassembled. Passed mot but to be honest handbrake is next to useless. Luckily I have an auto so leaving in P plus handbrake? Seems to hold it on a small slope.
Not brave enough to try parking on a hill as sure handbrake isn't up to it even though adjusted so virtually no play.. Set up on rebuild for ratchet to operate etc.
Wondering if anybody has better system eg brakes of say a jag? Etc to replace p6 rear as at moment I prefer a brick on a piece of string.
 

harveyp6

Well-Known Member
#83
classicalgreen said:
Not brave enough to try parking on a hill as sure handbrake isn't up to it even though adjusted so virtually no play.. Set up on rebuild for ratchet to operate etc.
Something wrong there then, as if set up correctly, and with no slack in the cable I'd always have faith in the handbrake.
 
#84
I agree with Harvey, I've always found the handbrake to be exemplary if everything is adjusted and working correctly. Something must be amiss somewhere. I vaguely recall that if the mechanical "scissor" linkage is rusted solid you would get a very hard lever but only one calliper applied fully.

Yours
Vern
 

sdibbers

Well-Known Member
#85
Someone asked about getting a stubborn hydraulic piston out without compressed air a while back. I had that problem today. The cylinder is sleeved in stainless but the steel piston had rusted enough to swell and jam in the bore even with 150 psi from a bike pump.

I went to a motor factors found a grease nipple that fitted one of the brake line ports and a grease gun. I made sure the bleed nipple was closed and pumped grease in. The piston came out as easy as. I'm glad to say the cylinder walls were scratch free. Rebuild kits and new SS pistons from MGDB spares are on their way for the rebuild.

I hope that helps others.

Steven
 
#87
Hi Guys,
I'll make a quick introduction here as I've just joined the forum.
My names Mike Todd and I live in Tauranga, NZ.
I'm just bringing my 1973 3500S out of hibernation after 15 years off the road and will be working through all the issues this will throw up as time permits. It was only going to be off the road for a couple of weeks while I sorted a few things. I know I'm not the only one that this has happened to, as 3 of my mates have garage ornaments that they've owned for 20 years or more. I've been spurred into action as one of them is in danger of having his roadworthy soon and I think that with a bit of effort I could still beat him to have mine at least running.
I've owned it for the last 25 years.
The first task is the rear brakes. I noticed as soon as I tried to push it out of it's corner that the rear brakes were binding and only brute force and ignorance got it moving.
Sadly we don't have the luxury of lot's of classic parts suppliers over here and after a fruitless hunt with our local parts guys, I haven't managed to find any rebuild kits.
I can get them through ebay, but can't see any ss pistons there. I'm after rebuild kits, including the pistons, plus the 4 hoses.
I see Steven, that you got the pistons out of MGDB. I did an internet search for them, but haven't had any success. Can you give me their contact.
Advice on a good , reasonably priced supplier who exports with reasonable postage rates would be appreciated (postage rates can vary by a factor of 4x or more on international postage, depending on the supplier and can often be more than the item your buying)
Thanks for any help you can give me.
Mike
 
#88
KiwiMike said:
I see Steven, that you got the pistons out of MGDB. I did an internet search for them, but haven't had any success. Can you give me their contact.
Hi Mike, and welcome to the forum.

The site you want is:

MGBD Parts

Owned by Mark and Angie Gray, who are extremely helpful with any queries you may have.

Best of luck.

P.S. Pictures of your car are always welcomed by us forumites :D :D
 
#89
Thanks Phil for the fast reply.

I see I was suffering from dyslexia and I also noticed as soon as I posted, that MGBD was listed in your suppliers.

I've just tried to upload a couple of photos of the poor old girl, but it shows the file size is too large. As a computer inept, I'm not sure how to lower their size.

If someone can tell me how, I'll give it a go.

Mike
 
#90
KiwiMike said:
Thanks Phil for the fast reply.

I see I was suffering from dyslexia and I also noticed as soon as I posted, that MGBD was listed in your suppliers.

I've just tried to upload a couple of photos of the poor old girl, but it shows the file size is too large. As a computer inept, I'm not sure how to lower their size.

If someone can tell me how, I'll give it a go.

Mike
Hi Mike.

You could try here:

Posting Pictures

I use the Windows 'Paint' program to re-size my pictures before uploading them.
 
#91
Just thought I'd share a few reflections on overhauling rear calipers on a '69 TC - first-time job for me.

1. Original problem symptoms were a weak handbrake and binding brakes. The car was effectively undrivable.
2. Take plenty of photographs and notes. They're better reference-check than trusting to a long memory.
3. The workshop manual is accurate. I could trust it at all times.
4. Rear brakes *look* a daunting array of steampunk engineering...until you start removing them when they become easy to understand. Don't be put off, they are actually quite straightforward.
5. Remove the sideshafts and discs. The extra hassle is more than repaid by the ease of access which results. Then whip off the handbrake linkage assembly.
6. Brake pad retainers - the thick end sits below the little pin. Make a note, it's easy to put them back thin-end down.
7. Take out the old brake pads by removing their retainers and pulling the calipers outwards to get the outer pads off their retaining pins, with them gone the inners are a doddle.
8. Remove the caliper pins and brake pipe connection to the feed line as per the manual instructions.
9. Wiggle both calipers out as a unit connected by their rubber hose over the diff and and down on the left side of the car.
10. The connecting hose is worth replacing with a new item.
11. Make a note/photograph of which pipe goes where in the calipers; the bleed nipple too. Once the caliper is stripped down, they all look the same.
12. The handbrake mechanism is a miracle of slide-rule design and a work of the pipe-smoking machinist's art. Follow the manual to break one down. Do a complete job on one at a time so you have an intact one to refer to so you don't get lost. Assembly, I found was psychologically easier than breaking the gubbins down.
13. Don't whatever you do don't forget or lose sight of the tiny handbrake actuating pin!
14. All the O-rings in the service pack are used to try and keep water and winter salt out of the calipers, there's only a single standard-looking seal for the foot brake piston.
15. One of my seal chambers/cylinders was pristine, the other was gunged up with black crud off the seal. It looked bad but cleaned up perfectly with just a mild rub with some super-fine wet-and-dry. (Washed out with surgical spirit - copiously etc. etc..)
16. Reassembly was surprisingly easy. The only puzzle was getting the handbrake springs round the right way. I found pushing down the brake piston gave lots of room to screw on the knurled wheel and everything that goes in on top with it. The manual is accurate on this.
17. Refit the connection hose (new) and the main fluid supply (new and the one with the spring around it).
18.Use string to ensure the brake actuating rods don't fall out while you wrangle the calipers back into position and refit their mounting pins. (Again, the manual makes this point clear.)

Some additional personals:
1. I used monofilament to attach a silica gel sachet inside each caliper. The "special paper" was missing in one and rubbish in the other. Whether this shady tree bodge serves any long term purpose I have no idea...it just seemed like a cool thing to do.
2. Copperslip grease applied to the caliper pins and fastenings. Assuming the rinky-dink O-rings are designed to keep the elements out, non-drying grease that's kind to them can't go awry.
3. Standard brake assembly grease and oil was used for the caliper internals.
4. The handbrake is extraordinarily sensitive to small adjustments in the cable. Do this last of all and make sure the brake quadrants rest on their pins. Four-five clicks on the handbrake should lock up the brakes HARD, but the back wheels spin freely when the handbrake lever is dropped.
 

Dave3066

Well-Known Member
#93
harveyp6 said:
Keith Coman said:
3. The workshop manual is accurate. I could trust it at all times.
If you include fitting the rear pads as part of the rear caliper overhaul, then the WM is incorrect.
Is it factually incorrect, or is there simply a better way to do the job. Just curious as I've not looked at the WM manual for rear pad replacement. I've always used your method :D

Dave
 

harveyp6

Well-Known Member
#95
To clarify, I've just looked in the 2 WM's, V8 one shows them correctly fitted, 2000/2200 shows them incorrectly fitted in one illustration and correct in another, so caution required. I'm not sure whether having it shown wrong and right makes it better or worse. The place to look is in the fitting sheet that used to come in with the Girling pads, but I doubt there's many of those around. Like you, I never look in the book when doing them, and it only came to light when I set up a set for someone who'd fitted the pads following the procedure in the book and they were the wrong way around, and his protests prompted a look in the book, which absolved the guilty party of all responsibility. (You know who you are..... :LOL: )It was easily sorted, and he could blame the book, so a good result all the way around really.

I suppose it's not unreasonable to expect errors to creep in there, as with the others that have been mentioned here over the years. It may even be that later versions of the book(s) rectified the error.
 

harveyp6

Well-Known Member
#97
The Rovering Member said:
An understandable mistake. :oops:

You know how thin my anorak is.

Ah, so you remember then. I was beginning to think I dreamt it.......

You summer weight anorak does you proud sir, give it time, polar explorer type awaits you.... :LOL:
 

Dave3066

Well-Known Member
#99
harveyp6 said:
To clarify, I've just looked in the 2 WM's, V8 one shows them correctly fitted, 2000/2200 shows them incorrectly fitted in one illustration and correct in another, so caution required. I'm not sure whether having it shown wrong and right makes it better or worse.
Thanks H.

Dave
 
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