Replacing rear handbrake shoes

[Styria]

Hi all, this is just an oversize whinge (sorry Mark !). Has anyone tried to remove those brake shoes from the rear hub of a 450/6.9 ? Obviously I have, and honestly, I dread the thought of having to carry out this replacement. Removal is only possible by removal of four springs - two that hold the shoes together onto the steady post and threaded and splined adjustment wheel, and the other two that hold the shoes to the backing plate.

Honestly, a worse job you couldn't think of. "Worse" because it is such a poor design, unnecessarily complicated and try and remove the small springs that hold the shoes to the plate - well, in fact, all four are an absolute frustration and much cause for cursing. Perhaps if one had a special tool, the job might be easier, but really, I just can't believe it. No pics, and no description of which is the best way to do the job - I just say it is an unbelievable fiddle. Total frustration. Regards Styria

 

[Oversize]

Aw c'mon Styria I can think of many other jobs you've completed that're far worse! Personally I don't think they're that bad and are very similar to other designs. Large nose pliers and multigrips do the trick for me! Drum brakes have always been pretty rubbish anyway and fortunately they're just a park brake, not the service brakes....

 

[Tony66_au]

If the springs are of the push and twist to release there is a common tool like a screwdriver shaft with a notch cut in the end, and as for the tension springs that go between the shoes any decent long handled pick hook will do the job.

I did my 124 230 TE handbrake shoes with minimum fuss and these service tools although I did replace all 4 springs as well.

A hoist would make the job far easier as well.

Perhaps some pictures of the 6.9 assembly would help?

Tony

 

[Tony66_au]

I just re read your post Styria and thats identical to the TE shoes, There were access holes in the assembly on the TE and I did brake the twist to remove placement springs removing them so replacements are a must.

 

[Oversize]

I don't think I've ever broken a spring, but it's been quite a while since I've had a go and they're obviously much older now (so am I)!

 

[Helmet]

You forgot to add that making the handbrake actually hold the car on a hill is a feat in itself

 

[Styria]

You forgot to add that making the handbrake actually hold the car on a hill is a feat in itself

Hi Helmet, if you are addressing me, I need to tell you that I haven't gotten that far yet. The replacement/moving of the shoes is only ever part of an operation. Talking however, of the handbrake holding, is another little chapter altogether. I find that a number of adjustments are required over short periods to get the linings bedded in. Once that's done, the effectiveness is not half bad - if you know what I mean.

Well Mark, I get the drift that I have done more difficult things, such as 6.9 valve grinds etc. I just find that those little locating springs that you need to push and turn can really (with a slotted screwdriver) drive you to distraction as in "push and turn and push, push push and twist and turn, and turn and twist and push and how long is a string after 5 minutes, ten minutes, half an hour, you finish pushing, turning, twisting" - do you now understand where I am coming from ? In the end, I got fed up and snipped the little bugger with a pair of sidecutters. The trouble is that one cannot see the hook that's on the inside of the backing plate and totally hidden from view by the hub assembly. On the 108s and 109s, at least one can see the hooks and even push them towards the opening slot with a long screwdriver. No, I am not impressed. Regards Styria

 

[Styria]

I don't think anyone has ever put in a better post than our Bill (WGB) covering this very subject. The attached link will hopefully show you why.

http://www.topklasse.org/forums/showthread.php?t=2615

Regards Styria - thanks a million, Bill. I am sure posting all pics must have taken longer than the job itself. I tend to think that the slotted tool as illustrated would probably ease the job considerably when compared with using a slotted screwdriver.

N.B. I would just like to add a little footnote in relation to Bill's excellent post - hope you don't mind, Bill. It took me a bit of time to work out that Bill started with an illustration of the right rear brake shoes arrangement. Subsequent pictures, however, illustrate the left hand side. It took a little while to work out why the springs were located on the inside, rather than the outside which, of course, they're not. I also found that it was easier to fit the large spring to the shoes first and locate them on the steady post, rather than the other way around as suggested in the workshop manual.

 

[abl567]

You forgot to add that making the handbrake actually hold the car on a hill is a feat in itself

They have handbrakes?

 

[Styria]

They have handbrakes?

I know they're a bit hard to find under the dash of the 109s. We could easily take this subject further. Hands up who has replaced the handbrake cable from the lever under the dash to the first junction - and furthermore, fodder for another subject - the price of that cable, plus the price of the solid, black encased cable that leads to the backing plate. Any takers ? Regards Styria

N.B. This should be funny. I am getting up tomorrow about three-ish to check for responses.

 

[WGB]

I just re-read my hand brake post and it reminded me how important it is to actually do it in the order mentioned in the post.

That handbrake mechanism is a very tight fit behind the hub flange.

If you don't do it by the book it makes for a lot of lost time and stomach lining.

About four years ago I replaced the left hand rear cable on my 450. The left hand cabe runs over the exhaust which tends to open up the plastic covering and allow water into the cable which causes rust and then it seizes .

Many second hand options suffer from the same problem with the left hand cable.

There are two versions of the cable as mentioned in the posting and a new second type cable with stirrup on the cable was $160 from Diesel Motors at the time.

Bill

 

[Styria]

Bill, of course, is spot on with his assessment of the left rear cable ceasing as a result of water getting in and rust forming. I finished up having to disconnect the cables right where you have a 'zig-zag' bracket in the centre tunnel area, but it was necessary to disconnect the heat shield to gain access to the fitting. Removing the cable proved stubborn because of the seizing and also the cable had to be separated from the fulcrum fitting that activates the handbrake shoes.

I was lucky - with some patience, I managed to free up the cable by squirting INOX into the opening. Eventually it started to work freely. A new replacement, I believe, sells for about $A250.00, but I stand to be corrected. Anyway, all's well that ends well - SO FAR. All components still have to be refitted. Regards Styria

 

[Styria]

Speaking of handbrake efficiency, i.e. in holding a car to a stand still with engine idling and in gear. Very few cars (116s) that I have come across will give you that sort of efficiency. No matter how well one adjusts the shoes, and how often, there is no way that the handbrake will work properly if the cable is seized (or partially) up because the cable will simply not activity the shoes properly against the internal drum of the rear disc.

Come to think of it, Goldie (my 450SE) has a badly seized left hand cable and no amount of adjustment is going to provide an efficient operation of the handbrake. Another possibly potential, but I think real, problem would arise if one was to endeavour replacement of a seized cable. The shoes, and expander, are hard enough to remove if the system is good, or near enough, but if one can't separate the cable from the expander, what is the solution ? Maybe someone can come up with a brilliant idea. Regards Styria

 

[Tony66_au]

I got knocked back on a roadworthy because the anally retentive Tester said the hand brake was inoperable.

What he should have said was that it wouldn't hold on a forward downhill slope and although it held fine facing uphill, downhill was a definite wheels to the curb job.

I found the following to be true in the way of issues and fixes though, Firstly it was just after asbestos linings were banned and the coconut/peanut husk combinations had kicked in.

Secondly the setup was using existing drum system inside the disk and although the disk had been machined the E brake drum had not.

So to compensate I tore the disk off and had the drum roughly sanded out with a drum sander creating some fairly brutal cross hatching, Crude but effective and the scoring was done in such a manner as to work well in both directions of rotation.

Thirdly I also roughed up the new shoes and then adjusted them so they were well clear of the drum when released so there was no friction causing glazing of the shoes and adjusted the cables up to compensate for the backed off shoes.

The car now held firm both ways and the tester grudgingly passed the car.

The issues were created by some bad habits such as applying the handbrake before coming to a dead stop as well as the new shoes sweating some oil and glazing due to the change in compound, all overcome by a bit of outside the box thinking.