In This Quick Job Guide i will show you how to re-new the rear brakes on your MGB or MGBGT. This guide will take you through the basic process for replacing the brake shoes, springs and hand brake links, I will cover the brake cylinders and bleeding them through in a seperate guide.
First its best to start with the car placed up on axle stands and the rear wheels removed, remember you will need to loosen the wheel nuts or spinner with the car on the ground first before lifting the car. With the wheel removed you should be left with a drum, this is then removed by firstly taking out the two securing screws or 4 fixing nuts, to remove the drum, you may find it easier to hit it from behind (NOTE: make sure the hand brake is off and the drum rotates freely first, if it doesnt rotate with the hand brake off turn the adjuster anti clockwise to pull the brake shoes in). You should now be able to see the brake shoes, springs, cylinder adjuster body and the hand brake links.
To remove the brake shoes, first release the two behive springs and their locating cups and tags, these are located in the middle of each shoe, you will need a pair of good pliers for this. With the pliers grip the spring cup end on and push in, with your other hand locate the back of the tag and hold it in place, turn the pliers 90 degrees and the spring and cup should come free, repeate for each shoe. (NOTE: its good practice to make a note of how each spring fits take photos with your camera so you can see how it goes back together easier). Its now time to slacken off the adjuster, this is located at the top of the back plate, its slackened from behind, there should be a threaded bolt with a square end, turn it anti clockwise untill it stops, be aware that these usually become rusted solid so may not work correctly, they are easilly replaced though, which is done by the two nuts on the back.
You should now be able to move each of the shoes over the end of the adjuster, once you do this you will find that it all pretty much comes appart in your hands, you will also need to remove the spring for the hand brake link to get both shoes off. With the shoes and springs removed, if you want to replace the hand brake links this is the time to do it, be aware that they are handed. These remove very easily its a simple case of removing the split pin and pin from the hand brake cable and then pulling the linkage out, to refit it its just the reversal.
Now comes the fun part of rebuilding the system, persoanlly i prefer to use all new springs, but you can use the old ones if you wish. In its simplist form the rebuild is the reversal of the procedure above, it is awkward at times and can be fustraiting as the springs will no doubt come out of the holes in the shoes when you dont want them to but it will all go with a little persaverance. I have found it best to assemble the shoes and main springs off the car to begin with so that im happy with where each spring goes, then as a “complete” unit drop it into more or less the right place, once it is sort of on, i try and get the shoes into the brake cylinder fixings first, followed by the adjuster. You will probably find that at this stage you will have a bit of play in the shoes back and forth this is where the bee hive springs come in. Now these can be a pain in the backside to fit, but they will go, it some times just takes some brute force and some luck. With your pliers grip the spring and locating cup in place, with your other hand use a finger to try and hold the tag in its place, push in with your pliers against the spring and twist 90 degreees untill the tag is located on the cup. It will take a number of attempts to do this, but it must be done, so keep at it. All that should be left then is the spring for the hand brake linkage, this again can be a fiddle to fit but should be do-able with a screw driver and pliers, again some brute strength is needed. You should now have something that looks like the photos below:
All that remains is to fit the drums and hold them in place with the relevant screws or nuts, once the drum is fitted, move the adjuster in a clock wise direction to push the brake shoes onto the drum, so that it can not be turned by hand, then slacken it back so that the drum moves freely or with a little resistance. Once you have refitted the wheels and tightened up the wheel nuts or spinners lower the car and re tighten the wheel fittings and your all done ready to go for a drive.
Generally this whole process should take not much longer than 30 mins for each side, just take your time doing it, and always take photos as your going along as these will help you when it comes to putting it all back together again.