Just a Simple Wrench
by Ann & Jake Snyder
Slow and Easy
MGs do not have much extra in the way of controls or instruments, and anything that does not work takes a lot away from the enjoyment of driving. And from the security of stopping and staying stopped. One of the most frequently neglected devices is the parking brake, which also doubles as a not very efficient emergency backup to the real brakes. We learned a long time ago that trusting the gearbox to hold a parked MG is not always reliable. Fortunately, the car dug itself into a depression in the lawn before it ran onto the road, and there were no personal injuries or property damage. But it took a bunch of guys to get the roadster on the road again.
The most common problem is that the lever cannot be moved. The second most common is that the brakes cannot be set hard enough to hold the car on a hill. And that leaves the nasty one, of the brakes not releasing, as a close third. The common elements in these problems are rusted components and misadjustment.
The very first thing to do if the hand brake on your MG is not reliable is to buy and carry a set of plastic wheel chocks. These cost about five dollars, and you will know when you need to use them.
Then repair the parking brake. Start by taking care of the rust. The cable rusts first, and if this is not corrected promptly, the connecting levers in the rear brakes and the handbrake lever itself will follow, given enough time. The cable can be freed up sometimes and will work a little longer. Freeing a rusted cable involves first removing it. Hold the housing in a vise (gently), and heat with a propane torch while pulling and twisting the cable in the direction it is wound. Applications of used motor oil (don’t breathe the smoke) and penetrating oil may be necessary. If the cable does free up in a reasonable amount of time and effort, grease it at both ends and through the fitting with waterproof grease, and pull the cable the full length possible. . The problem with buying a new cable is that there are several different lengths, depending on wire wheels or disk wheels. Needless to say, if the car has disk wheels on a wire wheel rear axle, as we have on one of the GTs, the easy way to get a cable that fits is to buy both of them and pick the one that works best.
The levers in the rear brake assembly also rust. These cause the particularly aggravating situation where a hand brake is set, and the lever in the passenger compartment will release, but one or both of the rear brakes drag. Then the levers that stick out of the brake backing plates must be returned manually, which means getting out of the car and crawling under the back end and getting dirty and probably hitting your head. Rusted levers must be removed and wire-wheeled, wire brushed and whatever else works to get them free. They must be painted, or rust will start immediately. Lube the pivot point with a little grease or anti-sieze, without greasing the linings, of course.
We have had situations where the hand brake lever was rusted where the shaft fits through the mounting (rachet) plate, the consequence of long neglect to the parking brake system. This is extremely difficult to loosen, and removing the hand brake lever from a rusty car is a major effort if the mounting bolts are also rusted, and they will be. Take out the passenger’s seat, and use anything except a cutting torch to get the brake lever out. Drilling and retapping may be required. The hand brake levers and rachet plates are expensive or impossible to get as new parts, and seldom are used brake levers recovered before a car is scrapped, so there are not a lot of extra ones around.
Put everything back together, and start by adjusting the rear brakes to the shop manual specifications. Too loose an adjustment here will undo all the work on the parking brake system. (A trick we learned not to do is to compensate for wear on the lining by pulling the hand brake just a little in normal use. This gave too much travel to the rear wheel cylinder pistons, and leaking brake fluid was the payment for laziness). Use the proper hardware for the attachment to the hand brake lever. Buy everything new, including the brass nut if the old one cannot be cleaned and rethreaded. Adjust the brass nut until the brakes set tightly when the hand brake lever is half-way through its travel. If the rear wheels cannot be locked tightly with the hand brake, check for excessive cable length (fit another one) and for excessive wear on the emergency brake levers in the rear brake assembly. These do wear enough on high-mileage cars to result in no or little contact with the brake shoe when they are fully actuated. These can be repaired by welding and “selective fitting “: grind a little bit off or weld a little more on as required for proper action.
There are a few weird things that can effect the handbrake when the car is in use. One is an improperly fitted exhaust system that deflects the cable, causing the rear brakes to engage under changing suspension loads. This translates into a pull when going over a bump. Another strange event occurs if the rear springs will not support the car and load weight adequately. The rubber axle travel-limiting straps can fold either to the front of the car or to the rear. If they fold to the rear, the hand brake cable will be deflected, with exactly the same consequences as when the exhaust system fouls the cable. The straps can be temporarily bungee-corded to induce folding to the front until the springs can be rebuilt.
Proper and frequent use of the hand brake is essential to keep rust from reforming and in adjustment. Set the handbrake slowly and easily. Remember that the button must be depressed and the handle lifted one more notch up when releasing the brake, so that setting the hand brake as tightly as possible with a violent jerk serves only to stretch the cable and make releasing the brake very difficult. Set the brake at long traffic lights: The more it is used the longer it will last.
 
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