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Parking brake or emergency brake? Fact of the matter is, the brake we often refer to as an emergency brake is primarily meant for holding the stopped car in place and is not particularly well suited to stopping the car when it's rolling down the road. In the owners' manual (not to mention the red instrument panel light that warns you that the brake is set), Volvo refers to it as a "Parking Brake." This is not to say that it isn't darned handy in an emergency, but the small shoes that are fitted inside the rear rotors simply don't provide enough braking power to stop the car effectively from speed, although they might slow you down a lot (I'll leave discussion of bootlegger turns to those with more experience in these matters).
Certainly, the parking brakes can provide a considerable drag, and even lock up the rear wheels, if they are properly adjusted and have enough lining left. The parking brake is completely mechanical and independent of the hydraulic brake system. If you are ever in the unenviable position of experiencing foot brake failure, you will certainly be mighty glad to have a hand brake that works.
Many of the older 240-series cars that I have worked on have had little or no parking brake left. Of the two major faults of 240 parking brakes, probably the most common is that the friction material on the shoes has completely worn away. This is likely to be caused by age and possibly abuse. Even when the warning lamp works, some people seem to be able to drive off with the brake set and this is as hard on the brake shoes as it is on gas mileage. Once the lining is gone, the cables will have no more adjustment left in them and the lever will pull up easily with no effect.
The second most common fault is that various brake parts have seized due to rust from years of disuse. Particularly when the car has an automatic transmission, many people will leave the car without setting the parking brake. This is not an especially good idea, because the pawl that holds the car in park is not infallible. In the case of a standard transmission, leaving the car in gear without setting the parking brake may be adequate on a level surface, but the car can often still roll a little bit if left on a slope and, in rare cases, it can even roll away.
The most important reason to use your brake is because it needs the exercise. Even if you never park on a steep incline, you might like to have the brake at the ready when it's time for your annual safety inspection. Here in Maine, you can't get that all-important sticker without a parking brake that works.
On the 240, the cables for the parking brakes are completely sheathed, an overall improvement from the earlier 140/120 cables that were open to moisture and corrosion. Only when the outer sheathing has been damaged, or in severe case of disuse, does the cable become useless. Each cable runs independently back from the hand brake lever in the passenger compartment to the lever mechanism that operates the brake on each rear wheel. This system is much less prone to the effects of weather than its predecessors.
Each cable is adjusted with a 10mm wrench on the locking nut that threads onto the end of the cable. At minimum, the nuts should have 2mm of threaded cable end showing. The cables can be tightened up to the limit of the threaded part. To do this, first loosen the main adjusting screw at the back of the lever mechanism. Pull out the rear seat ashtray, and use a 17mm socket and extension to reach it. Be very careful not to mess up the wiring for the ashtray light, or the seat belt warning light that runs back there. A short in this wiring can have broader consequences than merely taking out these relatively unimportant interior lights. I worked on an '86 240 that lost its turn signals from a short in these wires.
If you are lucky, you will find that simply adjusting the cables (or the star adjusters, in models so fitted) will give your parking brake a new lease on life. If not, then you are probably in for an adventure in parking brake shoe R&R (no, sorry, not rest and relaxation). While the actuator and cables are different, the inner workings of the emergency brakes are very similar to that of the 140. The shoes fit inside the disc brake rotor using the inside of the rotor as a drum. Note that some models have star wheel type adjusters and some have only spacers for the shoes to fit into at the top. Models with Girling rear brakes, found on 140 and early 240, usually have these adjusters and have no "crash block" fitted to the rear of the caliper with a single bolt.
Some of the tools and supplies you will need are:
To replace the parking brake shoes, place blocks securely in front of the front wheels, jack the rear of the car up and let it down securely on jackstands. I prefer to use the factory jack points for the stands and I use a floor jack under the differential housing to lift the car. This method will make the job easier, since, once the wheels are off, you will have to remove the caliper mounting bolts and hang the caliper safely from a strong wire or a hook so that it will be out of the way. If the jackstands are under the body and you have raised the car enough, the rear end will hang down enough so that you can take the calipers off without removing the crash blocks (aka guard plate) on the rear of the calipers (Ate calipers). If it is time to replace the rear foot brake pads, plan to take care of this before you remove the calipers so you can put everything back together and be done once the parking brake is in order.
Once the caliper is removed and safely hanging so that there is no strain on the brake lines, remove the rotor. This isn't always easy and you may need to tap somewhat insistently around the outside of the drum with a hammer to loosen it up. Examine the rotors and consider whether they need to be turned or replaced while you're here.
Note: I can't recommend enough working on one side at a time and using the other side as a reference for putting everything back in its proper place. No picture in the manual will do the job as well as an example.
This done, remove the rest of the brake parts and clean them off with brake cleaner. This is best done with ventilation, as the brake cleaner itself is strong stuff. Try not to get brake dust into the air, as it can contain asbestos. Examine the brake parts for oil and grease. If the brake shoes are grease-soaked, it is not a good sign. It may mean you have a bad axle seal and this is the time to address that, as well.
When disassembling the brake, be extra careful not to lose the tiny pin that holds the parking brake actuator on the cable end. It's not only small, but it is not held in place by anything, except maybe rust.
If you have brakes with star adjusters, be sure, on reassembly, that they are turned all the way in so that you have as much slack as you can get for refitting the rotors. If you have spacer bars, be certain that the cable adjuster at the back of the brake lever is slacked off all the way, or you may run into difficulty trying to slide the drum over the new, much thicker shoes. I have never retrofitted them myself, but I understand that the star adjusters are available through Volvo and can be installed on models that originally had the spacer bars. The rotors all have the hole for adjusting them, so, if you want this extra measure of adjustability, you might want to consider this.
Replacing the cables, if you need to, is a job best accomplished while you already have the brakes apart, as most of the above steps have to be carried out in order out to replace them. Once you have removed the adjuster lever from the parking brake, the cable is free to be removed (I'll remind you here how easy it is to lose the little pin that holds the cable end to the adjuster at the wheel end). The cables are identical for both sides and are crossed over the differential so that, inside the car, the right cable operates the left brake. Removing them involves removing the bolt that holds the cable housing to the axle. Then, inside the car, lift the rear seat bottom and pull back the carpet to access the holes where the cables enter the passenger compartment. There is a clip under the carpet that has to be released, as well. Be sure the cable adjuster at the back of the hand brake lever is fully slacked off and remove the locking nuts from the cable ends before trying to pull them out from below the car.
While repairing your parking brakes is definitely more involved than replacing disc brake pads, it is by no means a job that can't be approached by a determined shade tree mechanic. Once you have a parking brake that works, the only thing you need to remember to do is to use it when you park the car (the exception to this rule is cars that will be in storage for long periods of time). If you use your parking brake, then it will be there for you if you ever need it as an emergency brake. The security of this knowledge makes the project well worth the effort.
Visit Lee's web site at www.volvogirl.com