Some repairs and services to our LBCs are glamorous. Some make them run a lot better and some make them look really good or stop much better, but there are other things that need to be attended to from time to time that are just background noise. Noise that left ignored will cause you grief.
One of these tasks is keeping the parking brake in good order so that it not only works, but also doesn’t interfere with the rest of the rear braking system.
Most of what I will write here is set out in the usual MGB maintenance books, but somehow their dry directions can put off and confuse an average weekend MG guy, so what I have tried to do here is to make tings a little more “everyday understandable” and ultimately a little more enjoyable.
Don’t get me wrong though. This is one of those messy and time consuming jobs. You are going to need access to a solvent bath and a work bench. A #2 Phillips screw driver, 3/8”, 7/16”, ˝” and 9/16” wrenches should be at hand along with a pair of pliers and some shop towels. A squirt can of oil, some penetrate such as PB Blaster, a wire brush and some compressed air if you can manage it will round out the tool department.
The entire system lives under the car where it catches all of the dirt, salt, road goo and road kill that can be caught. The cable soaks up moisture and grit, it is neglected and rarely lubricated. The lever system that transfers the cable movement out to the individual wheels binds up from rust and road nasties. The mechanism at the bottom of the lever inside the cabin gets dirty and binds up.
Most of these things don’t really wear out. Instead they just get so dirty and tight that their parts won’t move.
What I will describe here is a normal cable system service. It does not address anything inside the drums, like the shoes and their adjustment, or the levers and weather boots that transfer the cable’s efforts directly to the shoes. That stuff is best left for another post.
I use to rehabilitate the cables themselves and it certainly still is an option if you want to spent the time, but as inexpensive as they are these days it doesn’t really make too much sense to me to spend an hour or more cleaning an old one up after it has been sitting in a vat of solvent for a day or so.
Cleaning one up if you must, is not rocket science. The idea is to get it as clean as possible and then get it as lubricated and freely working as you can. Soaking for a day or so in your parts vat is a good beginning. Follow that by drying with a cloth and using compressed air from every possible direction to blow out the gunk and grit. Repeating this several times usually gets the cable to moving in the sheath, and once you are happy with the free movement, you can soak the whole thing in oil for at least a few hours, wipe it dry and then pump grease through the nipple until it flows out both ends of the casing.
On the other hand you can open the box from your parts house and cut out all of that stuff. The only thing that you need to do with a new cable is to pump it full of grease before trying to install it. There is already some grease in the thing, but filling it at this point and knowing positively that all is well is cheap insurance.
The rest of the effort is basically house keeping.
Before you get your hands really dirty, remove the passenger seat.
Then get under the car and remove the clevis pins connecting the cables to the levers at each rear drum. More easily done obviously with the wheels off.
Next, go to the pivot assembly bolted to the differential housing. Two ˝” cap screws hold it on.
Then disconnect the two guides. One is attached to the bottom of the right battery support and the other is attached to the axle.
Then go forward to the front of the cable and remove the long nut that does the adjusting.
Now for a little tedious stuff.
Go back up into the cabin and “almost” remove the small nut that you will find at he extreme back lower corner of the drive shaft tunnel. It is very small, 5/16” or 3/8” as I recall, and might be covered in paint or dirt. For sanity’s sake do not completely remove it. If you do you are going to have a devil of a time getting the clip that is on the other side of the wall to stay in place while you put the nut back on. Doing that is possible by one man, but it isn’t pleasant and in the best of circumstances should be done with one fellow down under the car holding the clip while the other attaches the nut to the stud.
While you are there, remove the ˝” nut just to the rear of the hand lever. It secures the cable stop-block inside the tunnel. When the nut comes free just push the stud through the hole.
Next, carefully pull the cable house backward, freeing it from the clip and then completely out from under the car.
Now, go back into the cabin and remove the three #2 Phillips screws holding the lever assembly to the tunnel and wriggle it out.
The next few steps mostly involve cleaning and lubrication, but if your gray cells are getting little sparse you might want to take a digital photo or two so that you will have a clear reference to just how things are assembled and positioned before you take them apart.
Lay the old and new cables out on your bench side by side first.
Then disassemble the central lever assembly. There is one 1/2” nut on one end of the shaft and a 9/16” nut on the other. The two halves of the arm are held together with a bolt and nut. Take that apart. And allow the fat clevis for the cable to come adrift. You may have to use some penetrate, like PB Blaster to get the rest of the things to part ways, but do get them separated. There will be two flat washers and a spring washer behind the inner arm. Don’t lose them. Finally, unscrew the central pivot shaft from the bracket.
With everything apart, use solvents to get the topsoil off and then use a wire brush to fully clean and polish all of the surfaces of every part.
When everything is super clean reassemble the thing onto the new cable assembly. You do remember exactly how it goes together don’t you. ;-)
Next, clean and polish the two guides and put them on the cable in the correct orientation.
Now go to the long spring and stop washer and the already removed nut from the front of the cable. Clean them up and set them aside.
Finally take the hand lever to your vat and wash it down until it is completely free of grit, dirt, old grease, hairpins and spare change.
Now sit there with a squirt can of oil and shoot everything before walking away to let it drain. After a few minutes come back and wipe off the excess oil so that you can handle things without getting your shirt too messed up.
Assembly is sort of in reverse order, except the I find that attaching the pivot assembly to the differential house first helps to keep things from falling and flopping around too much. Although the rest of it is pretty much a no-brainer, you might want to leave most of the fasteners a little loose until all is basically installed and aligned. Having things wriggle a little helps in some cases.
When you do get to the point of having the cable guides in place look back up into the rear edge of the tunnel and make sure that the small retainer clip is correctly positioned and is holding the cable house snugly to the tunnel wall. You don’t want the cable popping out and rubbing against the drive shaft later on.
After everything is secure go to the rear brakes themselves and adjust them properly.
After all of this you can go to the cabin again and see how the lever moves and how it might have to be adjusted. If it comes up more than a half dozen clicks, perhaps 40 degrees or so, get back under the car and run the big nut on the end of the cable a few turns toward the rear.
Hop out from under the car and check the lever movement again. Repeat the above until you get just the right adjustment.
After all is in place get back under the car with your oil squirt can and soak down every moving part. I personally prefer to use oil instead of grease as it doesn’t have the propensity to attract and retain dirt and grit like grease does, and regular attention with the oil can at every oil and chassis grease service interval will be sufficient to keep all well for many years to come.
Re-installation of the passenger seat is optional, according to the appearance of your potential companion and his/her outlook toward elderly British machines.
One of these tasks is keeping the parking brake in good order so that it not only works, but also doesn’t interfere with the rest of the rear braking system.
Most of what I will write here is set out in the usual MGB maintenance books, but somehow their dry directions can put off and confuse an average weekend MG guy, so what I have tried to do here is to make tings a little more “everyday understandable” and ultimately a little more enjoyable.
Don’t get me wrong though. This is one of those messy and time consuming jobs. You are going to need access to a solvent bath and a work bench. A #2 Phillips screw driver, 3/8”, 7/16”, ˝” and 9/16” wrenches should be at hand along with a pair of pliers and some shop towels. A squirt can of oil, some penetrate such as PB Blaster, a wire brush and some compressed air if you can manage it will round out the tool department.
The entire system lives under the car where it catches all of the dirt, salt, road goo and road kill that can be caught. The cable soaks up moisture and grit, it is neglected and rarely lubricated. The lever system that transfers the cable movement out to the individual wheels binds up from rust and road nasties. The mechanism at the bottom of the lever inside the cabin gets dirty and binds up.
Most of these things don’t really wear out. Instead they just get so dirty and tight that their parts won’t move.
What I will describe here is a normal cable system service. It does not address anything inside the drums, like the shoes and their adjustment, or the levers and weather boots that transfer the cable’s efforts directly to the shoes. That stuff is best left for another post.
I use to rehabilitate the cables themselves and it certainly still is an option if you want to spent the time, but as inexpensive as they are these days it doesn’t really make too much sense to me to spend an hour or more cleaning an old one up after it has been sitting in a vat of solvent for a day or so.
Cleaning one up if you must, is not rocket science. The idea is to get it as clean as possible and then get it as lubricated and freely working as you can. Soaking for a day or so in your parts vat is a good beginning. Follow that by drying with a cloth and using compressed air from every possible direction to blow out the gunk and grit. Repeating this several times usually gets the cable to moving in the sheath, and once you are happy with the free movement, you can soak the whole thing in oil for at least a few hours, wipe it dry and then pump grease through the nipple until it flows out both ends of the casing.
On the other hand you can open the box from your parts house and cut out all of that stuff. The only thing that you need to do with a new cable is to pump it full of grease before trying to install it. There is already some grease in the thing, but filling it at this point and knowing positively that all is well is cheap insurance.
The rest of the effort is basically house keeping.
Before you get your hands really dirty, remove the passenger seat.
Then get under the car and remove the clevis pins connecting the cables to the levers at each rear drum. More easily done obviously with the wheels off.
Next, go to the pivot assembly bolted to the differential housing. Two ˝” cap screws hold it on.
Then disconnect the two guides. One is attached to the bottom of the right battery support and the other is attached to the axle.
Then go forward to the front of the cable and remove the long nut that does the adjusting.
Now for a little tedious stuff.
Go back up into the cabin and “almost” remove the small nut that you will find at he extreme back lower corner of the drive shaft tunnel. It is very small, 5/16” or 3/8” as I recall, and might be covered in paint or dirt. For sanity’s sake do not completely remove it. If you do you are going to have a devil of a time getting the clip that is on the other side of the wall to stay in place while you put the nut back on. Doing that is possible by one man, but it isn’t pleasant and in the best of circumstances should be done with one fellow down under the car holding the clip while the other attaches the nut to the stud.
While you are there, remove the ˝” nut just to the rear of the hand lever. It secures the cable stop-block inside the tunnel. When the nut comes free just push the stud through the hole.
Next, carefully pull the cable house backward, freeing it from the clip and then completely out from under the car.
Now, go back into the cabin and remove the three #2 Phillips screws holding the lever assembly to the tunnel and wriggle it out.
The next few steps mostly involve cleaning and lubrication, but if your gray cells are getting little sparse you might want to take a digital photo or two so that you will have a clear reference to just how things are assembled and positioned before you take them apart.
Lay the old and new cables out on your bench side by side first.
Then disassemble the central lever assembly. There is one 1/2” nut on one end of the shaft and a 9/16” nut on the other. The two halves of the arm are held together with a bolt and nut. Take that apart. And allow the fat clevis for the cable to come adrift. You may have to use some penetrate, like PB Blaster to get the rest of the things to part ways, but do get them separated. There will be two flat washers and a spring washer behind the inner arm. Don’t lose them. Finally, unscrew the central pivot shaft from the bracket.
With everything apart, use solvents to get the topsoil off and then use a wire brush to fully clean and polish all of the surfaces of every part.
When everything is super clean reassemble the thing onto the new cable assembly. You do remember exactly how it goes together don’t you. ;-)
Next, clean and polish the two guides and put them on the cable in the correct orientation.
Now go to the long spring and stop washer and the already removed nut from the front of the cable. Clean them up and set them aside.
Finally take the hand lever to your vat and wash it down until it is completely free of grit, dirt, old grease, hairpins and spare change.
Now sit there with a squirt can of oil and shoot everything before walking away to let it drain. After a few minutes come back and wipe off the excess oil so that you can handle things without getting your shirt too messed up.
Assembly is sort of in reverse order, except the I find that attaching the pivot assembly to the differential house first helps to keep things from falling and flopping around too much. Although the rest of it is pretty much a no-brainer, you might want to leave most of the fasteners a little loose until all is basically installed and aligned. Having things wriggle a little helps in some cases.
When you do get to the point of having the cable guides in place look back up into the rear edge of the tunnel and make sure that the small retainer clip is correctly positioned and is holding the cable house snugly to the tunnel wall. You don’t want the cable popping out and rubbing against the drive shaft later on.
After everything is secure go to the rear brakes themselves and adjust them properly.
After all of this you can go to the cabin again and see how the lever moves and how it might have to be adjusted. If it comes up more than a half dozen clicks, perhaps 40 degrees or so, get back under the car and run the big nut on the end of the cable a few turns toward the rear.
Hop out from under the car and check the lever movement again. Repeat the above until you get just the right adjustment.
After all is in place get back under the car with your oil squirt can and soak down every moving part. I personally prefer to use oil instead of grease as it doesn’t have the propensity to attract and retain dirt and grit like grease does, and regular attention with the oil can at every oil and chassis grease service interval will be sufficient to keep all well for many years to come.
Re-installation of the passenger seat is optional, according to the appearance of your potential companion and his/her outlook toward elderly British machines.
Parking Brake Cable - MGB
