No Brakes!!

[59Elva]

I finally got motor vehicle to give me a registration. I put plates on the truck and took it out for a test drive around the block. I have a firm pedal but pressing it does little to slow forward motion. While the parking brake will hold the truck from rolling it also does little once underway. All the drums and linings were cleaned and lightly sanded. All adjusted.
Very disappointing. I had hoped to take it to a local car show this evening. Back on the jacks tomorrow I guess.

[Bill_qaz]

Are your wheel cylinder seized? also the rears need to slide on the backplates as single piston.

[59Elva]

Hard to diagnose working alone without assistance. The wife has a bad hip, don’t think she could get behind the wheel. Maybe a push stick.

[svenedin]

I know what you mean. It is hard to do certain jobs without any assistance. If your car stood unused for a significant time or had a history of poor maintenance it is likely there is corrosion in the braking system. Water accumulates in the brake fluid and this corrodes the bores of the wheel cylinders and sometimes the master cylinder. Seals deteriorate, cylinders leak. Perhaps you can jam the brake pedal down with something and go around and see if there is any braking force at the wheels with all the wheels off the ground. You can also see if cylinders are jammed by taking the drum off and applying the brake pedal carefully. Trouble is, you can pop the piston out of the cylinder if not careful. At the front where there are 2x cylinders per drum you would have to take the drum off to determine whether both cylinders are working. You can restrain the piston loosely with wire allowing it to move but not pop out. If a cylinder is stuck badly it may be so corroded internally that it must be replaced. You could try freeing off stuck cylinders but they may then leak due to bore damage. To prevent this happening in future either change the brake fluid every 2 years or change over to Silicone brake fluid. Many owners use Silicone brake fluid and have permanently said goodbye to seized cylinders (myself included).

Stephen

[moggiethouable]

I would agree with the seized brake cylinder comments.
Nice easy job to change them all and not too expensive.

[simmitc]

Not a perfect test, but does give an indication of where to look.

Jack up one front wheel and support appropriately. Spin the wheel fast by hand. It should carry on spinning freely. Press brake pedal. Does wheel stop sharply? Yes = at least one of those cylinders is OK, no = both cylinders seized. Repeat for other side.

Rear brakes, raise both wheels and get them spinning by using the engine in gear. If either wheel does not stop, then that cylinder is seized.

[jaekl]

I've been checking for seize cylinders by myself for over fifty years. All that is needed is a long stick like a push broom handle. Take the drum off, open the door for the rears and through the window for the fronts, and push the brake pedal. Good working cylinders only require a light push. For the fronts watch for one of the pistons to move and let it return. Now hold a screwdriver between the shoe and the backing plate to restrict the movement of the first to move piston so that the fluid can be directed to the other cylinder. The passenger front is the trickiest and I typically place the stick on the edge of the pedal, otherwise it will slip. No, I do not have long arms and am below average height. Disc brakes are less prone to seize but spinning the wheel and pushing the stick will confirm action. Also confirm the front brakes are on the correct side so there are two leading shoes.

[59Elva]

Thanks guys,
When the truck rolled off the trailer the driver said “no brakes “. The pedal went to the floor. Repeated pumping would get maybe a 1/2” off the floor. Copious bleeding and some push rod adjustment brought back a firm pedal. I saw no leaks anywhere. Externally the hoses look fresh.
If I reach thru the drum hole and back the adjusters all the way off should I see a noticeable drop in the pedal if the cylinders aren’t seized? I am puzzled that the hand brake is so ineffective while rolling since it does hold pretty well when stopped.
Remember that with ESM and other UK suppliers boycotting the US replacement part availability has deteriorated. I wish I could just pop down to the local store and replace everything. What is the situation with reproduction parts? I’ve heard that there are low quality parts from China and India out there.

[RustAndMagic]

A lot of reproduction parts are (Chinese) rubbish these days, goes for all old cars.

The sad thing is that you have 2 alternatives, buy cheap Chinese rubbish that does not last long, or in some cases you can buy good quality parts manufactured in other places or even original parts, but they cost silly amounts of money, there is nothing in between.

I would not read too much into the parking brake, not sure what you mean but even good working parking brakes are not of much use to slow down the car.

[59Elva]

I have replacement front cylinders on order. Hopefully by Friday. Both left front cylinders are solidly frozen. Im about to remove them. None of the manuals I have show the hose or crossover pipe connections. I suspect mine are upside down. Wouldn’t it make sense for the bleeder to be uppermost? This is what I have:

[svenedin]

Yes they're upside down. The cylinders are handed so they are the wrong handedness. You have two right hand cylinders on the wrong side. The crossover pipe should fit into the recessed area of the backplate. I'll look for a photo.

Stephen


Like this. Note the flexible hose is not attached at the other end in this photo. Extra points for spotting this is actually a Wolseley 1500 (Morris Major) set-up but the same principle applies.

IMG_1628.jpeg (1.72 MiB) Viewed 4374 times

[59Elva]

Thanks Stephen,
I think the cylinders are the correct hand for the left side. The setup would result in leading shoes wouldn’t it?
I think the front return spring should be in the upper hole in the top shoe?

[svenedin]

Thanks Stephen,
I think the cylinders are the correct hand for the left side. The setup would result in leading shoes wouldn’t it?
I think the front return spring should be in the upper hole in the top shoe?

Yes this looks correct to me. I have compared it to one of my photos of the same side. However, the handedness of the cylinders is which way up the piston is AND whether the fixing holes to backplate are in the right place......

Stephen

[59Elva]

My replacement front wheel cylinders arrived yesterday evening from Rock Auto. They are Beck Arnley brand and the box says “made in Italy”. We shall see. Out of the six cylinders on the truck only the left rear and one of the right fronts wasn’t frozen.
Has anyone successfully unstuck/salvaged a cylinder? I’ve heard of fitting a zerk nipple and pumping out the piston with a grease gun?
The post office says that my MGB ignition switch (probably made in China) is also to be delivered today. I could have both vehicles back on the road by Monday.

[mowogg]

Saved quite a lot in my youth. As described use a grease gun to disassemble and then clean and inspect the cylinder. If the surface is ok it can be reused. You often find it's sized up with grot

I always put some red brake grease on the slave in reassembly

[jaekl]

Seize pistons are a way of life until you switch to silicone brake fluid. You can't hone the rear cylinders due to the slot for the handbrake lever. However, being aluminum they clean up easily with steel wool.

[ManyMinors]

They are only "a way of life" if you don't use your car often enough. If you drive your car regularly and maintain it regularly the cylinders are long lasting even with standard fluid.
New wheel cylinders are cheap enough anyway when they ARE needed.

[jaekl]

Even when used regularly, I would check the cylinders at every 1000 mile greasing it was common to find one seize cylinder. Although, I am guilty of not changing the fluid. Less frequently seized cylinder were also found on more modern Detroit vehicles. One was less than a year old.

[59Elva]

I installed three new front wheel cylinders and spent hours and almost half a quart (US) of fluid bleeding the system. My Miteyvac hand pump wasn’t up to the job so I tried a motorised pump I bought a decade ago. It seemed to work at the rear. At the front it was just sucking wind. I suspected air was leaking around the bleeder threads so I wrapped them with some teflon tape. This helped some but still a lot of bubbles. I switched to pumping the pedal into a jar. I had a one way check valve and silicone tubing salvaged from a Kurig coffee maker. I have a firm pedal but only about an inch from the floor. Took a low speed drive around the neighborhood. Initial push doesn’t do much but a second stab will dip the nose and dump the tools on the passenger seat but not lock any tires.
Any thoughts? Do I need a bleeder assistant? Maybe new linings? Or am I looking at a master cylinder transplant? At one point when the cylinders were frozen I did have a high firm pedal, just no stopping power.

[mowogg]

Bleeding brakes can be an issue i i have spent a few happy hours trying to bleed mine over the years. Before you go much further, are you happy the flexis are in good condition? These can cause some issues, and if you have doubts I would replace these.


I normally find its much easier to bleed brakes with 2 people -you are not relying on non return valves