Touchy front brakes

[Guest]

Car had been sitting for 5 years. I replaced the brake line from the front to rear of the car and bled the brakes.

The car is a 1960 with ac and power brakes, drum brakes all around.

When I first start the car and move it out of the garage the lightest touch of the brakes stop the car very hard. Is this normal or should I do some adjusting. I have yet to bring the car on the road and try it out.

[simplyconnected]

Drum brakes are by far the most finnicky. Since the front brakes do 85% of the stopping, front drum brakes are THE worst.

When cold, they may pull to one side but after warming up they may pull to the other side. They can absorb water and become 'touchy' from slight bloating or operate in other strange ways. After sitting for long periods of time, a thin layer of rust may form in your drums. Usually, the shoes 'normalize' after being worked.

So, on a cold or brisk morning, the engine is cold, the automatic trans oil is cold, brakes are cold, etc. After the choke opens, the thermostat opens (warming trans fluid in the radiator) and the brakes have cycled a mile or two, your car should drive just fine. Until that happens, do not judge any of the components. Come to think of it, when I first get up from bed I'm kinda creaky and I have to get used to the first few steps. I don't negotiate the steps going down to the kitchen like I do later in the day. - Dave

[simplyconnected]

What ever happened with this, Dan?

[Guest]

I have not looked into it further. I might do a disc brake conversion on the front

[BikeGuy]

My daughter's is the same model ('60, power brakes, etc.). It brakes better after a few miles (as you stated) but still has a bad, bad tendency. Apply the brakes and the front left brake grabs, that corner of the car dips, and the car begins to swerve left. Then thing "right themselves" and the brakes are even and the car steers straight ahead. However, this is unacceptable. Where should I start (after new shocks)?

[jopizz]

Before any of us can try and diagnose what the trouble is we need to know the condition of the components themselves. Have the wheel cylinders been replaced, have the linings and drums been checked. How old is the master cylinder. Have the brakes been bled. Have the rubber hoses been replaced. When all the components are new and adjusted correctly drum brakes will give you satisfactory performance. However, age in any of the parts will cause poor performance. Since the left front wheel is closest to the master cylinder air in the system will often cause that wheel to lock up.

John

[simplyconnected]

John is right, it's hard to say without knowing the background or seeing these parts. But regardless, I suggest you retrofit with power disk brakes. I always suggest this because it makes a HUGE difference in stopping and pads don't have the same bad habits that shoes have. (Once I tried power disk brakes, I will never go back to drums.)

If you must stay with drums, it's a guessing game for me; what do the mating surfaces look like, are the shoes soaked with brake fluid (oil or grease), are the primary and secondary shoes installed correctly, does the M/C or booster leak..? - Dave

[BikeGuy]

Looks like the last owner replaced all brake shoes and turned the drums. Wheel cyls. were not rebuilt and everything else looks original (or dated, anyway). I'll start with bleeding the lines with fresh fluid and see where that gets us. I will look into rebuilding wheel cyls. next and let you know.

Thanks!

[Dakota Boy]

Be sure you have the brake shoes installed correctly. If you have the two shoes reversed, it can lock up the wheel pretty tight. Luckily, I discovered this when my car was still up on jackstands. This may not be the answer to your problem, but it is just something to be aware of...

[Joe Johnston]

I seem to remember some of the pictures in the shop manuals were incorrect. I don't recall what years though. In general isn't the larger shoe the trailing shoe? Bike Guy (and all of us) need the correct info. Anyone know for sure?

[jopizz]

The longer shoe goes toward the back of the car. There were shop manuals printed that had it backwards.

John

[jopizz]

I will look into rebuilding wheel cyls. next and let you know.

Thanks!

With the price of new front wheel cylinders being around $12 from Rockauto I wouldn't recommend rebuilding yours. If they're the originals they're probably scored past the point of being rehoned.

John

[Joe Johnston]

The longer shoe goes toward the back of the car. There were shop manuals printed that had it backwards.

Thanks for confirmation! Hopefully that will keep some from making mistakes thinking they did it correctly by the book.

Anyone know specifically what years are incorrect in the Shop Manual?

[simplyconnected]

Yes, the longer shoe does go toward the rear of the car BUT sometimes both shoes are the same length.

When they are the same length, the manufacturer (or rebuilder) stamps the side of the lining with "PRI" or "SEC". Again, if the same length, the shoe colors will be different because they are not the same hardness. One is usually grayer and the other is darker.

Changing brakes is not rocket science but the installer must know what's really going on. Subtle nuances are particularly important. If this is your first time changing shoes, get ahold of an experienced old timer and let him watch you.

Do your brakes one-at-a-time so the other side can be referenced. Take LOTS of before and after pictures. If you don't use them for reference, someone else might benefit from them. - Dave

EDIT: Follow your Shop Manual. In Section 10 of the 1960 SM, it clearly shows the PRImary shoe is the front shoe and it is shorter.

[BikeGuy]

UPDATE and question. Recall our car's brakes grabbed on the front left, then settled down.

After reading the car manual, I bled all the brakes and found no air bubbles, fluid is clean and fresh (last owner must have done some work, brake shoes were like new and rubber brake hose on front right too). After replacing all 4 shocks and adjusting front brakes, car now grabs slightly on front right, then front left, then settles down! Shocks have added a lot of add'l control, though.

Next steps. I am about to order new brake hoses, wheel cylinders, shoes and brake hubs. Already replaced the bearings and will reuse those. QUESTION - Will I be able to remove the brake hoses and bolt up the new ones using the same flare in the steel brake lines?