Thread: Do manual brakes always feel like this?

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I took out my roadster yesterday for a spin around the block, and have pretty much determined that I hate how the brakes function. I figured I'd ask some opinions on if they are "normal" or not, as I am generally accustomed to modern power assisted brakes and realize there is a difference between those and manual brakes on a hotrod. The car has GM discs up front, and the big drums out back that were part of the donor 9" ford rear. The master cylinder is mounted under the floor, and has residual valves in place, etc. The first think I notice is that there seems to be alot of pedal travel between where the pedal is at rest and where it actually starts clamping hard on the brakes. It also seems like you gotta stomp them pretty darn hard to get the car slowed down, even at a relatively slow speed, such as coming to a stop sign on a residentail street. It DOES stop, and if you really push the pedal down it will clamp hard, it jsut seems like theres alot of freeplay in the pedal, and excessive pedal effort is needed. They brakes don't "pump up" when you step on the pedal repeatedly, so i don't "think" theres air in the lines or anything, it almost seems like the mechanical action of the pedal arm just needs alot of travel before moving the piston of the master cylinder. That's why I'm asking if this "normal" for this type of brake setup, and if it is how other people's cars are... or if i should start looking into what may be "wrong" with mine. If this is just how manual brakes with an under the floor pedal assembly works, I'll keep driving it and getting used to it, if its not I'll start tearing into stuff. I should also not this car only has about 10 miles on it, and is the first rod I've ever had, so everything about it needs some "getting used to".

What you describe isn't normal. It sounds dangerous.

This can sometimes be a little tough because your frame of reference may be different...........how "lot of travel" is "lot of travel". Manual brakes will take more travel than power, and will take more application force from your leg because there's no assist from the booster (I think you already get that).

Could be that you've got a power brake master cylinder rather than a manual one, that could explain the longer travel you're experiencing. Also the bore size could be too large which reduces the amount of pressure to the calipers.

Can you find out from the builder if he used a "system" from a brake system supplier, and who that would be?

Assuming you have the correct parts installed as Bob has suggested -

Is the master cylinder full of fluid?
Any fluid leakage around the master cylinder?

I would attempt to bleed brakes first.

I had all kinds of similar pb with my brakes set-up, although i do not have disks, I have old drums all around. Today my hiboy brakes nicely but it took some work and it will never brake like a power brake. Sean's Plymouth has power brake and I almost went through the windshiled when I drove it last week

So don't even THINK about comparing the two.

Having said that this is what i did to fix my brake problems:

1- I had a leaky Master Cylinder and replaced it.
2- I then had air in my lines and had to bleed them 3 times.
3- It still did not brake well. My old shop was giving me the run around so I found a new shop and had the new shop check and adjust the drum brakes for me. Before they adjusted them, I had a LOT of travel on the pedal (I mean it braked when the pedal was 1 inch from the floor) and it did not brake well at all and it took a LOT of leg pressure. A simple 30 min adjustment later (free of charge thanks to Troy of Hollywood Hotrods), my brakes were tight, with very little travel and reacted with consistency. My roadster now stopped 300% better.

For many months, as many here know, I was debating on adding a power booster to my roadster. I have now given up on this idea because i longer deem it necessary. By now I am used to the manual brakes AND I also have improved my manual brakes to the point that they do their job OK. This was very obvious when I locked all four of my wheels in 0.1 seconds to avoid the frontal crash with the SUV last month (see my previous post). They now WORK.

So if I were you I would look into adjusting brakes after you check for possible leaks / air and give myself a few thousand miles driving to get used to the Hiboy's brake system. Hope this helps

A small bore master cylinder such as used with manual brakes will have to travel farther to engage the wheel cylinders. It's a matter of volume. It takes a certain amount of volume to begin moving the pads on the front and shoes on the back. A power brake system uses a larger master with more volume moved at the same pedal travel, but the pedal will be harder if used without a booster. Bigger bore, more volume moved, less pedal travel, more leg effort. Smaller bore, less volume moved, more pedal travel, less leg effort.

I think what you're experiencing here is that you are using a small bore cylinder, so it takes more travel to fill the front calipers than if you were using a larger bore cylinder. Even with a small bore cylinder to decrease leg effort, the front discs take a tremendous amount of pressure and volume to operate properly, completely different animal than 4 drums. I don't think there is any way you're going to be happy with this system. Use a 'vette master cylinder and 7 inch Midland Ross booster together with the correct valving. Contact these guys:
http://www.mpbrakes.com/

That's just my opinion. I could be wrong.

I agree completely with what the guys have said, and have a couple other thoughts. What bore is your master cylinder? I've never had much luck with the 3/4" or 7/8" and much prefer the 1" (at least) manual master cylinder's, along with what Tech said.

Also, most brake pads and shoes, have a break in process. Might want to check the instruction sheet on the parts you have and see what procedure they recomend.

Anyone who has driven most of their life with power brakes is never going to feel comfortable withougt a booster. It does sound like there is a problem with your system, though. Oh yeah, do you have rubber hoses or stainless braid hoses from the lines to the calipers? Also, anytime the master cylinder is mounted lower then the wheel cylinders, power bleeding is the best way to get the lines full of fluid and get rid of the air.

I think everyone is covering everything, the only thing I can add is to check the adjustment on the rod from the pedal to the master cylinder. If you have a return spring remove it and see your free play. My 2 cents

Thanks for all the replies guys... to be perfectly honest, I'm not sure what the master cylinder is from... i just looked at the Speedway website, and the manual setup they sell looks pretty near like what i have, including the master cylinder. This pic from their website:

http://www.speedwaymotors.com/p/3285...ail-Mount.html


The car was built when i got it, Its a Kilbourne chassis, and I believe that it may have been purchased by the builder with this setup in place, although it would have been taken apart for paint, etc., I say this because when I asked about various components on the chassis such as what type of discs, etc. he mentioned that he bought the rolling chassis from Kilbourne, as well as the body. There is only about 10 miles on the car, so I thought aboutt he "break in" idea, but I have put brakes on my daily drivers many times and didn't need to wait a week to have them work correctly, if you know what i mean. One other thing I might note, is that I have a tile floor in my garage, its waxed and shiny, and i can have my foot on the brake and pull it into reverse, then let off the brake slightly to ease out of the garage, and the front wheels skid across the floor as the back wheels roll... I attribute alot of this to the fact the front tires are timy and the back ones are huge, and the floor is slick, but the front brakes definitely are working, even without a ton of pedal pressure. I'm wondering if maybe the back shoes are out of adjustment and are not grabbing as quickly or as hard as they should? I think alot of it has to do with just not being used to the effort needed to brake without power assist... i just figured a light car like a roadster would have brakes like crazy, and it doesnt seem to be the case... I had a 69 camaro once with 4 wheel drums, no power assist, and it feels similar to that... I may rip up the carpet and try to bleed the brakes, but i really don't think air is the problem, although I'v e been wrong before!

Jack up the back and adjust the shoes so that when you grab the tire and attempt to give it a quick turn and then let go of it with your hand, it will only spin maybe 1/4 to 1/3 turn. Then go for another test run and report back.

Oh by the way, the flex lines from the frame to the calipers are braided steel. Here's the best pic I have on hand of the front brake setup:

Faith said exactly what I was going to say.......I have never had anything but manual drum brake setups, always using pretty much the same '40 Ford front, and whatever came with the rear I was using (generally 8 or 9 inch ford) and my cars stop on a dime and straight . But it takes a good amount of time to get them there, adjusting, testing, readjusting, testing, etc. Some people say these old time components are lousy, I feel just the opposite.

We also complicate things when we build these cars by using a master cylinder from one car, front brakes from another, rear from still another, etc.

With a little work, and maybe substituting some components, like the master cylinder, or residual valves, you will come up with very good brakes.......but like Faith said, never like power brakes, they are two different animals altogether.

By the way, I have used Silcone Dot 5 brake fluid for the past 20 years, and will never use anything else. I get no corrosion in the system, and don't have to worry about my paint getting eaten away. I know lots of people poo poo silicone, but that has not been my experience.

Don

Yup, set up the rear brakes....

Originally Posted by joeybsyc

There is only about 10 miles on the car

This line blew me away. What are you waiting for? DRIVE that thing man!

Originally Posted by SirSpeedy

This line blew me away. What are you waiting for? DRIVE that thing man!

Easy to say when you live in FL..... we are to get another 6 inches of snow tonight.
I would agree adjust the backs and go for a ride when the snow melts.
One thing about bleeding....you should not have to tear up the carpet. The master cylinder should be low enough you can get the top off.
Check level with your finger and use a squeeze bottle and a clear nylon/rubber line to put more fluid in it.
That is what I do...... under the car is a PIA but looks good.