Me vs. Brakes: The Road to a Solid Pedal Options

[bkrantz]

If the pedal never seems firm enough, check to see if the MC is flexing (rotating down at front) when you stand on the pedal. Some MC mounts are weak enough to flex, and prevent full transfer of pedal force into hydraulic pressure. If it flexes, then try adding a brace.

[iankarr]

You've gotten great advice in this thread. Also important to keep in mind that it's normal with these cars/calipers for it to be a bit of work to get firm pedal when the system is fresh. There are literally dozens, if not hundreds of threads about trying to get a hard pedal. Just to summarize, in order (with a few things that have worked for me)...

– "Bench Bleed" master cylinder if not already done (see video in my signature for how)
– Replace rubber lines
– Ensure venting clearance is correct
– Replace bleeders with speed bleeders
– Use a motive pressure system AND stomp on the pedal (this is where the speed bleeders really help)
– Repeat bleeding 2-3X
– If pedal is too soft to drive, crack the fittings on the regulator and pump pedal (closing after each pump) to get air bubbles out. Can also tap with a hammer.
– If pedal is STILL too soft, try using a syringe to shoot fluid through the bottom bleeder, with the upper one open. This forces stubborn tiny bubbles out.
– Take the car for a bumpy drive
– Bleed again
– Bed the pads
– Pedal will not be rock hard for about 100 miles or so...until the seals loosen up.

Hang in there!

[wonkipop]

You've gotten great advice in this thread. Also important to keep in mind that it's normal with these cars/calipers for it to be a bit of work to get firm pedal when the system is fresh. There are literally dozens, if not hundreds of threads about trying to get a hard pedal. Just to summarize, in order (with a few things that have worked for me)...

– "Bench Bleed" master cylinder if not already done (see video in my signature for how)
– Replace rubber lines
– Ensure venting clearance is correct
– Replace bleeders with speed bleeders
– Use a motive pressure system AND stomp on the pedal (this is where the speed bleeders really help)
– Repeat bleeding 2-3X
– If pedal is too soft to drive, crack the fittings on the regulator and pump pedal (closing after each pump) to get air bubbles out. Can also tap with a hammer.
– If pedal is STILL too soft, try using a syringe to shoot fluid through the bottom bleeder, with the upper one open. This forces stubborn tiny bubbles out.
– Take the car for a bumpy drive
– Bleed again
– Bed the pads
– Pedal will not be rock hard for about 100 miles or so...until the seals loosen up.

Hang in there!

that pretty much describes my experience back in early 2020 after laying the car up for 16 years. (IMG:style_emoticons/default/biggrin.gif)

and even then its not a firm pedal like modern cars. i think part of it is its meant to be a little soft so you can use your foot with a bit of sensetivity? ....... and not lock up rear brakes. the old proportioning valve thing? dunno. but mine will pull up pretty good and pretty straight with a firm stand on the pedal. but its firm---ish and the pedal goes down. a ways.
they are actually pretty good brakes,,,,,,,,for 1969.
try a type 3 VW from the same era and count the number of circles you do if you stand on the brakes with the same force. (IMG:style_emoticons/default/beer.gif)

[Bwingate]

You've gotten great advice in this thread. Also important to keep in mind that it's normal with these cars/calipers for it to be a bit of work to get firm pedal when the system is fresh. There are literally dozens, if not hundreds of threads about trying to get a hard pedal. Just to summarize, in order (with a few things that have worked for me)...

– "Bench Bleed" master cylinder if not already done (see video in my signature for how)
– Replace rubber lines
– Ensure venting clearance is correct
– Replace bleeders with speed bleeders
– Use a motive pressure system AND stomp on the pedal (this is where the speed bleeders really help)
– Repeat bleeding 2-3X
– If pedal is too soft to drive, crack the fittings on the regulator and pump pedal (closing after each pump) to get air bubbles out. Can also tap with a hammer.
– If pedal is STILL too soft, try using a syringe to shoot fluid through the bottom bleeder, with the upper one open. This forces stubborn tiny bubbles out.
– Take the car for a bumpy drive
– Bleed again
– Bed the pads
– Pedal will not be rock hard for about 100 miles or so...until the seals loosen up.

Hang in there!

This is pretty much how I will be spending Memorial Day weekend - little does my wife know she will be recruited. I have front calipers and stainless brake lines on order from PMB, so I will have to redo the process once they arrive.

I have a Motive and speed bleeders - love them both. I am in the habit of changing out brake fluid every year, so they make the job super easy.

@iankarr : I've seen most of your videos. They are quite helpful - thanks for the work.

[emerygt350]

Although the stock brakes will never have the grab we are all used to from modern (even moderately modern cars) I have to say, on the track they are really a different beast. At least on my car. I remember the first time I late braked into turn 1 at the Glen and ended up with a huge smile on my face and new-found confidence in my 50 year old brakes. You just need some strong leg muscles.

[moto914]

late braked into turn 1 at the Glen and ended up with a huge smile on my face and new-found confidence in my 50 year old brakes

Hopefully that will be the case soon with my lower powered light weight track car.

[Bwingate]

Finished up the job this morning and I think I found my problem right away: leaky switch. The master cylinder is in fact new (had a QR code on it) but the switch just needed a 1/8 of a turn or so. Pedal felt firm afterwards, but I went through a round anyway. Popped the little nub back in an now the brake warning light works correctly too.

Now I'll have to go through this again in a week or two once my new front calipers come in

[emerygt350]

Great to hear it. I had my son pumping the brake for me this morning and we made some real good progress. I think this must be the 3rd bleed since last August and finally all the air is out. I had him really put the pressure on when we did the rears. Didn't see much for bubbles but the pedal is better than it has ever been. I really think you have to drive the crap out of it and bleed it again and again.

Speaking of that, what size are the stock front bleeders? I always end up using a vise grip.

[emerygt350]

I just reread your post... The switch shouldn't leak at all... You can replace it without losing fluid. I thought you were talking about the valve in the back.

But hey, if replacing it helped, awesome! I need to replace mine, it doesn't really work.

[Bwingate]

<<snip>>eaking of that, what size are the stock front bleeders? I always end up using a vise grip.

Mine were 7 and 8 mm. I replaced them all with speed bleeder which are 8mm.

I just re read your post... The switch shouldn't leak at all... You can replace it without losing fluid. I thought you were talking about the valve in the back.

But hey, if replacing it helped, awesome! I need to replace mine, it doesn't really work.

Didn't need to replace it. The switch was just a little loose.

Brake bleeding has to be my least favorite routine maintenance tasks.

[emerygt350]

<<snip>>eaking of that, what size are the stock front bleeders? I always end up using a vise grip.

Mine were 7 and 8 mm. I replaced them all with speed bleeder which are 8mm.

I just re read your post... The switch shouldn't leak at all... You can replace it without losing fluid. I thought you were talking about the valve in the back.

But hey, if replacing it helped, awesome! I need to replace mine, it doesn't really work.

Didn't need to replace it. The switch was just a little loose.

Brake bleeding has to be my least favorite routine maintenance tasks.

It wasn't leaking from there right? That area should not have fluid in it.

[Bwingate]

<<snip>>eaking of that, what size are the stock front bleeders? I always end up using a vise grip.

Mine were 7 and 8 mm. I replaced them all with speed bleeder which are 8mm.

I just re read your post... The switch shouldn't leak at all... You can replace it without losing fluid. I thought you were talking about the valve in the back.

But hey, if replacing it helped, awesome! I need to replace mine, it doesn't really work.

Didn't need to replace it. The switch was just a little loose.

Brake bleeding has to be my least favorite routine maintenance tasks.

It wasn't leaking from there right? That area should not have fluid in it.

"There"? The switch itself wasn't leaking, the connexion to the master cylinder was not right. Just had to tighten the switch a bit

[emerygt350]

Not the switch. The place where it goes, there should not be fluid in there, it sounded like there was.