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Discussion Starter #1
Hi So I am working on a 1961 Giulietta ti sedan with drum brakes all around.

It has new shoes, new brake master and new slave cylinders all around. I have bled it with a power bleeder and I am getting no air in the system. I pumped the system up to 7PSI and left it for three days and it did not drop any.
I have adjusted all the drums. I take them down til they lock the wheel and then back off until I have no drag.

But with all of this the brakes are not good. The pedal has too much travel before braking. Once I get to the braking area it does slow down but not phenomenally well.

Also the fronts adjust fine, but I don't like the way the rears adjust.

I have also pulled the lines off at the T connection and plugged them so that I only have the master cylinder and the short piece of line to the T connector. And like this the pedal is solid.

My though is that the drums have worn so much that it is taking to much stroke to fully engage the brakes.

Any ideas

KL Harper
 

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I think your problem may just be that the new pads need to bed in.

Back in the old days, brake shops would arc the pads to the drums: basically spin them on a machine to pre-wear the pads to match the curve of the drum. But I don't think any shops do this any more (at least, I couldn't find one).

If you just install new pads that aren't arced, they're not making full contact to the drum. And they won't until you drive a while, bed them to the drums, and then readjust clearance. In the meantime you'll have really crappy braking (ask me how I know).

So unless you had the pads arced, this may very well be your problem.
 

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My though is that the drums have worn so much that it is taking to much stroke to fully engage the brakes.
No, I don't think that's your problem. Even if the id of the drums has enlarged, if you can adjust the shoes enough to make contact, and then back them off a little, you are compensating for the increased size of the drums.

Admittedly these drum braking systems are "fiddley". A lot of shoes and cylinders need to move before braking actions begins, so the adjusting process is critical. Are you confident that your shoes are parallel to the drum surface - the shoes adjust in two dimensions.

I agree with everything that Gubi wrote. One thing I'd like to add from my own experience with these braking systems: Stopping ability is highly dependent on the shoe lining material. Most local re-lining shops will use the same friction material on a 2,500# Alfa that they would put on a 25,000# dump truck. That stuff has too low a coefficient of friction to stop your Giulietta with reasonable pedal pressure. While re-lining the shoes with a softer material won't solve the long pedal travel problem, it will address pedal effort.

The guru for selecting and applying friction material, arcing shoes, and grinding drums on early Alfas is Brake Materials and Parts in Ft. Wayne, Indiana. See: http://brakematerialsandparts.webs.com/ Yes, you will spend a few bucks shipping heavy parts back and forth, but they will get fixed properly.
 

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I have adjusted all the drums. I take them down til they lock the wheel and then back off until I have no drag.
In addition to the good advice given above:
Check that the shoes operate parallel to the drum.
If you have three shoes up front, they need to be adjusted equally.
Also, you may be backing off too much.
In any case, the brakes are never anything like modern brakes...
 

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Hi KL Harper

Jay, Tom, Dennis and NMS are all spot-on, adjustment, lining material and brake hoses are critical. Brakes on these cars are actually very easy, the 3 shoes are even simpler provided you understand how to adjust them correctly.

I can lock up the 2 shoe brakes on my Giulietta's, (Sprints / Spiders and Ti) on the tarmac if need be, the braking is *that* good, but the choice of lining is critical.

Anything with a woven brass thread (Unless it's the original MZ41 lining from Alfastop in the UK - Welcome to AlfaStop - Suppliers of Classic Alfa Romeo car parts and spares (AlfaRomeo)) will be (as Jay noted), for a light truck with a brake booster and lots of mass.....

We had the same issue with our '61 Ti in that it arrived with new linings, brakes were terrible, I change the shoes for a spare set with a soft 'scooter' lining as the shop calls it and the brakes are great.

Pedal travel is adjusted at the U bracket & push rod at the back of the pedal box - caution here as you need to adjust in 1/4 increments as it's really easy to over do things here & if you adjust things too tightly and block the feed hole from the reservoir, the fluid in the master cylinder is trapped, gets hot, expands and applies the brakes for you.......cracking a bleed nipple will release the pressure and get you going again, but it's no fun if the brakes start to come on when you are overtaking a truck....guess how I know

Best place for bits is Tony at Alfastop.co.uk

Shout if you need more help & pictures, pictures, we all like pictures !!

Ciao
Greig
 

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Discussion Starter #7
Brakes

Hey Guys thanks for the input.

I should say that this is a 2 shoe system and not a 3 shoe. Also the rubber lines have been replaced. The only thing that is not new are the metal lines and the drums.

The shoes either came from Alfa stop or classic alfa in the UK. This is a customer's car and while I have worked on a few 101 and 750 cars brakes, none have given me the problem that this one has. Most of the cars that I work on are 105 and later.

I do think you are on the right track with adjustment and bedding in the brakes. The only adjustment that I am aware of are the two bolts that takes the 18mm wrench on the front for adjustment and the 10mm square on the top of the rears. My plan is to drive it a bit and work the brakes and then adjust it again

Thanks again
Kevin
 

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I'm working on my rear brakes,so thought I'd chime in.Here are some pics of the adjusters(one for each shoe,don't know what the felt bush is for,grease?) that are screwed in or out until the shoes are parallel with the drum.A screwdriver and a 1/2" box or open end wrench are all that's needed for this procedure.Alfa has a tool that bolts to the wheel hub for setting the shoe square(with brake drum off),but a machinists' square will do the same thing.A simpler way to do this(according to Alfastop) is after bleeding the brakes,loosen the adjusters out several turns,apply and hold the brakes(which seats the shoes flat to the drum),and then screw the adjuster in until it just touches the brake shoe,lock in place,release brake.My adjusters were a little loose in the back plate after chasing the threads,so I'm going to use wave washers just in case. I just got my rear brakes and drums back from Brake Materials and Parts.My drums were somewhat clean when I sent them,so all they had to do was cut them.As for the steel rear shoes,they burn the old lining off,clean and remove rust,dip in corrosion inhibitor,and looks like some kind of paint.The non-asbestos woven linings(looks like some copper in there?) are riveted,arced to new drum diameter,and ends beveled.I don't think the rears need beveling,but they're the experts.Turn around was about a week,$166.00 incl. ship to Ga..Oh,plus my shipping cost.Phil D
 

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Brakes

Send your shoes and drums to these guys and they will renew the shoes with the correct material and "arc" them to match the drums.

The rest is just a matter of taking time to do the adjustments.
 

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Brake pedal travel

I agree with AlfistiSA regarding adjustment of the master cylinder piston and seal. If the at rest position of the piston is too far back from the feed hole to the reservoir, then the first inch of pedal travel is simply pushing fluid back up in to the reservoir. And if the feed hole is not exposed at rest, the brakes will lock up when things get warm. The trick is to have the piston seal just slightly behind the feed hole from the reservoir. It's a trial and error process since you cannot see where the piston seal is at rest.
 

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Discussion Starter #12
Hey john,

I talked with the owner and that is where the shoes actually went for this car.

KLH
 

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Hmmm.

Master cylinder bench bled?
 

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Giulietta TI brake problem

Guys,
This is in followup to my Gulietta TI brake problem that Kevin wrote in about. I'd like to add some further info and emphasize some things to see if anyone can help.

Background:
After relining the front shoes and surfacing front drums (Brake Material & Parts, in Ft Wayne), replacing all 4 front brake cylinders, bleeding & adjusting all 4 corners, the pedal height was ok but not enough "grab," even after meticulous bleeding and adjusting all 4 corners. (I know how good brakes should be in a TI, having taken one on the Monte Carlo Historique last year, and then driven it through the Alps with the UK Giuliettta Register in June.) So, we replaced the MC with one from Classic Alfa. I didn't measure it but it looked like the old one.

Problem - little or no pedal after replacing master cylinder. Air in lines despite repeated bleeding.

Observations - Front cylinders do move out under gentle pedal pressure. Front shoes appear "square" and fit well in drums after relining. There was no apparent air in lines before replacing MC, and the lack of "grab" may have been due to the new shoes.

Tried:
Adjusted stroke of MC to specs.
Ran “gallons” of fluid through the lines, with no air bubbles.
Meticulously bled all 4 corners, with shoes in, with shoes locked to drums, and with shoes correctly adjusted.
Blocked off the MC output line at the T-junction – got good pressure at the MC, good solid pedal with no leaks.
Pressurized the system to 7 lbs and held it for 3 days with no leak down.

Further observations: After all the above, the pedal went almost to the floor, with marginal braking, and would not pump up. I then bled all 4 corners, and found air in both front and left rear cylinders. I continued to get air despite extensive bleeding. After all this, there was NO pedal at all.


Thoughts. We think it has an air leak and when we pressurize the system it seals, but it seems that the air is being pulled into the system when the pedal is released.

Questions:
Is the problem in the new MC or in the fitting thereof? Where else could air be coming from?
Also, is it easier to remove the pedal assembly to replace the MC? It's a bear to get off otherwise.

Thanks,
Don
 

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Weird.

Don,
You have air present in the system, but no sign of leaking fluid?

The Giulietta MC is notoriously hard to rid of air after re-fitting. Bench bleeding is a must (Went through this on a '61 Spider recently).

Might try suction bleeding, too.:whistling:
 

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Don,
You have air present in the system, but no sign of leaking fluid?

The Giulietta MC is notoriously hard to rid of air after re-fitting. Bench bleeding is a must (Went through this on a '61 Spider recently).

Might try suction bleeding, too.:whistling:
Thanks, John. Tell me about suction bleeding.
Don
 

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Might be a little late for this little gem.....there is a tool which allows you to adjust the shoe faces to be parallel to the axle with the drum off. Tore Nieddu makes these in the UK and it changed my long pedal to short pedal immediately. It also allows the drum to slip on easily with new linings in place.
 

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A vacuum/suction bleeder attaches at the caliper or wheel cylinder to your air compressor. With the compressor on and the nipple open a vacuum is created that draws fluid (and hopefully air) through the line. It has the same advantage as a pressure bleeder in that, with the MC piston in the resting position, the supply port is exposed in it and fluid is drawn all the way from the reservoir. This allows for a better purge. It's a good way to move alot of fluid through the lines in a short amount of time.

Some have had success using both pressure and suction on the same car. This worked for me. But only after removing the MC and bench bleeding it. Apparently the Giulietta system, due it's shape, is very good at trapping air in pockets.
 
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