Bleeding Brakes

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Moose21
Posts: 2
Joined: Wed Apr 17, 2019 2:04 am
Dino: Fiat Dino 2.0 Spider

Bleeding Brakes

Post by Moose21 » Wed May 08, 2019 10:15 pm

Hi, I am a new member from New Jersey that inherited a '67 2000 first series from a dear friend who had owned it for over 25 years. I have owned it for the last 10 years. This site is great and has proved useful to me over over the years for help and information when tackling issues. This time I have a question that I would like to ask the forum. Three years ago I replaced the master cylinder, and what a job that was. I replaced the flexible hoses and went to bleed the brakes. After failed attempts, life went on and the Dino sat idle for 3 years. Fast forward, I went to tackle the brakes again. The first time I used the hand vacuum pump to no avail. I have seen the newer methods of reverse bleeding, but most kits have a capture tank that would screw onto the reservoir tank, which would be impossible on the Dino. I have searched the forum and found nothing about brake bleeding and looking for input on what other members have done to bleed the system. I have minimal braking in front and nothing to the rear brakes. Has anyone had any luck with the reverse bleeding and if so, what have you used.

Thank you in advance

Moose21

Dario
Posts: 84
Joined: Fri Nov 29, 2013 12:18 pm
Dino: Fiat Dino 2.4 Coupe

Re: Bleeding Brakes

Post by Dario » Sun May 12, 2019 7:34 pm

Welcome to the forum! I have rebuilt my MC and commiserate in the pain of getting it out and back in, it was probably the worst job I have done ever. However, I had no problem in bleeding the brakes afterwards. Started at the rear right, then rear left, front right and finally front left. FYI, there are two nipples on each of the front brakes, one for each of the two lines.
If bleeding does not work, you might want to try to block off parts of the system to isolate the problem. Did you pump the brakes before filling with brake fluid? If the MC was not lubricated before, you can easily score the rubber grommets. The rebuild kit works fine, but it requires removing the MC :shock:

good luck,
Dario

Dinoswede
Posts: 63
Joined: Sat Apr 05, 2014 4:22 pm
Dino: Fiat Dino 2.0 Spider

Re: Bleeding Brakes

Post by Dinoswede » Mon May 13, 2019 12:41 pm

The 2 Litre Dinos´ front calipers only have one air nipple each side, not two, as on 2,4 Litre Dinos.

Many years ago, I tried using silicone-based brake fluid (CARTEL), and it was a complete disaster!
It gave a brake pedal sinking into the floor mats before any braking power applied, and I bled and
bled the system many times, totally in vain.
When I finally flushed the whole braking system with "ordinary" DOT 4 brake fluid, I instantly got
perfect brakes!
So, if anybody is thinking about using anything but DOT 4 brake fluid, my advise is- don´t!

Dinoswede

Moose21
Posts: 2
Joined: Wed Apr 17, 2019 2:04 am
Dino: Fiat Dino 2.0 Spider

Re: Bleeding Brakes

Post by Moose21 » Tue May 14, 2019 6:42 pm

Dario and Dinoswede, thanks for the feedback. I used a reverse bleeder to pump the fluid from the calipers back to the reservoir tanks. I started at the rear passenger and ended at drivers front. All the fluid from each caliper pushed back into the passenger side reservoir only. I did not get any fluid pumped back to the driver's side reservoir. If I understand the setup, the passenger side reservoir should be for the front brakes and the driver side for the rear. Something is diverting the rear brakes to the passenger side tank where it should push it to the driver's side. So what am I missing here?

I would hate to have to take the MC out again. :cry:

thanks again,

Moose21

User avatar
Tobi
Site Admin
Posts: 340
Joined: Thu Nov 14, 2013 7:56 am
Dino: Fiat Dino 2.4 Coupe
Location: Upper Palatinate - Bavaria

Re: Bleeding Brakes

Post by Tobi » Tue May 14, 2019 7:03 pm

I'm not sure about calipers with no bleeding valve, but don't you bleed them by opening the brake line connection a bit?

Dinoswede
Posts: 63
Joined: Sat Apr 05, 2014 4:22 pm
Dino: Fiat Dino 2.0 Spider

Re: Bleeding Brakes

Post by Dinoswede » Tue May 14, 2019 9:38 pm

Toby, I probably was using the wrong terminology - all brake calipers at 2 Litre Dinos have
air bleeding valves. ("Air nipple" is probably not a correct term, at all. But, in Swedish, it is
called just that - "luftnippel" !)

Moose21 - After having looked at pictures of the master brake cylinder, I am far from
convinced you can use the reverse bleeding tool of yours. I think you still will have a small
air-pocket in the MC, if using that type of tool.
I suggest you do the air bleeding the traditional way, with a helper pumping the brake
pedal slowly while you bleed one caliper at a time, and adding brake fluid in the brake
fluid reservoirs, when needed.
Concerning the brake fluid reservoirs - they actually are connected to each other with a short
rubber hose. The connection is placed so when brake fluid is very low in one of the reservoirs,
brake fluid is filled from the other reservoir - but - only to a certain level. This design is to
stop air getting into any of the two braking circuits (if you have a leak somewhere), "as long
as possible".

Dinoswede

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