Excessive brake pedal travel

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zdebat
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Excessive brake pedal travel

Post by zdebat » 07 Dec 2010, 18:46

Aro 10/01 1998, 1400 cc petrol engine. Changed brake master cylinder. Large brake pedal stroke, 5 - 6 cm. When you engage the brake everything is fine. What should I do?
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hbogdan
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Re: Excessive brake pedal travel

Post by hbogdan » 07 Dec 2010, 19:07

Did you flush the air from the system?
Aro 10.4 DR, 1995, Renault F8Q248 1.9D, 65CP

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Re: Excessive brake pedal travel

Post by zdebat » 07 Dec 2010, 22:24

There is no air in the system. Checked three times. Auto brakes well, just the height of the pedal is problem.

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hbogdan
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Re: Excessive brake pedal travel

Post by hbogdan » 07 Dec 2010, 22:51

I guess this is the normal behaviour; too little the travel means that one calliper got stuck, there is water in the brake fluid or the master cyl is broken (the pressure is not released from the circuit when pedal is depressed).
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zdebat
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Re: Excessive brake pedal travel

Post by zdebat » 08 Dec 2010, 00:01

Before changing the main brake cylinder, the height of the pedal was good. All cylinders on the wheels are correct and verified. When the pedal is released, the wheel is not braked. Brake fluid is new.

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cristi-devildnb
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Re: Excessive brake pedal travel

Post by cristi-devildnb » 08 Dec 2010, 00:23

did you replaced the servo too? the brake pumps are identical? there is a screw between the servo and the pump. the distance from screew to piston is the same?
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Re: Excessive brake pedal travel

Post by zdebat » 08 Dec 2010, 16:36

Brake master cylinder is not identical to the original. Original has two tanks and the replacement has a one. Servo has not changed. Do you know some measures to adjust the rod between the servo and the pedal? How to adjust?

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Re: Excessive brake pedal travel

Post by cristi-devildnb » 08 Dec 2010, 18:38

if the diameter of the pump is smaller is normal for the pedal to have a longer travel. the original is 23. the distance from the servo screw to the first piston is <1mm. you dont have to adjust the screw between the pedal and the servo if the pedal is up. if you want to do that you remove the bolt and spin the hexagon metal part to the left
http://www.reno.ro/index.php?act=Attach ... 1627459045
Image
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zdebat
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Re: Excessive brake pedal travel

Post by zdebat » 08 Dec 2010, 22:50

I understand the fact of the diameters and volume of brake fluid. After 5 cm, the brake pedal load is operating normally. The problem is if you should suddenly hit the brakes, the stopping up late because before long the pedal stroke. I'll try to adjust the screw between the servo and the brake cylinder.

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Re: Excessive brake pedal travel

Post by zdebat » 11 Dec 2010, 22:50

I got a higher pedal but after 10 km test drive noticed that the brakes are heated. Pedal was higher than before and very hard. Little did I loosen the screw between the master brake cylinder and servo and came home. Now the pedal again lower. What now?

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Re: Excessive brake pedal travel

Post by icemann » 03 Sep 2013, 23:57

cristi-devildnb wrote:if the diameter of the pump is smaller is normal for the pedal to have a longer travel. the original is 23. the distance from the servo screw to the first piston is <1mm. you dont have to adjust the screw between the pedal and the servo if the pedal is up. if you want to do that you remove the bolt and spin the hexagon metal part to the left
http://www.reno.ro/index.php?act=Attach ... 1627459045
Image
hi Cristi,
can you tell me which reno shares the same servo for the brakes.. i have this on the picture and i have to replace it. :(

thanks ^:)^


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