Loss of breaking pedal-pressure

[lepperd]

Hello everybody! Ths is my first post, and im sorry about my English:-)

Ive had some problems with my breaks on my corola 98 lately. The breaking pedal seems to suddenly, from time to time to loose its pressure. Its like the pedal almost goes straight down to the floor with very little breaking effect - and i have to lift the pedal once before it works as normal pump it).

This has happened three or four times now, and the pattern is that it happens either if i drive for a while (typically through long tunnels without using the breaks) or after heavy breaking usage down hills.

Its a very uncomfortble experience and it makes me hesitate to drive. Ive tried to google others with the same problem, but i havent found any with the exact same problem. 

I hope anyone knows what i am talking about.

And thanks in advance!

Tor

[oldcodger]

Hi,

Are you are not loosing any actual brake fluild from the sysytem / having to top up the master cylinder reservoir ?

If not then I would think its a faulty master cylinder and / or the flexible brake hoses expanding under heat /pressure.

For a car nearly 20 years old I would think both need replacing anyway with new parts.

You might have to search for a master  cylinder as have seen others looking for them , though thats in the UK, not sure where you are .

[lilpopjim]

Like oldcodger said briefly, you most definitely have a master cylinder fault etc. There's a few o-rings in the shaft inside the master cylinder. When you apply the brake the preasure causes the fluid to seep past the failed o-rings which of course, looses pressure in the system.

I'd get it swapped out asap. 

Hop onto eBay and look for a 98 corolla breaking in your area.

[oldcodger]

12 hours ago, lilpopjim said:

I'd get it swapped out asap. 

Hop onto ebay and look for a 98 corolla breaking in your area.

Hmmm... so you would be happy to drive your car fitted with an 18 year old second hand , unkown condition, scrappers brake master cylinder ..??  ....  I think not ..

As the most important part of the braking system, think new is the only safe option.

 

[lilpopjim]

You't buy it from a breaker with good reputation. They don't want bad business so they normally test parts before sale; they have a business to run remember.

Here's a BRAKE master cylinder: http://goo.gl/L6nU58

 

EDIT: removed the 2 links i put for clutch master cylinder. Oops!

[TomdeGuerre]

That's a clutch master cylinder you have in your second link so that won't work.

I'd sometimes prefer to go for a 2nd hand genuine M/Cyl rather than some of these rebuilt eBay specials with their dodgy seals.

[lilpopjim]

Oops.. It pays to read the title.. I completely missed it.

But yes, you're right. Personally i'd go with a genuine part off an old car rather than, as you put it, an eBay special.