Yesterday, while on the road my brakes got softer and softer and ultimately I could not stop on time for a 4-way-stop as the brake pedal went to the metal. Only after pumping 3 times or more would it still brake a bit. Driving about 15 - 20 mph, and having my surprisingly useless handbrake ready (new pads), I made it home. I checked the break reservoir: there were small particles on the filter, but otherwise it was full. There was no puddle of oil. I ordered a new reservoir and brake master cylinder. So I will put those on first. I think it would be wise to drain the system first.
The question is, how do I drain the brake/steering system to replace the fluid?
Thanks!

 

There's no relationship between brake fluid and power steering fluid....so no consideration there.

There is no drain, per se, for the brake system. The reservoir and master cylinder can be emptied when you remove them. The remaining fluid in the system is pushed out during the brake bleeding process.

Cheers
DD

 

Brake fluid is hydroscopic in that it absorbs water from the air. If your brake fluid is old and has absorbed water, your brakes will have those symptoms when the water in the fluid starts to boil. If your brakes returned to normal after cooling down, this could be the cause.

 

daanv,

What makes you think it needs a new master cylinder? As you mentioned that the car had been laid up for some time, there could be a number of reasons for a soft pedal, including air in the system, absorption of water in old fluid, even a leak somewhere.

I definitely wouldn't fit anew m/c yet. I would do a full flush of the system first, then check the state of the calipers and brake lines. I'd also probably replace the flexis as well.

Good luck

Paul

 

Thanks for the consideration! I will get to work at that. Too bad, I already ordered the part, but maybe I should just keep in on the shelf for now.
The steering had been squiking a bit also and was not as easy as a while ago.
Thanks for the great advice.

 

Assuming a non ABS car, it definitely needs a new M/C! Make sure you fit the new one, say I.

If you do, it can be difficult ot get the fluid primed and pumping through it properly. What I do is to connect up the new one to the reservoir, but do not connect the outlets to the two pipes to the calipers. Then fill the reservoir and get someone to pump the pedal to order. Ask the helper to push the pedal down and hold it down, then place a finger over each outlet and ask the helper to release the pedal. Repeat a few times until fluid pumps out and then connect the pipes. This procedure prevents the new M/C pulling air back into itself rather than fluid from the reservoir. Place some rags under the M/C to ensure no fluid spills onto the bodywork.
When bleeding, start with the rear opposite corner and pump through until new bubble free fluid comes out. Then the other rear caliper, then the front opposite and finally the one nearest the M/C. You have inboard brakes and the rear nipples are difficult to get at.

Excuse my making this point if you already know, but if you have never bled brakes before, it is best with two people, one on the pedal and the other under the car doing the nipple. Make sure you can loosen the nipple and attach a piece of clear plastic pipe to it, make a loop in the pipe with the free end into a container. The purpose of the loop is so you can see bubbles or not in the fluid coming out. Your helper presses the pedal to order AND HOLDS IT DOWN while you simultaneously loosen the nipple just enough for fluid to come out. Do up nipple and only then tell helper to release the pedal. Keep repeating until clear bubble-free fluid comes out. BUT ensure the reservoir does not run out of fluid, so regular topping up and checkin,g mlevel is vital.
The bleed nipples can be very hard to loosen, make 100% sure you have a small ring spanner of the correct size.

 

I had not understood that from the comments. Will replace them and report back at the results.
Tx

 

All of which means the M/C rubbers will be toast Paul!

 

Hi, I am not sure what rubbers. Do they come with the M/C or should they be ordered seperately. I just ordered the M/C on Partgeeks, but did not ask for rubbers.

 

I was referring to the rubber seals inside the M/C. These will be already inside the new one, so no worries!

 

Thanks all for the great advice! We started checking the entire system, and found out that the rubbers of all the calipers were in bad shape, as well as one of the brake lines. The garage where I was originally had said upon my request that all the brake fluid had been replaced. They lied! it was totally brown and full of little particles. Also the plastic reservoir was toast. So I now have a new brake system that works great. Only one thing remaining: the brake light on the dashboard remains on, while the pressure gauge indicates that the brake pressure in totally fine. Any suggestion?

 

Please clarify what you are referring to.

There is no dashboard gauge for brake pressure.

Cheers
DD

 

From memory your car is an '87, yes?

You should have two warning lights on the dashboard for brakes. One for the parking brake and one for the main brakes. Which one remains lit?

Cheers
DD

 

If you mean the brake warning light, maybe the float switch in the reservoir is faulty.

 

Sorry, you are right. I was confused. The brake light is ok, but the oil light is on, all the time, while te oil pressure gage indicates normal pressure levels. Moreover, the fuel level gage has a problem: it never went higher than 3/4 and now it does not come up at all, most of the time. I monitor my fuel with the milage.

 

The oil warning light sender is most likely not working, ot the wire has come off and is grounding. It is sited at the rear of the V on a cast aluminium pedestal, along with the guage sender next to it. The smaller of the two is the warning light sender.
It is hard to get at and removing the throttle capstan and its pedestal makes the job far easier. You MUST support the pedestal against the undoing torque of your spanner (with a pair of grips or something similar) when you change the sender, or you will break off the casting and that is a disaster.



The fuel guage sender is easily got at, it is halfway up the fuel tank behind the spare wheel. Ensure you have no more than 1/4 tank of fuel and it can be easily changed for a new one and the circuits tested.