Hi, i have had a few odd/scary moments today with my brakes.

I over applied them on a steep hill this morning, and they got very hot and very smelly and completely useless, was very tricky to stop in time! So i pulled over, let them cool and went on my way. All seemed fine after that. Now I'm getting a squeak from the n/s front i think and the brakes are fluctuating between being very good and very bad. I had the front up, wheels off and discs and pads are fine. Wheels spin freely and don't seem to have rubbing at all. I have now noticed hat when I'm idling stationary and fully apply my brake pedal the car idle changes and almost seems to want to stall as i lift off the pedal. The h/brake warning light has in the last 4/5 weeks popped on and off but just gently wiggling my lever solves it immediately. checked all lines for leaks - none. not lost any fluid. brake booster and master seem fine visually. I believe to check the booster you start the car with the pedal depressed? is this right? when i do, the pedal drops slightly more when i do?

Sorry for the long post, i just want to explain the symptons. Any ideas at all?

NOTE: My pedal is very very firm and has no give in it at all

Overheating the pads can cause a glaze to form on the surface of the pad. This can wear away again in time but it's much better to stick a new set of pads in for the sake of a tenner

It also sounds like the brake fluid level may have gotten low and air may now be in the brake lines.

The design of the brake fluid reservoir is slightly floored so can seem like it's full when it's actually low which is why the light is coming on.

Basically if I where you I'd give the brakes an overhaul and renew the brake fluid.

nathanshenton said:

I over applied them on a steep hill this morning, and they got very hot and very smelly and completely useless,

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No hill should cause this. New pads, of a decent manufacturer should be a high priority. Pagid form Euro Car Parts are decent.

Hi, the fluid level is fine. I jiggled the film thing in the reservoir so the fluid correctly settled before checking. Where it then settled half way between min and max. i then topped up with fresh dot4.

I would assume air in the system would cause a soft pedal? whereas this is very hard. too hard if I'm not mistaken. Am i right in thinking if the master cylinder is gone this will again cause a soft pedal, whereas if the booster is going/gone this will cause a firm pedal? Will the brake warning light alert to problems with pressure aswell as just the handbrake and fluid level?

i may aswell put in some fresh pads, and I will be renewing the fluid completely tomorrow but i just want to know how i can check the quality of the master cylinder and booster? is there some checks i can make to rule out issues with these?

Im sure i read somewhere about the brake booster using a vacuum from the engine? I'm not familiar with how they operate. I changed the head gasket, water pump, cam belt and rocker cover gasket, inlet and exhaust gaskets 2 weeks ago - could i have affected that in anyway?

portland_bill said:

No hill should cause this. New pads, of a decent manufacturer should be a high priority. Pagid form Euro Car Parts are decent.

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Yes, i will be replacing pads anyway, it can't hurt to.

portland_bill said:

No hill should cause this. New pads, of a decent manufacturer should be a high priority. Pagid form Euro Car Parts are decent.

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I did this once
You can cook the 8v's solid disks quiet easily espically if the rear drums aren't fully adjusted and not working as they should

i did it once when i was a noob - car loaded to eye balls, i was speeding between speed bumps (good distance between)

Before i realised it, i'd cooked the brakes
Not knowing what was wrong - it took ages to stop

On the way home - they'd cooled after been at event
But were still naff

Ziggy

Ziggy122 said:

I did this once
You can cook the 8v's solid disks quiet easily espically if the rear drums aren't fully adjusted and not working as they should

Ziggy

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Hi Ziggy. Yes, was a bit tricky to slow the car enough on the steep windy hill i was on. I just slowed as much as possible without brake and used what little brake i had near the bottom to pull over and stop!

The handbrake holds the car fine - could there still be an issue with the rear shoes and drums when it is working as it should?

Whats the likely hood the discs could be warped? I didn't really want to replace front brakes as they both have plenty of life left.

I'd imagine changing the fluid would be recommended now then? Is there an order you bleed the brakes through? Or just do one at a time.

You start furthest away from master cylinder working closer

Cant remember order tbh


Boiled brake fluid = water boiled
So a change is very much pointed


Ziggy

Sounds like there could be a brake dragging somewhere, rears especially suspect. Doesn't take much to boil the fluid after a few miles - yikes no brakes.Let it all cool down and hey presto brakes again.

Brendan W said:

Sounds like there could be a brake dragging somewhere, rears especially suspect. Doesn't take much to boil the fluid after a few miles - yikes no brakes.Let it all cool down and hey presto brakes again.

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Thanks. I think I'll change the fluid and get the wheels and drums off to check everything. Yeah, no brakes, was a first for me! Hah. Be sure to use the engine next time I'm on a steep one.

If you have a draggy brake one hub would be noticeably warmer than it's opposite number. Over tightened handbrakes will boil fluid as well after a few miles even if only slightly dragging.

years ago i changed head Gasket on a Cortina (yes i know that is'nt a Fiat) and forgot to reconnect the vacuum pipe.....no brake assistance pedal was hard to push and not much brake power (well basically no brakes!). since you said you changed the head gasket i'm wondering if you missed reconnecting something....

nathanshenton said:

Im sure i read somewhere about the brake booster using a vacuum from the engine? I'm not familiar with how they operate. I changed the head gasket, water pump, cam belt and rocker cover gasket, inlet and exhaust gaskets 2 weeks ago - could i have affected that in anyway?

Click to expand...

years ago i changed head Gasket on a Cortina (yes i know that is'nt a Fiat) and forgot to reconnect the vacuum pipe.....no brake assistance pedal was hard to push and not much brake power (well basically no brakes!). since you said you changed the head gasket i'm wondering if you missed reconnecting something....

Scudmonkey said:

years ago i changed head Gasket on a Cortina (yes i know that is'nt a Fiat) and forgot to reconnect the vacuum pipe.....no brake assistance pedal was hard to push and not much brake power (well basically no brakes!). since you said you changed the head gasket i'm wondering if you missed reconnecting something....

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Yes, I thought this could be the case! Fortunately it all seems OK now. Apart from an annoying offside front brake squeek! I'll strip it down and try an figure it out. Thanks!