Brakes fading...advice needed!

manatoo

Hi all

I have been the happy owner of a 1995 Carina E for the last 6 years and 80,000 trouble free miles.

Unfortunately at the advanced age of 16 years and 140,000 miles on the clock it finds itself at somewhat of a crossroads. It's NCT is due early next year and I'm a little concerned about it's chances of passing given that the brakes are gone a little soggy. In it's last NCT test it only scraped through the brake force test with a score of 55% (limit is 50%) and it has definitely gotten a little worse since then. I do all servicing myself and as much as I like the old barge I'm not stupid enough to pay big money to get any big job done to a car I bought for 900 quid 6 years ago so unless someone here can advise me of a quick, cheap and easy way of beefing up my brakes a bit I fear she will fall to the crusher and a scrappage deal Renault Fluence will grace my driveway instead. Since the scrappage scheme ends at the end of December I have to make a decision on this.

I know it's not the pads/shoes because I changed both of them recently. The brakes have never been bled since I bought it cos I dont know how to do it. Lastly, the discs and drums are in reasonable shape, I don't think replacing them will help much

Any thoughts or advice to save the old girl??

Thanks

Darsad

manatoo wrote: »

The brakes have never been bled since I bought it cos I dont know how to do it. Lastly, the discs and drums are in reasonable shape, I don't think replacing them will help much

I think you just gave the answer there my friend !

mathepac

You have the answer in the other thread - brake-fluid is hygroscopic, get it changed ASAP.

Nissan doctor

The brake fluid should be changed roughly every 2 years, if this has never been done then this is where to start.

Next would be to check the condition of your flexi brake lines, as these will be aged and possibly begining to expand when you press the pedal.

You say the disks are in reasonable condition, have you measured their thickness against factory tolerances? If the disk has worn too thin it will overheat very quickly and cause brake fade.

Rear brake cylinders can also weap fluid and lead to a soft pedal.

manatoo

Nissan doctor wrote: »

The brake fluid should be changed roughly every 2 years, if this has never been done then this is where to start.

Next would be to check the condition of your flexi brake lines, as these will be aged and possibly begining to expand when you press the pedal.

You say the disks are in reasonable condition, have you measured their thickness against factory tolerances? If the disk has worn too thin it will overheat very quickly and cause brake fade.

Rear brake cylinders can also weap fluid and lead to a soft pedal.

The pedal isn't soft and there's never been any fluid around the cylinders so I'm pretty sure it isn't any of those things but there just isn't as much bite in the brakes when you hit them as there used to be. Again bear in mind it's a Carina with crappy disc and drum setup and the brakes were never exactly earth shattering but they definitely used to be stronger than they are now.

No, I've never measured them against factory tolerances but I've never ran the pads down to the metal or anything that would cause them significant wear

Nissan doctor

manatoo wrote: »

The pedal isn't soft and there's never been any fluid around the cylinders so I'm pretty sure it isn't any of those things but there just isn't as much bite in the brakes when you hit them as there used to be. Again bear in mind it's a Carina with crappy disc and drum setup and the brakes were never exactly earth shattering but they definitely used to be stronger than they are now.

No, I've never measured them against factory tolerances but I've never ran the pads down to the metal or anything that would cause them significant wear

That has nothing to do with the disks wearing or not, if they are the original disk with the milage you have then they will be significantly worn.

Mr.David

Yeah, check the discs for wear you'll see if theres a 'lip' at the outer edge.

140,000m on original discs is massive! I've just changed a set of front discs after 28,000 miles!

salamander27

Sometimes if there is wear on the discs such as a lip around the edge or grooves in the disc face the contact area for the new brake pads is significantly reduced thus affecting the stopping power. The old pads would have worn into the grooves and would have had better contact so check them for wear. Pads should be changed with discs.

I'd definitely bleed out the old fluid though. Just for piece of mind. A bottle of dot4 cant cost you that much and it's easily done with a clear tube and a jar. Just be careful not to let the reservoir empty.

Balbriggan mechanic

If thats still running the original fluid then it definately needs to be changed. The fluid probably consists of about 70% water at this stage. Changing the fluid is easy. Buy a litre of dot 4 brake fluid (don't be tempted to use fluid you may have sitting around as this will probably be as bad as the stuff in the car). Open the fluid resevoir and fill up to the top. Now get an empty 500ml drinks bottle and about a foot of clear plastic tubing (ask the motor factor for a foot of windscreen washer tubing when you're getting the fluid). pour some clean fluid into the bottom of the bottle, just enough to cover the end of the tube. Now start the operation at the wheel furthest away from the resevoir. Beside where the brake pipe enters the rear drum assembly there will be a small bleed nipple usually with a small rubber cap on it. On older high mileage cars these can be quite corroded so a good tip is to give it a couple of gentle taps with a hammer to free it before trying to open it with a spanner. Connect the pipe to this nipple, open it about 1 turn and have a helper pump the brake pedal. Remember to keep an eye on the fluid level in the resevoir as you don't want to pump air into the system. Keep pumping until the fluid in the pipe looks clear and has no air bubbles in it. Close the nipple but don't overtighten it or it will snap off. Repeat the procedure for the other rear brake. The front brakes are bled in the same way and the bleed nipple should be clearly visable on the side of the caliper. Once you have all 4 corners bled check and make sure you have a good firm pedal and top up the resevoir. A point to note is if the car has ABS brkes fitted the bleeding procedure should be carried out with the engine running otherwise air may become trapped in the ABS unit. Hope this helps