MR2 Roadster Owners Club

The Workshop => Maintenance, Problems & Troubleshooting => Topic started by: adam p on March 9, 2015, 11:42

Title: Unresponsive brakes
Post by: adam p on March 9, 2015, 11:42
I have no idea what make of discs or pads are on my Roadster, but there is very little wear on the discs, front pads have plenty of pad and the rear pads are brand new. Brakes have been bled twice but the brakes are really spongy and the brake pedal needs to be pushed about half way down before the car even begins to stop. I've had a couple of people nearly pull out in front of me and it's a good job they didn't because I wouldn't have able to stop. When I know I need to stop at roundabouts etc then they do stop really well, it's only the initial response which is lacking. All the other cars i've driven the car begins to stop right at the top of the brake pedal. I presume there is a fault with the braking system or front pads?
Title: Re: Unresponsive brakes
Post by: Wabbitkilla on March 9, 2015, 12:30
Possibilities;
Vacuum leak for master cylinder, check the vacuum feed from the intake manifold to the master cylinder.
Master cylinder failure.
Weak and worn out brake flexi pipes to the calipers.
Title: Re: Unresponsive brakes
Post by: adam p on March 9, 2015, 12:58
Ok thanks. I've already taken it to a local garage who couldn't find any fault with the brakes, so i'll take the car back to him and get him to check the items you have suggested. Should it be easy enough for a garage to diagnose do you think?
Title: Re: Unresponsive brakes
Post by: StuC on March 9, 2015, 13:04
Have they checked the pads by looking from the outside or by getting right in there?
I only mention it because the inner pad generally wears faster than the outside one, as the piston acts against the inside pad. Also, the inner disc face is harder to see because of the shield on the inside face. The inside face is usually showing more signs of wear that the easy to see outer one.

To demonstrate the point here is what happened on mine at the rear.
(http://i204.photobucket.com/albums/bb158/StueyC07/MR2%20Banana/Maintenance/DSC_0410.jpg) (http://s204.photobucket.com/user/StueyC07/media/MR2%20Banana/Maintenance/DSC_0410.jpg.html)
Plenty of pad on the outside pad, nothing on the inner pad... AT ALL!  s:shock: :shock: s:shock:
Title: Re: Unresponsive brakes
Post by: adam p on March 9, 2015, 13:39
No he just had a look from the outside. I'm really hoping it is this so at least I can kill two birds with one stone and get the pads upgraded at the same time. I'll show him this photo too  s:) :) s:) . He's having a look tomorrow so i'll let you know.
Title: Re: Unresponsive brakes
Post by: StuC on March 9, 2015, 14:19
Yup, let us know.  :-) :-) :-)
Title: Re: Unresponsive brakes
Post by: GT4-Play on March 9, 2015, 14:23
If your looking for upgraded pads and it discs and braided lines, please do send me a message or ask for a price  s;) ;) s;)
Title: Re: Unresponsive brakes
Post by: adam p on March 10, 2015, 18:25
Ok all fixed  s:) :) s:) . The mechanic had the car for 1.5 hours checking the brakes out and was found to be one of the slider pins in the caliper had seized. The other one on the other side wasn't much better either. He took them out, cleaned and lubricated them and the brakes are soooo much better! The pedal is right at the top and they are a bit too responsive now lol. I've got a caliper slider kit coming so he said to pop the car back in when it comes as he thinks cleaning and lubricating the pins is only a temporary fix. The brakes on the mr2 are awesome!
Title: Re: Unresponsive brakes
Post by: men3cac on March 10, 2015, 19:39
Mine seemed to have gone a bit south recently as well, with the odd ABS intervention when I wasn't expecting it. Just been out and stood on them hard a couple of times and they seem to be back to their usual selves- wondering if my sliders are starting to stick a bit too, seems a common fault.

Glad you fixed it, I think I'm going to have to get the spanners out again
Title: Re: Unresponsive brakes
Post by: gazza1286 on March 10, 2015, 20:02
Adam - glad you got the brakes fixed BUT what on earth did your mechanic do the first time when he told you they were fine? He obviously didn't check even the basics.