anglia4 Posted October 25, 2011 Share Posted October 25, 2011 Flatmate changed the brake pads in his Toyota Caldina the other day and since then it has had pretty much no pedal. He said he had trouble getting the pistons pressed back into the callipers (he only did the front, has drum brake rear). We bled the brakes tonight and then I took it for a drive. It seems to have good pedal pressure when the engine isn't running, i.e the system is bringing the pads out and pressuring up. But when you are driving the pedal pretty much goes all the way to the floor. Any ideas? Quote Link to comment Share on other sites More sharing options...
JoKer Posted October 25, 2011 Share Posted October 25, 2011 borked the foo foo valve? sometime pressing the callipers back ruptures something in brake booster part of the system, creating air leek or something like that Quote Link to comment Share on other sites More sharing options...
thegreatestben Posted October 25, 2011 Share Posted October 25, 2011 You haven't bled them adequately. Quote Link to comment Share on other sites More sharing options...
anglia4 Posted October 25, 2011 Author Share Posted October 25, 2011 You haven't bled them adequately. Bled the whole lot till I had new fluid at all four corners. and without the engine running (so no vacuum on the booster) it feels good, not like it has air in it. borked the foo foo valve?sometime pressing the callipers back ruptures something in brake booster part of the system, creating air leek or something like that This is what I had wondered since it was fine before he changed the pads and has only gone wrong immediately after. Is anybody able to shed some light on anything specific to do with the booster and any way that it can be checked? Quote Link to comment Share on other sites More sharing options...
kyteler Posted October 25, 2011 Share Posted October 25, 2011 You haven't bled them adequately. This would be my initial thought. Bleeeeeeeeeeding should be started from the furthest from the master, so being RHD it should be LR, RR, LF, RF. Is it ABS? That could be something gay in there also. Quote Link to comment Share on other sites More sharing options...
peteretep Posted October 25, 2011 Share Posted October 25, 2011 is it leaking any fluid? maybe thats getting air into the system Quote Link to comment Share on other sites More sharing options...
Valiant Posted October 25, 2011 Share Posted October 25, 2011 It still has air in the system. Or it has a stuffed master cylinder. Try clamping the the front brake hoses and see how the pedal feels. If it's still low it is the master cylinder. If it feels OK you have a problem with the pads or calipers. It's very hard to say on line with out seeing the car Quote Link to comment Share on other sites More sharing options...
anglia4 Posted October 25, 2011 Author Share Posted October 25, 2011 Had another look at it then, Found a banjo fitting on the front right caliper that wasn't overly tight and looked like it might have been leaking, cleaned it up and tightened it back up, re-bled and still no good. Will have a nudge at clamping the front lines tomorrow night and see what happens then. Cheers guys, keep any ideas/wisdom coming Quote Link to comment Share on other sites More sharing options...
Rhyscar Posted October 25, 2011 Share Posted October 25, 2011 will be air up that system somewhere. think what has happened is kind of what joker described but also modern cars have a trick/stupid proportioning valve that doesn't like fluid/air going through it backwards. they also block up really easily when doing this so its general no-no (not worth it). when pressing piston back in just undo bled valve to stop any fluid going back up the system. best bet is to bleed the bejesus out of it. also bleed rear drums as well cause lines will run diagonally on a caldina. if you go through a whole bottle of fluid when bleeding and its still not working then i'd say you'll have to look a bit further. Quote Link to comment Share on other sites More sharing options...
anglia4 Posted October 26, 2011 Author Share Posted October 26, 2011 Balls! Diagonal lines suck for this sort of crap haha I was talking to my other flatmate who helped him do the pads, apparently the right front piston was pretty much seized, dunno if that would make a difference to air in the system though. I've had a look around the piston and can't see any weeping so I think it is still sealing. Will bleed it some more tonight and see how it goes. Hopefully he will buy me more mcdonalds and feed me more beer Quote Link to comment Share on other sites More sharing options...
Rhyscar Posted October 26, 2011 Share Posted October 26, 2011 taking the sliders out, polishing and using some copper grease on them is always a good idea. do mine every time i change the pads. Quote Link to comment Share on other sites More sharing options...
QCADTA Posted October 26, 2011 Share Posted October 26, 2011 A seized piston will cause this. Had exactly the same problem on the mrs altezza. Freed it up and bak to firm pedal wile drivin. Quote Link to comment Share on other sites More sharing options...
xsspeed Posted October 26, 2011 Share Posted October 26, 2011 Having a similar issue after replacing pads in mrs' caldina last week - I pushed caliper back by way of touge's method above (clamped the brake lines too) Only gave it a little bleed though - so still yet to bleed the whole system (tomorrow night's job) Quote Link to comment Share on other sites More sharing options...
anglia4 Posted October 26, 2011 Author Share Posted October 26, 2011 A seized piston will cause this. Had exactly the same problem on the mrs altezza. Freed it up and bak to firm pedal wile drivin. Seems weird for a seized piston to cause it but he did have trouble with one of the pistons being seized. Perhaps we will check that tonight before the bleed, make sure the piston is moving freely and if not give it a polish. Hope its that simple! Judging by looking at his old pads that right front caliper hasn't been working for a while, the pads are super pitted almost all over with very little actual brake wear. Pads from the other side were down to the steel... Quote Link to comment Share on other sites More sharing options...
KKtrips Posted October 26, 2011 Share Posted October 26, 2011 Make sure the pads are not sitting crooked in the calliper mount and jamming - I have seen this situation when the pads sit skewed and it give a very spongy pedal because it is bending the brake pad rather than pushing it in. Quote Link to comment Share on other sites More sharing options...
anglia4 Posted October 26, 2011 Author Share Posted October 26, 2011 All good things to check thanks guys, keep the ideas coming. Keen to get the bloody thing fixed coz he is borrowing my car in the mean time Quote Link to comment Share on other sites More sharing options...
KKtrips Posted October 26, 2011 Share Posted October 26, 2011 A seized piston will cause this. Had exactly the same problem on the mrs altezza. Freed it up and bak to firm pedal wile drivin. Seems weird for a seized piston to cause it but he did have trouble with one of the pistons being seized. Perhaps we will check that tonight before the bleed, make sure the piston is moving freely and if not give it a polish. Hope its that simple! Judging by looking at his old pads that right front caliper hasn't been working for a while, the pads are super pitted almost all over with very little actual brake wear. Pads from the other side were down to the steel... Re-reading this post the theory of a seized piston in the caliper seems extremely likely. Quote Link to comment Share on other sites More sharing options...
anglia4 Posted October 29, 2011 Author Share Posted October 29, 2011 Thanks for your help guys, particularly QCADTA. Popped out the pistons and gave them a big clean up, one of the pistons was pretty sticky but also the dowels that the caliper slides on were seized. Bled the crap out of it yet again. I haven't driven it but my flatmate says they have never worked so well the whole time he has had it. probably because it only had one working front caliper! Thanks again guys! Quote Link to comment Share on other sites More sharing options...
QCADTA Posted October 29, 2011 Share Posted October 29, 2011 thats awsome mate. always good sort things out like this for yaself. Quote Link to comment Share on other sites More sharing options...
anglia4 Posted October 29, 2011 Author Share Posted October 29, 2011 Yeah man, I'm usually pretty good at figuring out whats wrong but that one had me stumped! Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.