Brakes, what am I doing wrong?

[8ob]

try cracking off the bleed nipple, if the wheel then turns there is pressure in the brake pipes/hoses which maybe the hose has collapsed internally

This would be the first thing on the list after a clean up, has proven to be the problem on more than one occasion on our trucks.

Bob

 

[daedalusminos]

I would get new discs and pads...if you must then keep those pads for the next change.

 

[Nomad]

Could I just carefully grind the lip of the disc or is that going to throw it out of balance?

I found no problem after taking the lip off the outside using an angle grinder, if not done the new flat pads only make contact on the raised inner & outer lips on the disk, so very little contact area until they bed in.

The wheel should turn fairly freely without needing to use a wheelbrace to turn it. One thing not mentioned yet, check where the pads fit in the caliper - often the machined surfaces that hold the pads have corrosion which stops the pads moving freely, clear with a file or wire brush.

Lots of good advice already in this thread, to get good working calipers the options are free off the ones you have, or strip them and fit new bits (piston & seal kit?) or replacement calipers. A lot depends how important your time is, and how badly yours are worn. Good luck

 

[tom2207]

I prefer to crack the bleed nipple before pushing the pistons back in , its better to get rid of the excess fluid out of the caliper at the bleed nipple , couple of reasons pushing fluid back through the system can cause issues , most times it wont , but it can
it gets rid of the old fluid too , if a calipers been sticky the fluid may have suffered from excessive heat / being boiled . and it gets rid of fluid that is probably past its sell by date any way .
Cracking the nipple also lets you know how much of the wind back pressure is caused by the piston and not the seals in the master cylinder and restrictions in the lines ,[ try blowing through a garden hose ]
Also lets you know how much bother you will be in if you need to replace metal pipes or flexible hoses , if the nipples crack easily your pretty much ok to swap out whats needed , if they dont crack stop before you break everything and cause lots of grief , usually on a saturday , just after the parts shop has closed , but at least you can plan your new calipers or a complete strip.
But those discs are past their best , as are the pipes and at that point id bung flexis on it and close it up for the next few years .
two rav 4 discs cost 20 quid the pair last weekend , thought that was a great deal , and the new bits please the mot boys , half the jobs done at that point.

 

[carbon]

Those discs will be below the minimum thickness if you remove the lips from them. Think I paid about £40 each for vented ones for my T5 from tps last year.

 

[Bryan Williams]

More woes.. According to the Brakes International and GSF there are two discs that fit the van, one 282mm dia, (mine) and one at 260mm dia, so went to GSF, got them home, thought they looked a bit thicker but thought well they are well worn on the van.
Tried one on, on tightening up the caliper it fouls.
No one mentioned disc thickness.

 

[frank horton]

I use one of these......

will do car/med truck disc's n drums...also m/cyle drums n discs with the wire wheels mounted....
mostly cos I do vintage stuff.......
most disc's will skim 50 thou no probs......but disc's are now pretty cheeeeeeap......
hard to know what to buy other than high end makes as a lot come from China the repackaged !!!!!!!!!!!......
ALSO a lot of the cheaper new disc's are machined when the cast iron is still GREEN, so they warp a little after a few hundred miles....had that a lot......

 

[tom2207]

didnt see that one coming ,, measure the old discs right at the edge , the outer edge where the lip that isnt worn away and is still at the full thickness and see what it is , gives you an idea of how thick it started out

 

[Bryan Williams]

Just did what I probably should have done in the first place. Tightening the disc on with the five wheel nuts..
It's not catching now but there's only a mil or so clearance is that right?

 

[tom2207]

as long as its not catching it should be grand , check the caliper and the pads fit on nicely before you start bolting it all together too , gets something else out of the equation later on , lets you know the piston is back far enough.

 

[Cobbler]

Looking at the photo, it looks like the disc slot is built up with corrosion, i so I would take it off & clean it off with a file.

 

[Pigeon_Droppings2]

Check the caliper and pads fit back on....clean up the caliper carrier too as previously suggested.

Don't feel bad....I did exactly the same thing. Volvo use 2 sizes of disc....I got all the way to putting on the caliper and pads too and though hang on something looks very odd here ....it turned into quite a job that one...a lot of foul language as I had bought the parts a few months previously! In my loft there is a nice new pair of undersized v70 discs....one day I might have use for them ...they are next to the v70 front suspension arms....which don't fit an XC70 (who knew!)

Looking at the originals to me it looks too tight....the wear on the originals won't be on the edge so I would have thought the new/old edge thickness would be similar?

 

[Bryan Williams]

Looking at the photo, it looks like the disc slot is built up with corrosion, i so I would take it off & clean it off with a file.

I had it in the vice, scraping and filing at it.

 

[Bryan Williams]

Check the caliper and pads fit back on....clean up the caliper carrier too as previously suggested.

Don't feel bad....I did exactly the same thing. Volvo use 2 sizes of disc....I got all the way to putting on the caliper and pads too and though hang on something looks very odd here ....it turned into quite a job that one...a lot of foul language as I had bought the parts a few months previously! In my loft there is a nice new pair of undersized v70 discs....one day I might have use for them ...they are next to the v70 front suspension arms....which don't fit an XC70 (who knew!)

Looking at the originals to me it looks too tight....the wear on the originals won't be on the edge so I would have thought the new/old edge thickness would be similar?

I thought that, I'll measure them with my aldi digi calipers just so I can say I've used them.., although if they are the original ones, I suppose the edges are going to corrode away as well.

 

[Kayos]

Discs, pads and even calipers are cheap in the grand scheme of things, if they looked like that on my van I'd just replace the lot

 

[Pigeon_Droppings2]

Discs, pads and even calipers are cheap in the grand scheme of things

Yup...but so are brake pipes, suspension struts, springs, boots, top mounts...all cheap as chips....until you add them all together

 

[carbon]

Two discs available as you say 282 x 18 for vans with 15" wheels and 260 x 16 for vans with 14" wheels

 

[Bryan Williams]

Two discs available as you say 282 x 18 for vans with 15" wheels and 260 x 16 for vans with 14" wheels

Yeah 282,two for £48,just working my way through the jobs, I know the brake pipes are rough, replaced a couple already, hand brake cables, the shoes looked OK but the little t retainers needed replacing, but now I'm doing the discs I'll get drums and shoes.
Spent a bit on my fiesta lately , cam belt, front springs, two tyres, two back tyres for the van, so just doing things a bit here and there as I can afford it..
Got a mig welder coming Monday hopefully so I'll be attempting to set fire to the van soon as well.

 

[Pigeon_Droppings2]

Got a mig welder coming Monday hopefully so I'll be attempting to set fire to the van soon as well.

You can't just throw that in there without telling us what welder you've bought....so we can discuss in detail for a few pages

 

[Bryan Williams]

You can't just throw that in there without telling us what welder you've bought....so we can discuss in detail for a few pages

It's a pre loved (hopefully) Clark 151en turbo.
Can't wait..