Hi All
I have a VW Golf 1300 Mk2 82,000 miles.
After a few minutes driving and going over 60 mph I hear an intermitent high pitch noise from the front of the car. After this time the noise can sound at lower speeds. It also occurs whilst in neutral.
A mechanic has briefly heard this and he says it is the brake calipers possibly seizing, possibly due to brake dust. This results in contact with the disc thus giving the noise. The seizure is therefore occuring as the wheels warm up.
From reading similiar problems I believe the cause is due to front brake calipers possibly seizing, possibly due to brake dust.
How do I fix this problem? Do I just remove the calipers and brush off all the brake dust? Do I fit new \"retaining springs\"?
The pad thicknesses are well above the min.
If it\'s not the calipers could it be a warped disc?
Thanks
Andrew
|
|
Anyone?
|
|
Andrew,you want to get this sorted quickly. If a caliper is seized it can cause quite severe localised overheating, even causing the road wheel to get hot. Get a Haynes manual and it it should be evident what could be binding. Out of true discs tend to judder but you can check this with a suitable dial guage. I don't know the calliper arangement on your car. Mike.
|
|
I think its a 'Collette' type caliper, isn't it? Remove bottom slider bolt and swing caliper upwards. Then extract the pads and clean the pad contact surfaces in mounting bracket. Put a spot of copper grease on the steel pad backing where it slides in the bracket and reassemble. Haynes manual will guide you.
|
|
|
|
had this apart on my mk2 on tuesday. the sliders can seize making the brakes bind. Try tkaing the sliders out (the two big bolts with allen head fittings) and greasing them (copper grease if you've got it). Also they say that copper grease on the back of the pads helps too.
I had a lot of difficulty getting the bolts out. If desperate try hammering (carefully) a 12mm socket onto the end of the bolts, tkaing care not to damage the rubber sleeves
|
Sliders themselves should not sieze unless the rubber bellows are damaged (in which case buy new bellows, they are cheap). Use HMP brake grease on the slides. You can actually buy a little overhaul kit that includes bellows and grease.
Important place for the copper grease is on the 'edges' of the metal backing of the pad when it slides into the caliper carrier. For the back of the pad you can buy a VW anti-squeal paste, its not expensive.
|
useful tip on the edges of the pad backing, don't think I put any grease on these.
re the sliders fine, I replaced the lot while I was there: metal sleeves, rubber sleeves (bellows?), plastic inserts as well as the piston seal and dust cover.
the rubber sleeves were a bit patchy but the piston seals were fine
|
Thanks for your comments.
I have cleaned out the brake dust on the front driver side wheel brakes (pads, caliper, etc). I have applied copper grease to the pad backing where it slides in bracket and where it contacts with the calipers.
Unfortunately this did not work as after a drive the intermittent high pitch noise occurred around 50 mph. With reference to ?Mikey Jay? comment I noticed that the front driver side wheel was a tad warmer than the front left (putting hand on outer metal rim).
Also the outer brake pad thickness (driver side wheel) was 13.5mm whereas the inner brake pad thickness was 15mm. Both pads are of the same age. For the other wheel the pad thicknesses are both 15mm.
No brake fluid loss has occurred.
Are the sliders the guide bushes and sleeves that the caliper bolts go through. Should I replace these?
Any thoughts welcome.
|
the sliders are the metal caliper bolts themselves, the inner half of the caliper slides on these. The sliders consist of a bolt with a metal sleeve around the bolt (though this will probably have seized on the bolt - not a problem).
Check these sliders are straight and have no 'roughness' on them.
the sliders pass through the rubber sleeves. Inside the rubber sleeves there is a plastic 'liner' to reduce friction. when the calipers move it is the metal sleeve (the slider) that moves against the plastic sleeve liner.
So check these all look smooth and in place.
Also, the piston is pulled back slightly when you release the brake by the rubber piston sealing ring (I think) which is supposed to seize slightly against the piston bore.
this might have perished, but I doubt it as the one I replaced on my golf on Tues was in perfect nick despite its 14 years.
|
|
I'm wondering if maybe you have a dodgy wheel bearing?
|
|
hmm yes. Does the noise change in volume or pitch depending on whether you're turing left or right or how sharply / fast you are turning?
|
I don't think turning left or right makes any difference. The intermittent high pitch noise sets in after I have reached 60 mph on a dual carriageway and will stay at any speed thereafter, i.e. 15 mph and when reversing.
I thought bearings only give out a drumming noise ( not high pitch).
Does the fact that the brake pads (driver side wheel) having different thicknesses (inner 15mm, outer 13.5mm) mean that the brake caliper is seizing?
I phoned VW dealer, they said best to replace caliper, (costs £55)?
|
yeah, I think the original brake seizure dignosis was right then. My near-side bearing went and the noise was like gentle grating when turning right and silent when turning left.
the symptoms of my brake seizure sound exactly the same as yours
hot wheel hub
execess pad wear (compared to other side)
squeal at high speed
There's a chap on the performance VW magazine site called Andrew Ensom who offered me new (but non VAG) calipers for 20 quid a side if you're interested. I would have bought them but I'd just spent 55 quid on parts from VAG to refurbish my old ones.
Replacing all the working parts was suprisingly fiddly actually, not sure I'd recommend it unless you're confident about having the tools and the patience to work out the best way to fit all the bits
|
So you renewed a wheel bearing, that must of been difficult?
Whats the VW magazine site called? Whats VAG?
Will a non VAG brake caliper have the same dimensions, spec?
Surely replacing a new caliper is nothing compared to replacing a wheel bearing?
|
I am going to push out the sliders (metal sleeve that surrounds the brake caliper bolts) and grease them.
Do I grease the inside and the outside (the outside being where it contacts with the plastic sleeve)?
Do I use copper grease or HMP grease? Where do I get HMP grease?
|
got someone else to do the bearing, I'm not that....... enthusiastic!!!
I'm not sure that taking the sliders off the bolts will help as the metal sleeves are not supposed to move on the bolts. the moving surface is betwent he metals sleeves and the plastic inserts
just as another point, on my golf the squeak has not gone despite all the work done last week (very depressing) so I'm trying to find out about a servo fault causing the binding or bearing probs
as to grease, don't know what HMP grease is I used copper grease and greased the outside of he metal sleeve, but then again it didn't work!!
cheers
|
www.performancevwmag.com
is the site
VAG is the vw audi group ie \'proper\' car parts
couldn\'t comment on suitability of the calipers but Andrew E will know as he seems to know everything about vw brakes
|
|
|
|
