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View Full Version : Brake Caliper right rear problem



weaselciuy
01-19-2011, 06:03 AM
Hello

I`m loosing brake fluid where i marked on the pic, its my rear right wheel.

Do i have to buy the entire caliper or can i fix it with a caliper repair set ( i see they sell those also) .

I have brakes as long as i keep my fluid tank full. It looses about 0.25ml at 2km drive/braking in city.

What is that nut i encircled, it has 2 small holes likes a needle punctured it, and sprays liquid when i press the brakes.

Problem is i dont understand anything in there except where the brake pads are :/

Help please, new caliper is about 150$...

http://img524.imageshack.us/img524/9956/etrierdreaptaspate.jpg (http://img524.imageshack.us/i/etrierdreaptaspate.jpg/)

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walky_talky20
01-19-2011, 10:19 AM
It looks like where the brake line connects the caliper. Have you tried to tighten it a bit. You might try loosening it 1 quarter turn, then tightening it again. Sometimes that will help it reseal.

zrowcool
01-19-2011, 01:38 PM
i would go with what walky said. also theres some copper washers that go in there on both sides of the hose. try swapping them out for some new ones. if its not the actual bolt but the hose/crimp then you can just change the brake hose for like 30ish bucks. if the caliper isnt seized and applies the brakes, i dont see why you would need to replace it.

weaselciuy
01-19-2011, 01:42 PM
so let me guess: the upper cable is the handbrake cable, the other one you say is the brake hose transferring fluid and that`s where its making a connection.

I found caliper repair kits all of them coming with a bunch of seals, bolts and those 2 metal things that appear to hold a hose at one end, let fluid out the other holes.

http://img153.imageshack.us/img153/4928/mysampleimage.jpg (http://img153.imageshack.us/i/mysampleimage.jpg/)

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I`m gonna take apart the whole assembly tomorrow (if the weather permits).
No i didn`t try anything yet, just located it. I`ll try it tomorrow before removing, who knows :P .

Anything i should look out removing the rear calipers, taking in account the handbrake is there also. Can i put it back alone or do i need some weird special VAG tool that you don`t find in your everyday car toolbox.

btw thanks for the answer...builds my moral :)

walky_talky20
01-19-2011, 03:27 PM
There is a special tool that is needed to wind the caliper piston back in. You can borrow this tool kit from Auto Zone, though (with a deposit).

I couldn't remember if the rear calipers used a flange type fitting or a banjo fitting with crush washers. If it uses crush washers, then you can replace them to fix the leak. If it is just a line fitting, then you just need to tighten it a bit more.

walky_talky20
01-19-2011, 03:44 PM
Ok, just did a little research. ETKA's photos of the rubber brake lines in question do not show this line very well. Firstly, the quattro and frontrak cars have different rear brake setups, lines and all. The quattro cars use a metric thread line fitting on each end, no washers. The Frontrak cars (like the OP's) have a weird right angle block/fitting on the caliper end of the rubber line. It appears to be a banjo fitting style and requires 2 copper crush washers. Unfortunately ETKA fails at life in explaining this and doesn't offer any dimensions or part numbers for the washers. Your best bet would be to take the washers off the car and go and match a replacement pair at a hardware store. They don't have to be perfectly exact, just reasonably close.

If it is just leaking from this connection, I think a new caliper is definitely unnecessary.

weaselciuy
01-19-2011, 06:18 PM
ok, tomorrow i`ll take them off, clean them and see what i can do about the leak problem.

I also found that the piston needs to be pushed back, but i heard with a little help from 2 screwdrivers it will go back in.
Anyway its important i fix the leak, i can get a friend to come and help me reassemble it back if i run intro trouble but he`s very busy untill sunday.

Will go buy new brake lines anyway with this occasion cause they are kinda old ( i think they are OEM), i replaced only front this summer.

weaselciuy
01-20-2011, 05:11 AM
ok, i went out, dissasembled everything and i found out its the damn brake hose. Those mechanics are worthless, last time i go to them for advice, only for dirty work and do what I TELL THEM from now on.

Its this hose, the metal end made them think its the caliper i think, i dunno. I actually retighten it and it doesnt loose fluid anymore. I just ordered 2 of them + new screws and will go mend the whole thing myself.
Its the first time i work around brake system so i was a little scared to go down there :p .... now i know whats all made off...

Goddamn useless mechanics here in my country, really.

If anyone by any chance come here and have car problems, dont ...DONT go to a mechanic or workshop.

http://img227.imageshack.us/img227/4928/mysampleimage.jpg (http://img227.imageshack.us/i/mysampleimage.jpg/)

Uploaded with ImageShack.us (http://imageshack.us)

Thanks for the help and God Bless !!!

EDIT: btw i just found out what you were meaning with the BANJO fitting :)) yeah thats the one i need.
Thank you :)

Btw whats the difference between Lucas TRW and ATE Brake systems. I take it my car has Lucas...??

walky_talky20
01-20-2011, 07:04 PM
Was it leaking from the hose, or just the connection where the hose connects to the caliper? If you tightened it and it stopped leaking you are all good now, yes? No need for new lines if it was just leaking at the fitting.

Lucas, TRW, and ATE are manufacturers and OE suppliers for many vehicle brands. All the calipers should be the same, though. I believe the B5 A4 brakes were all made by ATE.

weaselciuy
01-21-2011, 06:00 AM
it was leaking from the conection. The whole sealing was absed on high torque on the bold, using 2 metalic rings (dunno how you call in english). It worked untill today, it seems to be leaking again, altough less, more of a drip now.

I still dont understand completly how fluid from the BANJO thing goes trough that bold, it completely blocks the small hole of the banjo thing. Maybe that bold also has a hole somewhere and it needs to be aligned. I`ll see when hoses arive.

I wana change them i dont want any surprises on long trips outside hometown.
I asked whats with the Lukas and ATE thing, since every1 keeps asking me what i have. I went ahead and told them its Lukas :p ....hope you are right and they are the same .... just a brand thing.

Also gonna upgrade my ABS pump the same day.

walky_talky20
01-21-2011, 07:17 AM
Usually the caliper manufacturer is cast into the caliper itself so you can read it right on there. Perhaps in your county there were multiple rear brake setups. In the US I believe there were only 2 for the A4, 1 for quattro and 1 for frontrak. ETKA lists only 1 part number for that brake hose on the frontrak.

There isn't any alignment on the banjo fitting. The inner part of the hole has a machined spherical relief. So the fluid will pass all around the bolt shaft. That relief is connected to the flow from the hose. So the fluid from the hose enters the relief and is pushed through the hole(s) in the side of the bolt shaft and then out the end of the bolt. It is important that the surfaces seal which is why 2 "copper crush-washers" are used. One between the bolt head and the banjo, and one between the banjo and the caliper. It is also important not to over-torque the banjo bolt. It is hollow and is not as strong as a normal bolt the same size. But it does need to be tightened enough to "crush" the copper washers for a good seal.

weaselciuy
01-21-2011, 07:40 AM
ok, i`ll remember that when i change them. I guess i`ll do it myself, since i dont think i have to bleed the system just for this. The ABS Pump is not dry, always had minimum in worst case.

I`ll have to inspect the new hose hope it comes with new bolts also, they didnt have MEYLE anymore (with bolts) so they gave me ATE ones but hope they come with bolts and seals, i was half asleep when they called me.
I guess no rubber seals were used cause the system is under high pressure, i`ll see about the torque, will have to do some testing after i`m done experimenting as a DIY mechanic.
Thanks for the help, will get back if anything weirder happens.

weaselciuy
01-22-2011, 02:45 AM
stupid dealer sent me wrong hoses; i told them exactly several times "BANJO" with a big metal end with a hole in it. I got the typical hose...
Now got to wait until Monday.

Happy day :p