Front Caliper Piston Retractiom

bbrucez · Post by **bbrucez** » 04 Sep 2005, 06:03

I know front pistons need to be turned as I managed it on my BX many times.
However, my C5 has defeated me so far, in fact the piston has come out more and I can't even get it back to as it was.
It's far bigger than the BX and won't budge although is not seized. Managed to turn it (both ways) with an air filter tool but levering it in draws a blank.
Car is now undriveable until I sort it. Help!!

Clogzz · Post by **Clogzz** » 04 Sep 2005, 18:29

You probably will have to wait for the opinion of the experts on the subject, but I would say that the fluid prevents it from going back in.
Maybe opening the bleed screw to release some fluid will enable it to go back in.
Check for burrs on the metal from using the filter tool.
The burrs would need smoothing, otherwise the piston may bind in time.

406 V6 · Post by **406 V6** » 04 Sep 2005, 18:34

The braking system on the C5 is a convencional vaccum-servo assisted one.
This may sound silly, but, is the hand-brake on?
I wouldn't open the bleed nipples. Did that once on the 406 and luckily that saturday a Precision center was open to bleed the brakes.

bbrucez · Post by **bbrucez** » 04 Sep 2005, 20:12

Thanks chaps but the problem persists.
The oil filter tool has rubberised webbing so no damage done.
Have tried releasing the bleed screw to no avail.
Handbrake is off - I couldn't have removed the caliper if it wasn't!
Maybe I need to buy a special tool - hate to admit defeat.

macaroni · Post by **macaroni** » 04 Sep 2005, 21:19

Is the handbrake on the front on a C5? If not, it shouldn't need turning.
If so, I had a right hard job doing that on my Xantia. I turned it 3 or 4 turns, then used a separating tool to push the piston bakc slightly, then a few more turns etc, etc. It took ages.

AndersDK · Post by **AndersDK** » 04 Sep 2005, 22:24

According to the schematics on Citroen PR-net the C5 handbrake is working on the front calipers. The way the handbrake cables are connected is not seen as they are hidden on the rear of the calipers shown.
Also there are no exploded view of the caliper internal parts.
The problem then seems to be like <font color="red">macaroni</font id="red"> describes it.

wheeler · Post by **wheeler** » 05 Sep 2005, 00:13

there are 2 special tools to wind back C5 front calipers as both of them wind back in different directions.

bbrucez · Post by **bbrucez** » 05 Sep 2005, 05:35

Yes, the pistons have a 5mm hole in the middle and 2 slots either side - probably to receive the tool.
I assume I can get the tools at GSF? The investment should be cheaper than taking it in to the dealer.

Post by **Sir Clive** » 05 Sep 2005, 13:43

Just did this job on my C5 last week! I bought a piston retraction tool from ebay, it slots into the piston, and then you just put a socket on to turn it. If you turn the piston the WRONG way, it comes out to its limit, and you think 'Oh s*%£, I've broken it!' All you have to do is turn it the other way, and it will go back in, but it does take while before anything happens, and you do need to push as well as turn. The pistons on each side turn in opposite directions.
You don't need to release the bleed nipple.
Hope this helps.
Regards
Philip

bbrucez · Post by **bbrucez** » 05 Sep 2005, 14:54

Thanks - things are looking up!
Found Item number: 7997352849 that does AUDI FORD HONDA JAGUAR MITSUBISHI NISSAN ROVER SUBARU SAAB TOYOTA VW but doesn't mention CITROEN. Is yours like this?

Post by **Sir Clive** » 05 Sep 2005, 15:02

The thing I got is a steel disc, with pins on one side to engage the slots in the caliper piston, and a hex on the other side for a 12mm socket. Simple but efferctive

Regards
Philip

bbrucez · Post by **bbrucez** » 05 Sep 2005, 15:29

Thanks Philip,
A colleague has got one similar to the Ebay one which I'll try tomorrow.
Does yours push the piston while it turns?

AndersDK · Post by **AndersDK** » 05 Sep 2005, 15:30

http://www.franklin-tools.co.uk/ got the special tool TA896 for C5.
However Philips' tool seems easy to copy as DIY [;)]

bbrucez · Post by **bbrucez** » 05 Sep 2005, 19:06

I asked Franklin if I needed one for each side and they said "maybe - will let you know".
Found similar to Philip's on toolbay.biz but can't work how it does both sides.

Post by **Sir Clive** » 05 Sep 2005, 19:17

The tool itself, in effect, enables you to turn the piston with a socket and rachet handle. Just set the rachet for the direction in which you want to turn the piston, and you can do both sides with the same tool.
Regards
Philip