Gearbox Cutch CVs - Clutch slave-cylinder
Introduction
Note some of this information is out of date and after market parts are now available from brickwerks including the flexible rear pipe to the clutch slave and 6mm hard pipe and unions
There are at least two different configurations of slave cylinder pipework from master through chassis to slave. When some of the metal parts corrode or break, it can be difficult to work out exactly what you need, source the parts or carry out the work. However, There is now enough information around to short-circuit soem or hopefully all these problems...
Please use the links provided below to the 80-90 Tech Archive topics
ClartsOnly: The difference between the pre '86 clutch slave cylinder pipes. the pre '86 is a flexipipe, a bracket and a solid "brakes pipe" the later upgrade is the £18 plastic pipe from the clutch pipe on the chassis directly to the clutch slave.
Baxter's Brickwerks sells some clutch operating system parts now difficult to obtain from VW..
Pipework Explanation
Simon Baxter The clutch pipe union is M12x1. The clutch pipe is 6mm, not 1/4" as your local place will try to sell you. 1/4" pipe does not fit 6mm unions.
Hacksawbob This pipe common to all front to back pipes goes over the fuel tank and tank removal makes removal and refitting easier but not necessary. Remove the front union then cut the pipe. Replace in two sections with the Brickwerks repair kit. This will need a flare putting on the pipe. The repair kit doesn't come with the front union and is intended for rear section replacement but with some foresight and a request they could put a flare and a union on the tail end of the supplied clutch pipe. If you are replacing the rear section, inspect closely the front section. It is likely to need replacing and the movement of the pipe when changing it over will show up any marginal rusty pipes elsewhere.
Fuel tank in situ If you are not using the original route over the fuel tank you will need to be creative and use some metal with rubber P clips to support the pipe through which ever route you take. If your van has a rear air blower console between the front seats this will allow a self tapping screw to go up through the floor without protruding as a sharp thing on the floor of your van. Alternativley a round headed bolt could be dropped down from above and covered with carpet it shouldn't be too obvious.
Slave cylinder explanation
These can fail, rust badly, have sheared off bleed nippes, get blocked (so won't bleed out) etc
Often the slave cylinder condition comes into question after the Master Cylinder fails, is replaced, and then th system cannot be bled out, slave investigated, piepwork breaks or comes under scrutiny..
Not a problem to leave with an inexperienced garage (time and money), older experienced well-equipped garages should be able to cope..
Fitting yourself The bolts for the slave cylinder are accessible but awkward from the engine bay especially if rusted solid (spray from road wheels) heat, plusgas and persistence will help greatly stubby 13mm spanner on the under side and socket on the top. When you have rotated the top bolt enough to lock the spanner aginst the bracket maintain the force and you can then get both hands on the socket to apply proper force. Grinder/dremmel is the last ditch solution and great care must be taken not to damage rubber hoses in the area. Some time spent putting tin foil over hoses to protect from heat or gaffer taping some hardboard may prevent further tears, on petrol engines be very aware of fuel lines in the surrounding area. When replacing the rear bolt which is harder to get to, first loosely fit the front bolt and nut from under the van. Then use a strong magnet placed on top of the slave and bracket in place, as you push the bolt up from below, the magnet will hold the bolt in place while you get to the engine bay, pass your fingers to the underside of the bracket and hold it in place while you remove the magnet then get the nut and washer on the top, 13mm M8 bolts 30mm long are required 8.8 tensile strength recommended.
Useful Forum Posts
Aidan: You have been sent one for a syncro, which has a banjo connection at the slave cylinder to facilitate swap outs because of the worse access.
The rear pipe for the early hydraulic set up, eg. CU and other aircooleds is no longer available from VW
The pipe for the waterboxers chassis number D 0000001 to F 079999 is 251 721 479 C and is £27 plus the vat from VW (asof 2007)
The pipe for the early Diesels upto F 079999 is no longer available.
The pipe for the Diesel F 080000 is 251 721 477 J and is £14 plus vat from VW
This same pipe is used on the later Waterboxers, as well as the Diesels
Both use a connecting hose 251 721 477 D from the fixed line and this is £24 plus vat. (asof 2007)
Hope this helps
Why don't people ask VW first - stuff is still available, a lot of it has come down in price recently too, get it now while you can
sendiw: Well done Clartsonly
251 721 477J is definately the right part replacement for the old metal/rubber clutch hydraulic pipe. I fitted it today.. no problem. Give yourself a big pat-on-the-back.
A tip for separating the flexihose from the front line pipe without damaging the front pipe. File an 11mm spanner to 11.5mm and use that with a little persuasion on the front pipe union, if you use a 12mm it will round off and you will probably have to replace the entire front pipe. Don't turn that union just hold it and unscrew the flexihose from the union.
That done... if the union is seized on the pipe, use a blow lamp on it and allow it to cool. It should free off. It needs to be free to screw into your new replacement part. Well it worked for me!
