Clutch Bearing Assembly Issue

[TexasR400]

I have resumed my long-stalled Caterham R400 build, and I'm having an issue bleeding the clutch.  The slave cylinder appears to leak from the rear of the assembly.  I thought I might have a bad bearing assembly, so I purchased another with the same results.

Is there a gasket or seal that belongs between the bearing assembly and the spacer that attaches to the bellhousing?  I don't currently have anything between the bearing and the spacer, and I'm wondering if this is my issue.

Here are the relevant parts with part numbers from Caterham.  I'm installing this with a Quaife sequential box.  Standard chassis.

- Clutch Bearing Assembly - Ford Duratec & VVT Sigma (38Q006A)
- Spacer - Clutch Slave Cylinder - Duratec 08/2010 (38Q010B) 10mm
- Bellhousing - Duratec R400 (210hp) (38Q005A)
- Clutch Plate - C400 & CSR260 Race Sequential (37Q012A)
- Clutch Cover Plate - DURATEC (58136COVER)

Please let me know if I can provide any additional details.  I appreciate the help.

[7 wonders of the world]

Have you checked the installed clearences as there have deen several spacers and some do not position the CSC in the correct postion either allow insufficient clearence to allow for clutch wear or encouraging over extention.

Ideally you need to do a dummy build mounting just the bellhousing on the engine allowing you to check the dimension from the clutch fingers (where to bearing contccts) to the mounting face in the bellhousing for the CSC with the spacer.

When installed the CSC is loaded onto the fingers with a light spring as it runs in full contact all the time but it needs to be able to move rearward a further 4mm as when the clutch wears the fingers too move rearward.

I will see if I can find the diagram of this I have.

The new CSC's dont like being compressed dry either, 

The 'overextension' can be controlled by fitting a clutch stop in the pedal box though, initially set it short initally then adjust untill the clutch clears to allow correct gear selection. BM if you need a photo of the set up I use.

[7 wonders of the world]

Here you go

http://www.rwdmotorsport.com/downloads/hydraulic_release_bearing_kit_instructions.pdf

You can use a .7 master cylinder not problem (I do) but you MUST run a clutch stop, pedal weight is fine but you get a nice short stroke.

[TexasR400]

Thanks!  My kit does have a clutch stop.  I'll adjust it as you described.  Just for context, this is a new kit from Caterham that I bought back in 2010.  My build was put on hold for a variety of reasons (kids, job, etc.).  However all of the parts are new from Caterham, and they have confirmed in the past that I have the correct spacer.  What makes this tricky is that the slave cylinder is typically installed in the bell housing from the factory.  (mine was not)  As such, there isn't a lot of documentation out there on the exact assembly and I don't see many build blogs that address these parts.

On the Caterham site, I see a seal that looks like it would drop into the back of the slave cylinder and fit between the slave and the spacer.  The part is "Clutch Cylinder Piston Seal - 1.5"", part number 58168.  But the part description references "CSR", so I can't tell whether this is applicable to my situation (R400) or not.

I appreciate your explanations of how the slave operates.  Perhaps there is no required seal between the slave and the spacer, and I'm just doing something wrong on my end.  Was hoping I was simply missing some rubber bits.

[7 wonders of the world]

Are you sure its brake fluid thats leaking and not tranmission oil..?

 

[Alan Reeves]

I’m not techy but....when I built mine the slave cylinder leaked when bleeding it . Engine out and it appeared that the slave sat on a round spacer? That spacer had an indentation for the slave to sit in, 1 or 2 mm deep. It appears that under pressure it did not sit  square and hence under pressure ended up leaking. Engine out and a chat to CC , never happened before and a new slave and...yep a new spacer with no indentation to sit the slave in.

the old 10 mm spacer has marks 380010B, 2010/11 kit, 5 speed Ford gearbox which may make this all superfluous info.

I have a picture if you want, msg me your email address

Alan

 

[TexasR400]

Yes.  I haven't filled the transmission with oil yet.  To verify the issue, we removed the slave cylinder from the spacer mounted on the bellhousing, placed a clamp on the slave and lightly pressed the clutch.  Brake fluid came out the back of the slave.

[TexasR400]

Alan - I think you may be correct.  I recall that there is an indention on my spacer, and there doesn't appear to be one on the spacer I see on the Caterham site now.  Never would have noticed that.  I'll take a picture when I get home from work.  I'll also message you with my e-mail address.  I appreciate the help!

- Jake

[Alan Reeves]

 

Ok

 

[TexasR400]

Alan - Here's a picture of my spacer for the clutch slave cylinder.  My spacer seems to have the 1-2mm indentation that you described.  I've ordered a new spacer & clutch slave.  Will give it a try.  Thanks!

https://ibb.co/nkhX9WL

 

[Jonathan Kay]

 

    

Jonathan (posting for a friend)

[TexasR400]

This is the old (bad) spacer right?  Looks just like mine.  The 10mm Duratec spacers on Caterham's site now (part #38Q010B) do not have the groove around the inner diameter.  Hopefully the new part will solve the issue.  For anyone else who runs across this thread in the future - please note that other spacers do have the groove around the inner diameter (for example the R300 spacer meant for the Sadev sequential), however those use a different clutch slave.

I appreciate all of the guidance.

 

[Alan Reeves]

Yes this is my original / bad boy spacer. The car was built as a SV175 which would be the same set up as the R400 apart from your gearbox. As I said perhaps you could just flip this one over to give a flat surface ? Not sure is you have have counter sunk holes but that would be easy enough but perhaps weaken the part as it would be both sides ? But of you have a new part coming thats it sorted. Have you also got a new Slave Unit coming .

Lets hope this sorts you out 

Alan

 

ps. thanks JK for posting the pics for me

re looked and you definitely need counter sunk holes as the Slave bolts over those holes I think 

[Molecular--Bob]

You may also need some thin shims to get the set-up height correct, and if you are buying your new slave locally, make sure it is the Mondeo v6 one as it is the one designed to work with the 10mm spacer. Fitting the shorter 2.0 duratec one can really spoil your day (you can guess why i know this).

[Garth]

Sorry to hear you are having problems. Replaced my clutch slave on my sigma (with Alan!) 18 months ago - had problems getting the spacing correct, but there was no seal at the back of the CSC.

How are you bleeding it? When mated to the engine? Perhaps if it is over extended it will leak from the back? From memory it is almost fully compressed in its 'static' position (ie clutch pedal out!).

Good luck

Garth