Hydraulic clutch

[shaun]

Does anyone know the thread used in fiat x1/9 clutch cylinder and montecarlo slave cylinders, presumably 1/4 in pipe will be ok?

[stableblock]

1/4 inside diameter ? That what I have used on long clutch lines before without any problems.

Peter

[chris.richard]

Can someone post the travel of the clutch master cylinder? I'm using an X19 mastercylinderand an Alfa 164 slave, but I don't think the clutch is disengaging properly.

[shaun]

My piston travel is not less than 30mm possibly as much as 35 on the x1/9 cylinder. Still trying to get hold of some unions to connect this to the slave and check it works.

[rutthenut]

I found that there was some unused travel at the slave cylinder for the clutch, so made up a longer pushrod and fitted that in place of the standard piece. From memory, I probably made it about 20mm longer. If it is too long though, it won't fully disengage and you would end up 'riding the clutch' and possibly wearing the release bearing and/or clutch fingers.

That is with X19 master and 164 slave cylinders, and without the damper reservoir fitted to the standard Alfa - what's that all about?

[Sando]

Can someone post the travel of the clutch master cylinder? I'm using an X19 mastercylinderand an Alfa 164 slave, but I don't think the clutch is disengaging properly.

Chris check out the newsletter CD and the very early issues, there were a couple of good bits about the travel at both ends and some tips to get a bit more.......like altering the throw of the lever at the M/C end and flattening the bottom of the clutch pedal tube so that it can be pressed a little further.......all to get more movement at the slave end to get more movement and stop any drag :) This was for Beta engines at the time, but I'm sure applies to the V6 too.

Cheers
Rob :cool:

[shaun]

I welded a small arm on top of the pedal shaft and found that the limiting factor was the gap between front bulkhead and the square section that the coloum is bolted to. Surely an engineer amongst us can calculate the theoretical values as from memory the master cylinder has potentially more travel than 30mm.

As for the internal outlet thread, M12?

[chris.richard]

My clutch is of the "pull" type release bearings. I don't know if that makes a difference.

[chris.richard]

As for the internal outlet thread, M12?

From my Demon Thieves order:-

STRAIGHT MALE CONVEX SEAT M12 x 1.0 SIMILAR TO 445-31P 1

STRAIGHT MALE CONVEX SEAT M12 x 1.25 SIMILAR TO 445-31P 1

GOODRIDGE 600 HOSE 600-04 3 metres

Don't know which thread was which end of the clutch hose though! 3m of hose is a bit tight on length - another half metre would have been better. :rolleyes:

[shaun]

And the trouble continues........

Has anyone used a 164 clutch master cylinder and a 164 slave?

Since it was impossible to get some M12,125 unions my X1/9 and montecarlo bits have been changed to Fiat croma TD parts, the same as 164(I hope).

I have about 30mm travel at the MC and 11mm at the slave. Checking a std beta 21mm displacement is required at the slave.

I did of course not measure either the Fiat cylinders just assuming that the bore dia. ratios would be about the same. I'm off to kick myself.

[strat6v]

Shaun, I have some x19 m/cyl unions somewhere, do you need one?

[chris.richard]

Coincidentally, Roger Donnan phoned me with his clutch setup travels today. He's got the X19 M/C and the Alfa slave. His M/C travel is 30mm and the slave travel is 15mm, and his clutch works fine. My Alfa slave travel is also 15mm, so my clutch I hope, just needs used to loosen it up a bit.
Which engine/gearbox are you using Shaun?, I've forgotten.
Think Automotive will be able to come up with the connectors you need.

[shaun]

Engine is beta volumex, gearbox probably volumex as well

I would be very interested to get hold of some unions for 1/4" copper pipe, from memory they are male M12 by 125.

I managed to measure the cylinders, the Fiat Croma MC was 22mm and the Fiat Croma slave 25mm - the other way round and things would have been better. The X1/9 MC and montecarlo slave are both 19mm.

Options include shortening the clutch operating arm, getting some of those impossible unions or a scrapyard visit. That reminds me the slave was off a 24v 164 engine not the croma.

Who can explain the maths involved, piston travel/bore/force/temp change?

I'll make a start:

(3.15*((22/2)²)*30)*F1=(3.15*((22/2)²)*11)*F2

and leave it at that as the priority is finish bodywork ready for some paint.

[rutthenut]

For the Alfa 164 transmission, don't forget that there are two slightly different installation styles, for 12v and 24v clutches. The 12v clutch lever arm 'pushes' onto the clutch fingers, whereas the 24v style 'pulls' the clutch centre.
I don't think there are any differences between the actual slave cylinders, but could easily be wrong about that.

Another point - Roger Donnan has mounted his X1/9 slave cylinder differently to the 'standard' Hawk mounting, since he put his on as a conversion to the HF2000 before Gerry had come up with the solution on the HF3000 kit.
This *could* mean that he has more travel at the master cylinder pushrod than on the HF3000, but the chances are that both use the full available travel in the master.

A further point that I, and others, have done is to lengthen the slave cylinder pushrod. This is the simple rod that comes out of the slave and presses against the clutch lever arm. There is a fair amount of wasted travel here, so substituting a longer pushrod (cut down coach bolt, with tapered/turned ends) can ensure that all travel at the pedal is translated to movement on the clutch. Just don't make it so long that the release bearing is in constant contact with the clutch fingers.

Sorry, don't have the figure any more for how much I lengthened it.

If we work out that figure, it would probably be worthwhile passing the info back to Gerry so he might include a replacement pushrod in future HF3000 kits.

If using a different pedal box, such as a Tilton, I expect the master to pump more fluid than the simple X1/9 unit, so this modification may not then be needed.

Enough comments on that from my fading memory.
Off to watch Roger at Brands Hatch again today...

[Chris J]

I welded a small arm on top of the pedal shaft and found that the limiting factor was the gap between front bulkhead and the square section that the coloum is bolted to. Surely an engineer amongst us can calculate the theoretical values as from memory the master cylinder has potentially more travel than 30mm.

As for the internal outlet thread, M12?


Shaun

Do you have the Hawk/Transformer front bulkhead modification? It stuck me that I didn't see one in the progress photos of your car.

It's a fibreglass cover that makes space and tidies up the hole that needs to be cut in the front bulkhead near the top of the clutch pedal.

I found out about this bulkhead mod./cover, far too late (with my first car). I kept grinding bits off the clutch pedal as I tried to make it clear the (non modified) bulkhead. If only I'd known then what I know now.

[shaun]

"If only I'd known then what I know now", how many times have I said that to myself. The second car will be perfect.

Anyway, no bulkhead bulge as yet!

I welded in a box section with a plate to mount the x1/9 mc. Pedal pivot travel was at least 30mm. This has just been replaced with a sort of L shaped bolt on mounting for the Fiat/alfa mc. The slave mounting is still a prototype as can be seen from the two M8 studs.

I think the next stage is to get an aeroquip cable made up to use the montecarlo slave cylinder but, I hope the 3mm extra diameter of the fiat mc will not give a heavy pedal or pop the slave piston out.

[Chris J]

Shaun

It's all clear to me now. Pictures tell a thousand words.

It's just that when using the standard hawk clutch master cylinder bracket there's no way round cutting a hole in the front bulkhead.

I just wanted to make sure you didn't make the same mistake as I did.

I remember having to tap a couple of blank holes on top of the gearbox for the slave mounting because of the Beta box having been a cable type.

[chris.richard]

Finally got my clutch working properly! Yippee :)
When I'd made up my home-made mastercylinder mounting (I didn't realise Gerry had already supplied one under the dashboard! Doh!) I made a mistake in the length of the lever attached to the pedal, with the result that I had insufficient travel in the m/c. :rolleyes: I've now extended the lever slightly, re-angled the m/c to compensate, and successfully driven up the road to put the car in the garage the other way round. Result!

[strat6v]

Did you remove the g clamp :p