[chris hedley]

Hi , Has anyone had problems when fitting the new style clutch as opposed to the original three finger type plate ?

I am pulling what hair I have left, out !, I just can not get hydraulic pressure ,I have bled the system time and time again , I was wondering if it needs longer push rods or something I have not thought about .
Thanks Chris

 

[franco-veloce]

Hi All,

I used a diafragma style clutch from BMW 323/325 ( years 1980) same as used in 2300 rio
in my 1900CSS and 2000 touring
I changed the length of the collar ( bearing holder ) , because the original old sachs three finger type has other dimensions.

rgds Franco

 

[DPeterson3]

Chris,

May be relevant, may not.

My FNM2300 came with a diaphragm style clutch. When I redid the engine I matched the pressure plate to a BMW unit and it is operating still.

The throw-out bearings are different for the old three finger, as is the length of the collar the bearing fits on. However, I have to believe that the kits being sold now are not the same as the one in my 2300. The bolt-holes and dowl pins are not at all the same. I went to the lengths of having my FNM flywheel drilled so it would accept either style plate, but expect the BMW unit to be available for longer than I'll be alive.

However...

The original three-finger plate requires a return spring and adjustment to establish a small degree of free play. The diaphragm style plates that have the throwout bearing pressing down directly on the diaphragm fingers do NOT use a return spring. The throwout bearing is intended to always rest on the fingers and spin with the plate. So - if your new style pressure plate has a COLLAR permanently fixed to the many fingers of the pressure plate, then you will continue to use the return spring. if there is no collar on the pressure plate, you need to remove the return spring.

In the latter case, the slave cylinder will extend naturally and stay extended, as there is no spring to drive it back into the body of the slave cylinder. If you have the return spring, it will always retract as far as it can.

As for using a longer shaft AND a return spring... Probably a bad idea.

Decades ago I saw what happens when one uses a return spring on a diaphragm, no-collar pressure plate. Every time the clutch is pressed, the pressure plate has to "spin up" the throw out bearing, during which there is relative motion between them. This transfers a lot of heat to the thin fingers of the pressure plate, leading to them getting soft and folding inward, sort of ruining everything.

Without a spring, the T/O bearing will be in very light contact with the thin fingers of the diaphragm itself. Not enough to cause premature wear in the TO bearing, but enough to keep it up to speed.

 

[chris hedley]

Hi Don, thanks for the reply, what you say makes sense, it's along the lines of what Franco said, I would still like to find someone who has done one on a 2600, I may be nieve but I'd like to think that suppliers would add a warning note to the kits when it's sold, as far as I remember the thrust (throw out) bearing was the same as the replacement one, I may be wrong, I will have to look further into it, I the mean time, anyone that has changed over, can shed some light on it. Thanks Chris

 

[DPeterson3]

Does your new pressure plate have exposed fingers of the diaphragm to bear on, or does it have some sort of device in the middle which the TO bearing will push on, instead of the diaphragm fingers?

I ask, because if it has a collar, as many diaphragm pressure plates due, that may resolve the need for a longer collar holding the TO bearing, and may also allow you to use a return spring as original.

Picture of the pressure plate?

 

[DPeterson3]

The pictures show the collar mounted into the diaphragm spring, so you should be able to use the original TO "spacer-collar", and a return spring without doing any harm. That would relieve the selling distributor of needing to add any installation notes.

Might be a master cylinder that isn't adjusted correctly, or too much air in the line, or the slave shaft hasn't been correctly adjusted. If you need a new, longer shaft, I'd say the vendor owes you an explanation.

Master cylinder should have a return spring as well, and it should have the same small free-play with the push-rod-to-pedal as with the brake master cylinder.

 

[riggs]

Hi Chris. I have the new style clutch fitted to my 2600, bought from classic Alfa. My friend Dave fitted it whilst I was at work, as far as I know it was a straight fit and forget. Where did you buy the kit from?

 

[chris hedley]

Hi Chris. I have the new style clutch fitted to my 2600, bought from classic Alfa. My friend Dave fitted it whilst I was at work, as far as I know it was a straight fit and forget. Where did you buy the kit from?

Hi

Hi Chris. I have the new style clutch fitted to my 2600, bought from classic Alfa. My friend Dave fitted it whilst I was at work, as far as I know it was a straight fit and forget. Where did you buy the kit from?

Hi Brian, I got it from Classic Alfa, I only changed it because of what I thought was a thrust bearing noise, it ran OK but pedal was very erratic sometimes OK other time I had to pump it up, and it still had the bearing noise, as usual when you floor the pedal the noise stopped, Classic Alfa sent another bearing, but again the noise was there, to try and sort the pressure problem I changed master and slave cylinders, but no matter how many times we bleed it, it still goes to the floor. My next job is to fit a longer master cylinder rod, the next step if that doesn't work I'm going to drive it into a wall, ( if the clutch works!!)

 

[riggs]

I have the bearing noise only noticable at idle, slight touch of the clutch pedal stops it. As for Master and slave rods, I only had one for the slave. I used the original rod for the slave with a longer fork, and I used a coach bolt which I cut to the length I needed for the master. I've not had any issues with mine other than the noisy bearing.
Driving it into a wall is an option and one I have considered many times 😄

 

[chris hedley]

😂 I know how hard can it be, a simple hydraulic system, I will not be beaten, I'm a bit frantic at the moment, with other jobs on the go, my mustang needs a propshaft, my xk150 is sounding like a distressed whale when reversing, ( brakes) and I'm still struggling with the quarterlight rubbers on my sprint gt. But life goes on. Thanks for the reply. Chris