W124 clutch master cylinder specifications?

hismajestics

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Are there many different sizes of W124 clutch masters? I know that the older Mercs eg. W114, has a 19,05mm caliber cylinder. And I am of the understanding that the size is the same in W124.

The problem is that I'm having difficulties in getting the clutch work properly in my W114/M104 swap using original master from W114 and original slave on W124 5 speed ZF manual gearbox.

It's a long travel on the pedal, almost hitting the floor, before the clutch will engage. This tells me that the caliber/piston in the original W114 clutch master is of inferior capacity in regards the W124 slave.

Or can it be something else?

/johannes
 

carat 3.6

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As far as I know the w124 and w201 all use the same master and slave cylinders, the slave cylinder is also shared with the w123 and w114 so I would expect the master to be the same too.

Does it have much free travel on the pedal? Also some gearbox'es have a plastic shim between the slave cylinder and the bellhousing, try removing that.
 
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hismajestics

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As far as I know the w124 and w201 all use the same master and slave cylinders, the slave cylinder is also shared with the w123 and w114 so I would expect the master to be the same too.

Does it have much free travel on the pedal? Also some gearbox'es have a plastic shim between the slave cylinder and the bellhousing, try removing that.
Thanks for the advice, carat.

It's free travel almost to the floor. It engages some 20-30mm before.

It's strange since the specs should be the same as they were in W124. I drove the car before the swap and there was no issues with the clutch.

I'll check the shim.

/johannes
 
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hismajestics

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Did you drive both cars or just one?
Sorry, a bit unclear...

Yes, I drove the donor E320 before pulling the engine and gearbox off. No issues with the clutch.

I've also been driven the W114 with the E320 engine and driveline. Here I face the problems with the clutch.

/johannes
 

John Jones Jr

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O.k., what I was trying to establish was the W114 master cylinder o.k. before you fitted the M104 engine & box?
If Carat 3.6 is correct about sizing, no reason to doubt him, then problem would point to a faulty W114 M/cylinder.
Now, I know from experience disconnecting either or both cylinders and then reconnecting and finding it impossible to get a pedal was due to a worn cylinder and only showed up after a lot pumping, trying to pull fluid.
I'd suggest you rebuild the Master cylinder presuming it is the correct size for the Slave cylinder.


P.s. great project by the way. the W114 should fly. maybe some photos in due course?
 
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hismajestics

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JJ: very good point! The clutch in W114 worked great before the swap. I'll take a sharp look at the Master cylinder.

Pics will come when I get the car out of the garage again :thumb:

grober: I'll double check the hose.

Thanks!

/johannes
 

Druk

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Did you get the clutch fixed Johannes?

My conversion uses a 320 flywheel and clutch so I used a W124 master cyl mated to the 107 pedal box. The bolt centers are only slightly out but the spacing off the frame is different and I made a conversion bracket. Also iirc I used the cyl pushrod from the early cly and grafted that into the one from the 124. It all works fine. Instead of the rigid metal/rubber pipe I used clear 8mm nylon diesel line which also works well and saves a lot of routing bother.
 
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hismajestics

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Did you get the clutch fixed Johannes?

My conversion uses a 320 flywheel and clutch so I used a W124 master cyl mated to the 107 pedal box. The bolt centers are only slightly out but the spacing off the frame is different and I made a conversion bracket. Also iirc I used the cyl pushrod from the early cly and grafted that into the one from the 124. It all works fine. Instead of the rigid metal/rubber pipe I used clear 8mm nylon diesel line which also works well and saves a lot of routing bother.
Derek, I'm getting used to it
icon7.gif
. After all, it works, not perfectly but anyways...

Btw, are you saying that W124 master cyl has a bigger diameter piston than W107 or W114?? I thought they were both 19,05mm :confused: Or, is there something i've missed?

You don't happen to have some pics about the conversion you are describing. Not being as handy as you but could give it a try with some proper guidance ;)
 

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