Moss Motors, Ltd

Greetings,

I rebuilt my Master cylinder clutch brakes master cylinder combined. All went well with that it took a summer to get it done but with my Grandson helping me it was well worth the teaching lessons he learned. the slave drive on the clutch was so worn and leaking we decided to tackle that along with all the brakes. (I said summer) well all seemed to be going well untill last night we took it for a drive! The clutch seems to be slipping bad. Well not seems  is. At take off it slips horribly the it catches slowly and then it takes off. Every gear it does this. Iwas wondering if rebulding the master cylinder or the slave is not going back to seat fast enough? Any clues?

You got to love these threads Moss put together.

Randy

Randy,

Unless the pedal actually returns to its rest position sluggishly, it is most likely that the clutch itself is bad. If this is the case, you must remove the engine and transmission as a unit and then separate them to get at the clutch.

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Motorbill
From Lola to Land Rover, If it's British and has wheels, it's likely I've bloodied me knuckles thereupon

I have replaced the clutch pulling the engine only, leaving the transmission in the car.  The advantage is less bulk, weight and length to deal with.  The disadvantage is reinstalling the engine, that is, getting the transmission and engine realigned.  One time it took what seemed like hours of slight adjustments until the engine just slipped right onto the shaft.  Another time I got lucky and got the two units aligned in a matter of minutes.

The reason I always advise pulling both together and doing the disassembly on the floor is the chance of damaging the clutch during the alignment process. It is also a great time to clean out the tunnel and clean off the gearbox, plus replace the gearbox mounts.

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Motorbill
From Lola to Land Rover, If it's British and has wheels, it's likely I've bloodied me knuckles thereupon

Hello Randy,

I have to disagree with bill. I have had the same problem with master cylinders not releasing pressure quickly enough and causing this problem. The clutch pedal can return somewhat to its rest  position even tho the hydraulic plunger assembly has yet to travel to where it should be.If you were to push on the pedal when the clutch is slipping and there is no resistance then the problem is the master cylinder.Certainly if the clutch was fine before then I would be redoing the master cylinder. If you are going to tackle the clutch do yourself a favour and pull the engine by itself. When reinstalling remove the drive shaft remove tranny mounts slide tranny rearward have on hand your $7 alignment tool,line the shaft up using the tool slip the two together.

Gregg

In order for a master cylinder to not release pressure fast enough it would have to be clogged with something much thicker than hydraulic fluid, or have the pushrod overadjusted (on these dual types with adjustable pushrods) or have some other SEVERE malfunction. The fact is that the pressure exerted by a healthy clutch is considerable. Sure, if the clutch is slipping and there is absolutely no resistance in the pedal there might be something hanging it up mechanically, but I took the gentleman at his word when he said that he had freshly rebuilt it.

In my forty years in this business, the overwhelming results of investigating a slipping clutch have been that the clutch is worn out or broken. I will repeat my advice to remove both components as a unit. Shortcuts usually end up long. You do not save enough time removing only the engine to make it worth the inconvenient working conditions, or the loss of opportunity to service the items you can reach when both items are removed. Everyone, obviously, has their own style and is free to do as they please with their own property. I was asked for the benefit of my experience and I gave it. 

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Motorbill
From Lola to Land Rover, If it's British and has wheels, it's likely I've bloodied me knuckles thereupon