GEARBOX OVERHAUL WOES

[mike3md]

I think Willie has to confirm what sort of clutch he has - original (up to TR4) coil spring type, or later (TR4A on) diaphragm spring type. They do not use the same type of release bearing.

 

The face of the earlier release bearing is flat.See wsm p 2.101 (TR4) and p 2.109 (TR4A)

 

Mike

[Willie]

Clutch is original type, NOT a diaphragm unit.

 

I am about to complete the overhaul with a mate and need confirmation in the next 2 hours!

 

Best wishes Willie

[Steve Priest]

Hi Willie,

 

I'm certainly no authority but I installed my TR4 spring clutch release bearing the same way as you - flat side outwards towards the clutch. It's been happily working for the last 4 years. The old bearing I removed was installed the same way.

 

Steve

[Willie]

Thanks Steve! That ref to the bearing working happily is good confirmation.

 

Best wishes Willie

[Willie]

Car back on the road with all working!! Once again a huge THANK YOU to everyone who has been so helpful in reaching a successful outcome.

 

Best wishes Willie

[tim hunt]

I just picked up on this thread and am glad you had a satisfactory result Willie. Mike's post #26 prompted me to have look at the illustrations of the TR4 and 4A clutch assemblies in my WSM. I was intrigued to see that adjustment of the TR4 clutch is stated to be by the slave cylinder push rod whereas the TR4A clutch is apparently NON-ADJUSTABLE. I have an adjustable push rod on my slave cylinder and one is shown in figure 17 on page 20 of my original owners handbook. Strange. Incidentally, while the TR5 and 6 hav e the same diaphragm clutch as the 4A both later models do have non-adjustable slave cylinder push rods. Why is this?

 

Tim

[Andy Moltu]

The adjustable push rods work in conjunction with a pull-off spring so that the spring doesn't pull the push rod too far back so that when you press the pedal there is no large clearance to take up before the release bearing contacts the fingers of the clutch..

 

The 5 and 6 don't have a pull off spring so the release bearing remains almost continuously just in contact with the clutch fingers.

[Willie]

Hi Tim,

One additional item of relevance is that, although the clutch was working perfectly pre gbx overhaul, when all the new bits were reassembled, we couldn't select gears with the engine running. You will see in earlier postings that this was flagged up. In the end we fitted a complete new hydraulics - master & slave cylinders, and slave pushrod. Outcome.....all good! Strange that we had to do this. Clutch plate and housing were probably OK for reuse, but it was only the release brg and sleeve which were worn. The inner face of the brg was actually a "drop-on" fit to the sleeve, yet there was no obvious problem with the clutch. Methinks my call to do the overhaul now probably save a roadside recovery job! Best part of £2k spent, but looking forward to anxiety-free motoring now!

 

Best wishes Willie

[tim hunt]

This business of the return spring has always been a grey area for me Andy. Granted, the Moss catalogue clutch hydraulics illustration doesn't differentiate between the 4 and 4A and shows a return spring. However, none was fitted to our 4A on acquisition in 1970 and none is shown in figure 17 of the 4A owners manual.

 

Tim

[Andy Moltu]

Without a return spring the need to adjust the push rod is essentially redundant as the hydraulics essentially self adjust.