Clutch Failure

[willincalgary]

Driving home to pick up my kids tonight I was thinking to myself that the Rover was driving really well lately. Of course this thought cursed me (or more correctly the truck) which then promptly up and failed. Pulling into a parking lot I attempted to double clutch down into 2nd gear and the clutch would not disengage the gearbox.

I've had a clutch fail in the past but it was very progressive, it just got more and more difficult to get the clutch to disengage. This time the clutch failed within a block, from perfect to not functioning.

When I depress the clutch pedal it moves about 1/4 to 1/3 of the usual travel and stops abruptly. No amount of force will cause the pedal to move further. From underneath you can see the end of the slave's push rod move and then promptly stop as well.

Any thoughts as to what might have gone wrong? I'm thinking I should detach the slave push rod from the operating lever and see whether the master/slave combo operates through its entire range. If so the problem must be internal to the clutch.

[willincalgary]

Update

Disconnected the operating lever from the slave push rod this morning and verified the hydraulic part of the system is working. I'll bump it into my garage now, take out the floor and let you know what I find in the cross shaft fixings. The green bible doesn't have a good diagram showing how the cross shaft operates the clutch. I assume it actuates the release levers some how but I've never had this apart so don't know for sure.
I'll advise what I find.

[NC_Mule]

Keep me posted, I'm on that progressive clutch failure that you describe and I don't know much about the cross shaft. Take a few pics if you have a camera handy.
Good luck, pb

[willincalgary]

Took out the floor to get a good look at the whole works. Found that all the pins connecting the cross shaft (the ones that go through the cross shaft connecting tube and the cross shafts) were sheared. Normally I'd wonder about what caused the pins to shear except that the connecting tube is, I believe, a bodge job somebody did sometime in the past 55 years (see picture). The tube's inner diameter is larger than the outer diameter of the cross shaft and it has been crimped closed in a vice. This lead to more play in the whole mechanism and that play probably loaded and stressed the pins in ways they were not designed to be stressed/loaded. The sheared surfaces of the pins look very fresh so it may be that yesterday one or both of the pins sheared essentially disconnecting the operating lever from the cross shaft..... no clutch! The fact that one of the pins sheared or broke in it's middle supports the awkward loading argument I think (not simply sheared at the interface of the tube and the cross shaft). Seven years I've owned this truck and I still find things that need to be put right.

Now I'll find parts and see whether that was all that went wrong.

[willincalgary]

In conversation with a parts supplier I've been told this is actually how they were designed. Interestingly this is not how it is shown in the Repair Operations Manual for the Series II/IIA. Apparently the design would allow for a slight misalignment of the two shafts as it would act like a miniature u-joint. Seems crazy as the inevitable result would be clevis pin failure. I guess they had some method to the madness!

[I Leak Oil]

You may want to look at the spherical bushings in that shaft assembly as well. If those are worn it will exacerbate any misalignment putting more stress on that coupling and the pins.

[stomper]

I went through an issue like this with a friend's rover this fall. his pin sheered off, but was frozen in the shaft, and was impossible to remove with the angles and positioning without removing the whole transmission. Like you mentioned, his was also elongated, and looked like someone had placed it in a vice like a bodge job.

The pins should be a hardened steel, so a few new pins, possibly a new coupling if the pin holes look worn, and it should be back on the road. It is definitely worth checking the bushings while you are in there, like leaky mentioned, but I'm betting you are just dealing with some metal fatigued parts that finally let go.