What's inside this ?

[Aristotle]

Lying on my back under my Spitfire gazing up at the underside of my new diff (thank you Mike Papworth) I felt the need to go rocking the propshaft back and forth.

There's a bit of a clunk me-thought.

It seems to emanate from that can shaped thing at the diff end of the shaft.

Whilst there's a UJ at the gearbox end of the shaft and that seems fine, what ever is inside the can, presumably something that allows movement, should it have play in it ?

Gripping the can with one hand and the shaft with the other there is play between the two.

The can (as I call it) is open at the forward end for the shaft to enter through what appears to be a rubber bellows/large grommet, before it engages with what ever gubbins is inside.

Asking for the wisdom of those that know - what's inside and should it have play ?

Car's a 78 1500 with overdrive.

 

[Josef]

It’s a sliding joint to allow for slight movement of the diff relative to the prop. Well, or some equivalent, I’m only familiar with earlier cars and their joints look different. Back to front play sounds like normal movement, side to side might be an issue, but depends on the design of the joint so I’m not completely sure there.

[johny]

Yes its to do two jobs, permit axial movement as the distance between gearbox and diff changes plus angular movement as they go up and down relative to each other. Before this was done with a sliding joint plus separate UJ and Ive not seen inside one of these later design jobbies but I imagine its like a CV joint on FWD car drive shafts. There shouldnt be any play but if your not noticing any vibration or clonking in transmission take up then its not an immediate worry...   

Edited May 24 by johny
another mistake

[chrishawley]

Ditto as per above. I've got one of those on my Spit 1500. Perhaps best known to classic Mini owners as the 'Pot Joint' on the front driveshafts. A CV joint in effect. Not servicable or replaceable (where Triumphs  are concerned) and, yes, both plunge and angular movement are (of course) a part of normal operation.

 

[Josef]

Ahhh, I didn’t spot there was no UJ!

[johny]

I think the trouble with our cars is that theres very little movement for the propshafts (angular or axial) so all the torque is always taken in exactly the same spot resulting in localised wear while the rest of the component is fine! I almost wonder if it wouldnt be worth making up a spacer to go between the flanges so that the prop runs a little bit shorter...

[Colin Lindsay]

TR7s use them too, in time the rubber splits and allows water into the joint so keep an eye on it. Pumping grease into any split or tear as a short-term 'help' will give a few more miles.

[Aristotle]

Interesting responses chaps - many thanks.

Aaah so it's like a CV joint - it can move up/down and in/out - that explains it.

Thing I'm not clear on is - should it have any play in it rotationally (if there's such a word) i.e. holding the outside of the can (CV Joint) still whilst rotating the prop.

There is a definate clunk with a distinct gap before the can takes up against the rotation of the prop.

Is this normal ?  

 

[johny]

No there should be no rotational play. Those balls you see in the pic fit snuggly into the channels in the cup so can slide in and out and to different angles but as they always sit in the same position they wear pockets in the channels so are no longer snuggly! Can you feel anything when driving? If not drive more😁

[Colin Lindsay]

1 hour ago, johny said:

No there should be no rotational play. Those balls you see in the pic fit snuggly into the channels in the cup so can slide in and out and to different angles but as they always sit in the same position they wear pockets in the channels so are no longer snuggly! Can you feel anything when driving? If not drive more😁

After long periods of driving I usually can't feel anything at all, and have no idea of where the balls are at. 

You could always replace the propshaft with an earlier type; I'm not sure if the length is the same but even there you could have any kind shortened and balanced. That CV type has been debated by the TR7 fraternity as unrepairable or unserviceable, so the earlier and hopefully simpler type might be easier to maintain.

[johny]

All depends if its causing a problem...

[Aristotle]

It's interesting because I've been chasing down and gradually eradicating various noises in the drive train.

These noises occuring at different speeds loads and I'm now down to a clunk.

Started by checking the wheel bearings now OK after finding one a bit loose.

Moved onto replacing the UJ's in the drive shafts, before having the diff refurb'd.

At each stage things improved so I'm happy they're done.

The clunk is at drive take up particularly in changing direction, I can induce it by moving forward then backwards - clunk then quiet.

Since learning where it's likely to be coming from, I see new prop shafts are available with a greasable sliding joint and UJ both ends, balanced and ready to go on the car.

Seem reasonably priced for new - - https://rimmerbros.com/Item--i-PKC1467   

Anyone got experience with these ?

 

 

[johny]

With the wheel bearings the front should have some play and it is a problem with many mot testers failing them which is totally wrong.

There will always be some slack in the drive train its when it becomes noticeable changing from power to trailing throttle that action is necessary...

[Dick Twitchen]

Personal preference but I have been more content with my dealings with James Paddock https://www.jamespaddock.co.uk/propshaft-od-1500-2

Dick

[Pete Lewis]

with  any clunk  dont discount simpler things, loose wheel nuts  .tie rod bushes,  hub nuts and keyway

diffs dont clunk   planet gear can .

Pete

[68vitesse]

Had a clunky when going forward then reverse or vice versa on my Vitesse, turns out to be a loose rear brake backplate. The bolts had been fitted with lock washers instead of the proper lock straps.

Regards

Paul.

[Pete Lewis]

and another to add  is poor rear brake adjustment including often the trailing shoe s upside down

so there becomes a lot of shoe /cyl  shift on reversing etc

all the little things add up to a clunk 

Pete

[Aristotle]

On 26/05/2024 at 18:22, Dick Twitchen said:

Personal preference but I have been more content with my dealings with James Paddock https://www.jamespaddock.co.uk/propshaft-od-1500-2

Dick

Dick, thank you for the suggestion, unfortunately only caught up with your comment this morning and the one from Rimmers is arrivimg today.

See that the one from Paddock is also £30 cheaper - so will consider for bits in the  future.

[Steve P]

Too late now but I would always recommend Bailey Morris for anything prop related, they made me a bespoke one for my 2.5 Vitesse with a smaller diameter tube and bigger flanges and U/J`s at a very reasonable cost.

I think they are not far from You in East Anglia ( and Feltham ).

Steve

[Aristotle]

Septuangenarian reporting back chaps, after much grunting and groaning to get old prop (and exhaust) off and new prop and old exhaust back on.

I now have  - - - - no clunk !

Confirms it was the CV joint on the old propshaft, now it's off the car, play can be felt more clearly in the joint.

Not really much of a job to do, apart from front joint which takes a little patience as access to nuts and bolts restricted.

My only other comment would be - the new nyloc nuts purchased to replace the old ones had shorter shoulders than the old ones and consequently in restricted places the spanner can slip off. 

In fairness, if you get the spanner on straight you can get them tight enough but the old ones with taller shoulders just made the job much easier.

So question for next time - - is there a supplier out there where you can buy old spec nut's ?

 

[trigolf]

Try Namrick in Hove for UNF nuts/bolts.

[chrishawley]

11 hours ago, Aristotle said:

the new nyloc nuts...

Nyloc full nuts come as either 'P' (tall) or 'T' (thin). In general 'P' is about 20% thicker than 'T', for a given thread diameter. In situations where it matters one needs to specify P or T when ordering but some general sellers seem oblivious to the distiction. Try Namrick as they are most helpful with details such as this.

Does a thicker 'P' have better 'fixingness' than a 'T'? I have no idea!