A65 Clutch Alignment

[Wilf2019]

Good evening all,

What is the tolerance of the clutch drum to engine sprocket alignment and best way to check this?

I am just rebuilding my 1969 thunderbolt engine after a needle roller conversion and just checking the alignment to see if the engine sprocket needs adjusting.

I have put a straight edge on the clutch drum teeth and checked against the engine sprocket. However, the measurements never seem to repeat. One check it's flush and then there is a small gap.
Maybe the main shaft has some axial movement? It seems a bit hit and miss.
I have put a clock on the clutch drum and there is very little run out when rotated,  and the clutch plates and pressure plate are fitted.

I have also fitted new clutch friction plates, and when adjusting the clutch centre screw to the correct position the lock nut is only engaged by a couple of threads.
The new clutch friction plates are 4mm thick. Old ones were 3.3mm.
I have checked the rod length and this is 11 1/8". Which seems to be correct to the parts list.

The thrust washer that was originally fitted had the two tabs, is it common practice to fit a plain thrust washer?
If so should this be a good fit on the I/D? The plain one which I was supplied has the same I/D as the washer with the tabs, but slops around on the hub and doesn't locate on anything.

Many thanks for any input.
Wilf.

[DAVE BRADY]

Hi Wilf,

I found this image of the centres which may help.  Slightly different ID as you have said and I do not think that any of them have the little tangs any more as they could wear and break off. The fit of the ID should be snug put not tight.
I have just fitted a new primary chain and it is fiddly.  I think that ideally everything should be torqued up but it is not really practical keep fitting and torquing repeatedly.  I put the front sprocket and rotor on with out the key and just hand tightened the rotor nut.  The clutch basket was assembled on to the centre but without anything else.  The idea of this was that the basket would rotate on the centre and not be influenced by the gear box.  Using a straightedge as you have done I rotate the clutch basket whilst pushing in against the centre.  Any variation can be seen and I suspect that just about every basket will have bit of run out.  I shimmed the front sprocket to get the run out on the basket to about 4 thou.  I am happy with this.  Once the chain is on and everything is tight check again against the chain.   
With the adjuster it sounds like there is an extra plate in there.  The 4mm is the same as some new plates that I have so no problem there.   Is it possible that the ball bearing in the clutch mechanism in the timing cover has dropped out resulting in the pushrod going in further?

Dave.

Dave.

[Wilf2019]

Hi Dave,

Thanks for the reply.
The new thrust washer that I had - had no tabs but seemed way too loose on the hub. In the end I managed to get a replacement thrust washer with the tabs. Which located as the original did on the tabs.
As you say, I've heard that these tabs can come off, but it seemed a better fit than one with no tabs and the I/D too big to locate on anything and just flopping around.
It's in there now so I will see how it goes.

Regarding the clutch adjuster screw, there is the correct number of plates. 6 of each.
However the adjuster screw is wound right in, with the lock nut on 2 or 3 threads.
I've had a look at some old photos and it was like this when I stripped it down.
I think I will look at getting a longer push rod and hardening the ends. I'm still confused why it's like this though. The ball bearing is in the lever end as well.

I have rebuilt the clutch now, and seems to work correctly off the lever, so will have to see how it goes when I finally get round to firing it up.

Regards,
Wilf.