Weird clutch

[Worty]

Worty, I had the same issue with the engine sprocket away from the engine by 3mm for my 1961 A10. My new cush sleeve bearing (42-0069) had a shoulder thickness of 8mm, so I machined 3mm off it for a final thickness of 5mm. Draganfly has three Part numbers for the S/A cush sleeve bearing (attached). My new 21 tooth sprocket has a shoulder thickness of 1.87mm, so I left that alone and just took metal from the sleeve bearing flange. The spacer which Berger put on the correct way round is 10mm thick if I remember rightly.
John Chaterlea's excellent article below covers this issue and the clutch centre issue very nicely.
                  https://www.a7a10.net/forum/index.php?topic=9646.msg70166#msg70166
Col

I think Col's issue is my issue.  There is no shoulder on the sprocket, but the shoulder on the cush sleeve is indeed 8mm.  With a cursory measurement, I reckon 3mm would do it, especially as super accuracy is offset by chainwheel wobble.  I reckon that 3mm off the cush sleeve shoulder is the way to go - Bergs, do you concur?

[Worty]

Just one other thing re the cush drive nut.  Is there any big problem with creating a big, thick circular plate (a big washer, if you like), and belting that up on the cush with a suitable nut?  It would seem that SRM's item is a bit like that only the 'plate' and 'nut' are one piece.  I will need to replace my cush nut as the original is knackered.  I would have bought the tool off Ebay, but this'd be the same price as the SRM item once a new, original nut had been purchased as well.

[JulianS]

I dont think that is a good idea, not enough threads for a nut.

Below photos show an SRM nut first with the nut done up second showing the threads .

[Swarfcut]

  Machining material from the face of the spacer next to the crank (or even a new custom spacer) may be an easier option and preserves the existing drive sleeve. Moving everything closer to the crankcase brings the chain closer to the primary inner case....if there is no circular plate, then this a problem. Removing the plate or even making a thinner version solves that conundrum, then we have the fixing at the lower rear of the chaincase to the frame, which must be arranged so no strain is placed on the chaincase. Hooligans solution is a stack of washers.

 As for the big nut, something that fits, special tool, homespun peg spanner from tube or something fabricated from scraps. Hammer and punch is a sure way to wreck it. The more about this engine we learn, the more mix'n match parts there seem to be.

 What model is it?  It's a '54, '55, 56, 57, '58 '58.....'59  We all know how that ended up.

 Swarfy.

[JulianS]

A Citroen/Peugot 405 lower ball joint socket fits the original cush drive nut. Takes a 35mm socket to drive it.

It is a tight fit and if the nut has been bashed with a hammer it wont fit.

Lowest Ebay price in UK is at the moment £11.45 post free.

The same tool is being sold as a BSA crank nut tool on ebay for £21.99 plus £3.50 post.

Photo is the one in my tool kit shown with a new old stock nut.

[berger]

worty i have an original nut how have you knackered the one that was on it?

[muskrat]

G'day Worty.
Google found this one https://www.tradecounterdirect.com/sealey-sx027-lower-ball-joint-socket-peugeot-405-citroen.html
and DF for the nut https://draganfly.co.uk/shop/74520/engine-shock-absorber-nut-dished/#67-1137
Cheers

[berger]

worty make sure the cush nut isn't going to bottom out before it has tightened up on the sprocket sleeve to the bearing collar if it needs 3mm off it, there are loads of different cush sprocket carrier sleeves, i found out the hard way in the 80's when building mine up after the snapped crank episode. snapped crank pic just to cheer everyone up.

[Worty]

Thanks fellas, much appreciated!

Swarfy - it's a '61 Flash.  Not too concerned about the proximity of the chain to the inner primary, seems to be plenty of room even with the plate (which is present).  The rear fixing of the inner primary to frame is pretty good (only one washer ), but I like Col's suggestion of putting the primary cover on first and tightening everything up before securing the rear fixing.  This would seem to take any strain/flex off the inner primary allowing the two surfaces to mate better.  Also, is there any sense in putting two gaskets on, seem to have an issue with primary leaks?

Julian - thanks, I'll look into that one.

Bergs - the nut wasn't great anyway.  I've not really damaged it too much but I think it's time for a replacement anyway.  Not sure how the cush nut would bottom out mate, doesn't it just screw up until it hits the collar sleeve? 

Col - did you have any issues with bottoming out?

Musky - cheers mate, will check them out - would be nice to keep it as original as possible.

Anyone want to comment on how RM missed this alignment issue - being a specialist in classic rebuilts, of course??

[Worty]

Just thought Bergs, if you take the 3mm off the inner part of the flange/shoulder rather than the outer, it preserves the overall length of the collar anyway - the nut should then screw up as before?  If there was any issue with, say, spring tension on the cush, is it possible to shim up somewhere.

[berger]

worty offer up the sleeve to the bearing collar and see how far it sticks out over the threads then you can choose which bit gets turned off.  don't forget these bits are hardened and you will lose it on whatever bit it taken off, but it shouldn't present a big problem.

[Worty]

worty offer up the sleeve to the bearing collar and see how far it sticks out over the threads then you can choose which bit gets turned off.  don't forget these bits are hardened and you will lose it on whatever bit it taken off, but it shouldn't present a big problem.

Cheers Bergs.  It'd make sense to me to preserve the length of the collar as it fitted fine when you put it back together.  I have now ordered the Peugeot/Citroen tool for £11.45 and a new cush nut for £13.99 (both free postage).  Would you and MWAS be happy to do the skimming at his and yours convenience?

[berger]

worty yes this is what i mean by offering it up, this one for the berglar build has a 5mm shoulder . give me ring and we can sort something.

[Worty]

worty yes this is what i mean by offering it up, this one for the berglar build has a 5mm shoulder . give me ring and we can sort something.

Giz a sec' mate, I'll finish the egg on toast and nip t' garage to check it out.

[berger]

egg on toast love it