Recent Posts

21

A7 & A10 Engine / Re: BSA Goldflash Dynamo Sprocket

« Last post by peter on 20.12. 2024 15:21 »

Hello everyone, thank you very much for all your advice, I did it as Cheeser Breezer suggested and it worked perfectly. Now I still have to look for the right breather cork gasket but it's always the same as it always is  , I have 3mm 5mm 6mm gaskets but it should be a 4mm or 5/32" one.
Thank you again Peter

22

A7 & A10 Engine / Re: Sump plate studs

« Last post by limeyrob on 20.12. 2024 15:02 »

What frustrates me about this is that my current A10 is all rebuilt with a new spring, re-seated ball etc and it wet sumps 1/4 pint a week.  I've had clapped out engines sit for months and smoke for a few minutes on start up.

23

A7 & A10 Engine / Re: Sump plate studs

« Last post by Swarfcut on 20.12. 2024 14:46 »

 If you are talking the anti wet sump valve, strictly speaking it's more of a hold back the tide valve. Sadly on a standard engine this can only be accessed with the crankcases split. Later A65 etc put the valve under the oil pump, so can be serviced in situ. A7/A10 can be adapted, in a similar way, plenty on the Forum.

 Non return valve in the sump is on the return or scavenge side of the pump .Just a simple ball valve, held closed by faith, hope and gravity. In theory this can be removed on S/A crankcases without dismantling, but why this would be needed beats me. Plunger bikes have a different arrangement, pipe has a welded bend, which splits, pump can't scavenge. Engine out, down to bare crankcase to fix.

 Swarfy.

24

A7 & A10 Engine / Re: SRM oil pump

« Last post by Swarfcut on 20.12. 2024 14:34 »

 Make sure the crankcase blind mounting holes are clear and if using the cap screws, check that these to not bottom before clamping down the new pump. While it's off, treat the anti wet sump valve to a good dose of carb cleaner, preferably while the valve is pressed open. Surplus cleaner should be ejected, along with any carbonised oil and other deposits. Purists would remove the PRV and blow through the feed to the timing bush, which exits into the PRV cavity central hole.

 I'd clean out the oil tank while the pump is off, blow through feed and return lines. Finally prime the oil gallery to the timing bush where you've just sprayed, prime the pump, allow it to drain a little before wiping the mating faces clear and assembling with the new gasket. Being an SRM product, all gasket holes should be in the right place and the right size.......

 Swarfy.

25

A7 & A10 Engine / Re: Sump plate studs

« Last post by ringding on 20.12. 2024 14:15 »

A numpty question, is the  non return valve (the ball and spring) only serviceable with the engine out? I'm thinking of my '57 A7 here.

When I changed the sump plate on my Barracuda I had the same issue with studs. I swapped them out for bolts in the end, it was the easiest path for me.

26

A7 & A10 Engine / Re: BSA Goldflash Dynamo Sprocket

« Last post by Swarfcut on 20.12. 2024 14:14 »

   Trying heat with that puller in place is worth a go first.  Without a spare timing gear to hand, another alternative is to remove the inner cover complete, and use a puller to remove the timing gear from the idler shaft. Extract the key, and the shaft will slide through. Now you have just the dynamo pulley on its taper. Only hammer alloy castings (and magneto armatures) if you are rich, to paraphrase a Forum Member.

 Well supported on the bench, ever increasing levels of foul language, threats, violence and heat should ensure removal without damage. Some examples are well defiant.

  Small Cork washer under the drive pulley is more to control end float on the idler shaft rather than a true oil seal. Scroll in the bush keeps the oil out, unless some fool has fitted a spurious part or one from the crankcase location. Bushes are the same size, scrolls are mirror images. Dynamo chain runs in grease, not oil fed from crankcase.

 Swarfy.

27

A7 & A10 Engine / Re: Sump plate studs

« Last post by limeyrob on 20.12. 2024 13:55 »

 
I know that's where this will end up, there's an awful inevitability to it.

28

Lucas, Ignition, Charging, Electrical / Re: Alternator a10s

« Last post by Radlan2 on 20.12. 2024 13:32 »

Hi Nomad.
 I have one, engine No. DA10A 470 with its original GA7 frame. unfortunately it does not have the alternator..., crank, or primary, they were not with it when it came to me.
 It has been my daily rider for about 8years, just taken it off the road for a refresh over this winter. I have always presumed it was an ex police bike, the log book says first registered July '66 and it is on a D plate so I assumed it was registered again after leaving police service.
 I do wish I had the original parts, since owning it I have got hold of an outer alternator primary and I think I could extend the standard crank, it is the inner primary which is the problem, being bigger at the front end. It does have a slightly unusual battery tray.
 Alternator A10 cranks were robbed to make hopped up A65's back in the day.
       So really you are still alone.
                      Chris

29

A7 & A10 Engine / Re: Sump plate studs

« Last post by bikerboy on 20.12. 2024 13:31 »

Dont be lazy Rob cure the wet sumping issue 

30

A7 & A10 Engine / Re: BSA Goldflash Dynamo Sprocket

« Last post by bikerboy on 20.12. 2024 13:25 »

Col

I gave up putting that washer in years ago and have never had oil come thru there, well nothing to mention anyway. I found all that happened is over a period of time that washer fell apart and filled the compartment up with cork