Help! Why does my nut keep coming off?!

[nimrod650]

I don't suppose there's any sort of tool (apart from a C Spanner) out there that makes it easier to tighten the nut is there?

Confession is good for you: I'll come clean and admit that I use a pipe wrench, (Stilson) to tighten mine.

an old primary chain and a piece of pipe thread ends of chain down the pipe to form a loop at the end of the pipe  place loop round the nut and lever away works for me use it to remove old oil filter on car as well

[RichardL]

 an old primary chain and a piece of pipe thread ends of chain down tube to form a loop at end of pipe  place round nut and lever away works for me
[/quote]

I confess to being tediously wordy, but I think this is a case where an economy of words has me dumbfounded for the meaning.

Richrard L.

[nimrod650]

an old primary chain and a piece of pipe thread ends of chain down tube to form a loop at end of pipe  place round nut and lever away works for me

I confess to being tediously wordy, but I think this is a case where an economy of words has me dumbfounded for the meaning.

Richrard L.its a yorkshire thing short and to the point
[/quote]

[Triton Thrasher]

Use an old primary chain and a piece of pipe. Thread the ends of the chain down the pipe to form a loop at the end of the pipe. Place the  loop of chain round the nut and lever away.
 It works for me: I use it to remove the oil filter from the car as well.

A photo would probably help.

[chaterlea25]

Hi Sam,
My opinion is that the lockwasher is a waste of time, degreased threads and thread lock always work for me
Get or make the tool mentioned or the SRM nut, tighten to 65 ftlbs
buy or make a clutch locking tool, as described here
http://www.a7a10.net/forum/index.php?topic=3051.msg20654;topicseen#msg20654
and pictured here
http://www.a7a10.net/forum/index.php?topic=9646.msg70166;topicseen#msg70166

The hammer and punch method is barbaric!! also it does not really work as you have found out

John

[duTch]

 Sam, you say you "can't weld"- neither can I, but I managed to be able to knock up a tool much like the ebay one above except  I added a short 'skirt' (just the thickness of the nut flange, so to not have spring interference) around the outside that holds it on the nut nicely.

 To lock hold the rear wheel; last time I experimented with putting a 1/2" or so longer bolt in the Bottom of the two Rear inner chaincase cover bolt holes (on Plunger Models it's the bottom primary spring tensioner Stud).
    It needs to be in the right stage of the crank revolution (I think about 90º after TDC) which is easy to figure by poking a bar(Phillips screw driver)in the hole (if the tools goes in and stops, it's against the web), if it goes in more than 1/2" or so, no need to go more than 1",  roll the crank CAREFULLY backwards/forwards until it engages/disengages, and go in another ~10mm or so (the web is only just inside close to the case and about maybe an inch thick- one side>top< to undo, and other side>bottom< to tighten.)
   As some of us have discovered, if this bolt is too long it catches on the crank web, and makes a nasty knocking under normal operation , so I decided to use it to my advantage.

 I think some guys expressed concern over this, but I was surprised how easy it is, and how little force there was on the casing/threads, and if concerned about thread damage, grind the threads off the end that engage with the web.

 *I don't know if the Crank Web is big enough on A7's or ALL A10's to do this though

  phew!

[jachenbach]

I posted pictures about a year ago of what I used. It's a 1/2" drive socket that I bought for the front axle nut of a '71 Dodge 4wd pickup. Sorry I don't know what it was posted under.

[duTch]

  Try here;
http://www.a7a10.net/forum/index.php?topic=8995.0;topicseen 
     

[Sam C]

All

As always, you've been incredibly helpful. Thanks all for so many useful bits of information.

I've now ordered a tool (the one referred to elsewhere in this thread) to use with the existing nut. I think, with enough time and patience, I could have made something - thanks to the pointers on here. But, to save those hours I'm happy to spend the money.

I've also ordered a clutch tool, to grip the clutch. I don't have any old clutch discs knocking about, and it was only £8.50. Were it not so cheap, and if I had the clutch plates I'd have probably made that tool though - it looks better than the one I'm buying!

I'll take a look at the lock washer that I've ordered, but I suspect that in the end I won't use it. To be honest, I'm a bit confused about how it works! It looks like everyone on here is happy with 'lots of torque, and threadlock'. That's good enough for me too!

I'm pretty confident I can tackle this now, so I really appreciate all the comments. Doubtless I'll be back on again when things go wrong, but I'm in a much better position.

Cheers

Sam

[duTch]

 I have also added a non-stock washer (shim) behind the split-pin. No idea where it came from, just the right thickness but had to profile the OD to suit. All it does is take up any slack between the nut and s-pin in the unlikely event of the nut coming loose 

[Greybeard]

... related question: when re-fitting the primary chain case, do you soak the gasket in oil first?

Nah. Use gasket sealant if necessary. As with all mating surfaces make sure they are very flat. I used a smooth file, laid across opposite surfaces to remove any high spots. Other people have used abrasive paper on a piece of flat glass, ( clean off all abrasive particles afterwards ). Over the years Allen screws may have been used on the engine; they can be tightened far more than originally designed so can easily distort the area around the screw hole. The original slot head screws should only be tightened by hand, (retighten after fitting) and if the faces are good the case will not leak.

I used gasket sealant on my primary chain case on one side only simply to glue the gasket in place.

[Sam C]

Thanks both - that's every question ticked off, plus one I'd 'thought' but not actually 'asked' (Dutch!) A great forum this!

Thanks all.

Sam

[Sam C]

Gents

Just to say 'thanks again'. I fixed my bike back up in about two hours on Saturday evening. And on Sunday morning I was out on the road.

I did a smooth hundred miles or so, in beautiful early morning spring sun, and not a hitch.

I went with the SRM nut in the end, which I thread-locked on and torqued up to 65 ft/lbs.

I bought and successfully used a clutch tool, to hold the inner and outer together in order to tighten up the cush drive nut.

I used gasket sealant on the gasket for the primary chain case. It does actually leak a very small amount, but no more than I'm feeling is 'normal for a 60 year old BSA'! Next time I have to take it off I may take the other side off too and flatten them both to get a better join.

One very final questions:

On the clutch, I did take the plates out in order to fit the tool. When I put the plates back in again I simply tightened up the four spring nuts to 'about right' (with a few mm of thread sticking out the end), then checked that the clutch was functioning properly and disengaging evenly - and that was it. Ever since I've been worrying that those things may come off, since it seems a bit precarious to just 'do them up a bit and hope for the best'. What do others do? Thread-lock?

Or am I worrying about nothing?

Cheers

Sam

[morris]

One very final questions:

On the clutch, I did take the plates out in order to fit the tool. When I put the plates back in again I simply tightened up the four spring nuts to 'about right' (with a few mm of thread sticking out the end), then checked that the clutch was functioning properly and disengaging evenly - and that was it. Ever since I've been worrying that those things may come off, since it seems a bit precarious to just 'do them up a bit and hope for the best'. What do others do? Thread-lock?

Or am I worrying about nothing?

The cups and nuts have a ''notch'' that catches (more or less) on the springs. That should be enough to keep 'em from undoing. I had the same fear, but the nuts never moved a bit on my SA's 4 springer

[BSA_54A10]

Reading your original post again, I would suggest that you either have the wrong cush drive spring or it is just too old and has lost some tension.
You should be compressing the spring before it starts threading onto the nut and from about 1/2 down the nut should be very tight & hard to turn.
If you can do it up by hand it is way way way too loose and no wonder it keeps on backing off.