if you do strip it down and have the sludge trap cleaned, the flywheel bolt that also secures the sludge trap really should be replaced with a new one , how I know this?My local engineering firm, cleanede when I had the timing side bush replaced,? well they did not replace the bolt and after 50 years the bolt decided to strip the threads in the flywheel then drop down into the sump chamber, whilst I was riding up the M4 at 70mph and smashed both crankcase halfs, srm had the bolt in stock and a week later and £350+ lighter Steve Mcfarlane had repaired both crankcases and restored the crankshaft and the bike is still running, that was about 18 months ago
The short stroke A7 doesn't have that bolt, only the LJ A10 cranks. Not sure of the early long stroke.Cheers
Having gone through my Long Stroke A7 this past winter I've gone the route. Long stroke trap plugs are smaller so you will have a screw slot not a hex. They come out reasonably easy with a little heat and a impact screwdriver. To just check the sludge trap it will entail taking the whole package out of the frame. A good two day project out and back in. There is no tube inside the crank as the later A10's have, just a place to catch gunk. A filter is the only way to go. These engines are quiet (kind of) so you will hear if something is going bad.
the bolt decided to strip the threads in the flywheel