Wet Sumping

[alanp]

I know wet sumping can't be avoided without fitting a valve (manual or auto) on the oil tank feel line to the engine but is there any way the little ball at the end of the suction pipe above the sump plate can be seated better on the inside of the pipe? I haven't taken this area apart any further than the sump plate but oil just keeps dripping out of the pipe and I can't see any obvious way of getting to the other side of the ball.

[beezalex]

Alan, it's not the ball in the pickup tube that prevents wetsumping.  That's in the return and so just keeps some oil in the return line so that the topend gets oil right away after starting.  The ball valve of interest is in the right hand case and is only accessible with the crankshaft removed.  Replacing/reseating it does, in fact, help prevent wetsumping.

[a10 gf]

Welcome to the forum, Alan. here is a picture of a (defective) anti wet sumping ball and spring. http://www.a7a10.net/forum/index.php?topic=848.0


It's parts 21-22-23 on the crank diagram.
http://www.a7a10.net/BSA/techpics/crankdrivescan.jpg

Try a forum search for wet sumping. See http://www.a7a10.net/forum/index.php?board=15.0 for search info.

[BSA500]

Also don't dismiss the possibility that the oil pump may be worn/need attention.My A7 always wet sumped and was only cured after the pump failed(not saying your pump is dead) and I had it rebuilt using a cast iron body.May also be some crud preventing the ball from seating.

[alanp]

Thanks everyone. I wasn't going to pull this engine apart (only had it a week or so) but I'm now 90% certain that I will. After I've had the frame powder coated and rebuilt the rest of the bike that is.