The BSA A7-A10 Forum

Technical => A7 & A10 Engine => Topic started by: Ron B on 07.09. 2011 00:34

Title: A10 oil pump
Post by: Ron B on 07.09. 2011 00:34
Hello everyone, I have a late 59 A10 that has a slightly stiff oil pump.  It turns relatively easy with a screwdriver in the tach cable slot but difficult to turn with my finger.  How stiff should these pumps be?  Finger turn or not.  Any help will be appreciated. Thanks Ron B
Title: Re: A10 oil pump
Post by: t20racerman on 07.09. 2011 06:28
Mine turns very easily by hand. As the A10 pump is a 'rotating gear' type, there really should be no stiffness - unless it is full of very cold SAE50 oil of course!  *smile*

You should certainly take it apart and investigate. You can't afford to take any chances with an oil pump. As a guess the bottom plate might have a 'pick-up' on it and addressing this on an oil stone might solve your problem.

Title: Re: A10 oil pump
Post by: Topdad on 07.09. 2011 11:02
HI Ron, yes, you need to investgate ,I had one breakapart , alloy or mattic i think it was called k??( hardened chewing gum ?) just disintegrated around the neck so check the case as well  .Mine went due to a bit of debris from the rebuild about a year after reusing the bike ,just at start up thank god , just felt slightly more resistance to the kickstart when starting followed by a a small unpleasant click and bingo no oil coming back to the tank. I'd always check that before setting off on a ride. Stopped it then and found no further damage just cleaned it outand fitted a new one. If you need a pump I've got a spare just lets me  know regards Bob H.
Title: Re: A10 oil pump
Post by: Goldy on 08.09. 2011 19:05
Be very carefull when you take it apart. Ensure that the gears go back in exactly the same positon. Don,t overtighten the screws. The only other problem is that if you make the pump too loose you will encourage wet sumping.
Title: Re: A10 oil pump
Post by: alanp on 09.09. 2011 08:23
My advice would be that if you have any doubts about an oil pump you should dump it and get one of SRM's. It's too critical a component to take any chances.
Title: Re: A10 oil pump
Post by: Ron B on 09.09. 2011 17:52
Thank you for the replies.  I took it apart, I know be careful, and found the bottom plate worn with both circles from the gears and the pin had dug a divot also.  I will take your advice, SRM here I come.  Ron B.