The BSA A7-A10 Forum

Technical => A7 & A10 Engine => Topic started by: TRIPLET on 10.10. 2009 19:39

Title: wet sumping problem
Post by: TRIPLET on 10.10. 2009 19:39
     my mates Rocket Goldie is wet sumping so bad that after running for no more than a couple of minutes around 1.5 pints of oil are blown out of the breather hole in the l/h crankcase.after stopping the engine he drained the rest of the oil in the crankcase via the bung in the sump plate and then started topping up the oil level only to find it was coming out of the drain plug almost as fast as he was filling the tank.the oil tank has recently been re-fitted after painting and this is the first time it has been run since,it ran fine before with no wet sumping,the oil pipes are connected the right way round and we are now both puzzled as to what is causing this,could it just be a coincidence and could it be something like the oil pressure relief valve stuck open,any help would be appreciated.
Title: Re: wet sumping problem
Post by: muskrat on 10.10. 2009 20:53
Sounds like the oil pump has fallen off !! even a bad wet sumper would take a couple of days to loose that much. Double check hoses are right way round then check the pump, swarf from tank may have eaten the punp.
Good luck.
Title: Re: wet sumping problem
Post by: MikeN on 10.10. 2009 20:57
If oil is coming out of the sump  as quick as you can put it in the oil tank I would say you have got something seriously wrong. Has your oil pump come loose (Do you actually have an oil pump in there?)?
  Dont run the engine again .Take the timing covers off and investigate .
Title: Re: wet sumping problem
Post by: BSA_54A10 on 13.10. 2009 02:48
This sounds like the scavenge pipe is blocked.
The tube can get rusty when laid up for a long while so when the oil pump draws the oil in the ball bearing gets stuck on the rust and partially blocks off the return "suction" pipe