Dry Sump Info Needed

[Mesa]

Not sure if this is the right place for this inquiry, but here goes...
New to me - Sports racing car, mid-mounted BMW M3 engine, dry sumped. Drained the oil pan and feed lines to oil pan. Refilled with (ultimately) 3 gallons of oil. Cranked engine with ignition off to distribute oil, checked tank for level, repeat until level seemed secure. Car has been sitting for months and now the oil level is way down in the tank. Car has no oil leaks, and as I understand it, a sitting dry sump car's oil level will seek equilibrium over time. If so, how does one get the tank oil level back to 'normal' at this point? Cranking the engine (ignition off) does not seem to have any effect on tank level.

General dry sump oil change routine procedure would also be of use for my personal database.

Thanks in advance.

 

[Mesa]

 

[John]

rule one always check dry sump tank oil level with engine running at idle, level should be just under the top baffle,
when turned off the oil will drain back past the pump back into the sump, hence the low level in the tank.
kaspa

 

[Terry Oxandale]

I've never had any issues with the engine emptying the "equilibrium" oil out of the block, and back into the tank after sitting up a couple of months. I've never solely depending on starter RPM to pump it back through, being the starter RPM is about 1/10th my idle speed. I always check oil level immediately after shut-down.

 

[Jac Mac]

Is it an external multi stage pump?, if so flick the belt off and spin pump with battery drill until normal running pressure registers on gauge. This way you avoid any chance of air pockets, dry bearings etc with cranking whole engine.. As a rule of thumb-mine- the oil tank should be about 2/3 full with engine running, eg if tank is 3 gals capacity it should have 2 gal's oil & 1 gal air at idle. However some tank designs are not that simple, for example the pics recently of MK11 GT40 type posted recently.

 

[Jim Cowden]

My tank empty,s over time, well not completely.
It fills up the sump because its lower.
In the 9 years its been in use it sucks it out and pumps it back into the tank in no time flat.
I do have a breather hose coming off the old dip stick tube from memory, I did have to put a fuel line check valve on the line as it would shoot oil out if it stood for to long.
The check valve slams shut and sorted the issue.
Yes jacmac I know but I am getting old.

Jim