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Help! Oil issues

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philward:
You mentioned you are running a custom oil tank, has it only happened since you fitted the custom tank? Just thinking whether tank internals affecting anythink

Bristolbadger:

--- Quote from: philward on June 02, 2023, 11:03:57 PM ---You mentioned you are running a custom oil tank, has it only happened since you fitted the custom tank? Just thinking whether tank internals affecting anythink

--- End quote ---
No the tank isn't a new addition and not had any issues with it in the past. Nice and clean inside and no blockages to report

K2-K6:
Possibly worth a run through of attributes in dry sump system fitted to those engine, maybe it'll prompt some further thoughts.

Scavenge pump should always return more volume than supply (else the system won't work) to keep sump area empty and all of volume available to the pressure side of pump to feed lubrication distribution.

Return pipe to tank should be above oil level on entry to tank. It can have air in return as it's just trying to suck sump clear when running.
Tank needs venting to avoid the return pressuring the contents, this usually has a air/oil separation to avoid oil being pushed out vent.
Could be vented to motor, but motor needs venting to avoid crankcase pressure building (they can't just constitute a closed system) usually this will be directed to air intake to avoid vent to atmosphere, or into a catch tank (also open to air) in case of oil being expelled.

The crankcase venting can't be dumped to oil tank (to use as a catch tank) it must be to atmosphere or into lower than atmosphere-ish, like an airbox to then ingest fumes into combustion.

Basically all the areas have to be effectively vented to atmosphere to avoid pressure building,  which is happening here. Somehow the tank etc is going over atmospheric, hence the oil just pumps out as soon as it gets a route that's unimpeded 

Too much oil for tank volume will cause a problem because the pump is trying to stash any available oil in there, but it should already have gone out the tank breather before you open the lid.

JamesH:

--- Quote from: Bryanj on June 02, 2023, 04:06:09 PM ---Sounds to me like you topped it up when it had been stood a while and oil tank had drained into sump

--- End quote ---
I'm fairly convinced this is the issue if I were a gambling man..

paul G:

--- Quote from: JamesH on June 06, 2023, 03:54:05 PM ---
--- Quote from: Bryanj on June 02, 2023, 04:06:09 PM ---Sounds to me like you topped it up when it had been stood a while and oil tank had drained into sump

--- End quote ---
I'm fairly convinced this is the issue if I were a gambling man..

--- End quote ---

When mine has been stood over winter I drain the sump first before starting it.
You would be amazed at the amount in there, just put it back in the tank. :D

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