VP SX drive low oil but no sign of leak

[swift1]

Hello all,
I have a new to me 2003 Chaparral 220 with the Volvo Penta 5.7 with SX drive. I checked the drive oil the other day and the dipstick was dry, so I decided to change the oil. I drained the old, it was a bit dirty but no sign of water intrusion. I pumped the recommended 2.1 litres of oil through the drain hole, but no oil came out the vent hole. The dipstick is still dry. There are no signs of leaks coming from the drive or in the bilge. Any ideas as to where I should be looking to see where the oil is going? Bellows?
Anyone else run into this?
Thanks

 

[Horigan]

Keep adding oil. Make sure the drive is level. I can’t remember the value, but I think it’s more than 2.1L.

 

[Scott Danforth]

did you pressure test when it was empty of oil?

If not, keep adding oil until its on the dipstick. then monitor. if it continues to drop, you have a bad seal

 

[swift1]

I did not do pressure test but I'll go ahead and add more. 2.1 litres is the recommendation for the SX though, so I'm thinking there must be a leak. I'll update after.

 

[cyclops222]

No oil sheen on the water ?

 

[swift1]

No sheen. Just added another half litre and it's now reading on the dipstick. So about 2.6 l altogether to fill it, not 2.1. I'll let it sit overnight and check again tomorrow to see if the level stays. Thanks for all the suggestions.

 

[BRICH1260]

Always fill until it flows from the upper side vent screw hole. It is possible that you could have a driveshaft seal bad and that the oil has gone into the bellows. Now that you have the oil level registering on the dipstick, run it for a while and check it again to see if it has fallen. If not, you should be good.

 

[Donald0039]

There is really no place for the gear oil to leak out of that you cannot see. It's not like an engine and oil where the engine can burn oil.

I would just keep adding oil until it comes out of the vent.