Upside down Crank seal?

[Large]

Hi,
Im rebuilding a 1996 force 50hp My manual is unclear but seems to instruct me to install the lower crank seal with the tension spring facing down toward the drive shaft, away from the engine case. The marks on the crank are spaced in a way that seems to indicate that the previous seal was upside down as well.

I can only think of a few reasons why the seal (might) be upside down.
(Because unlike a 4 stroke the crankcase is under vacuum instead of pressurized?)
(Because it will stop water from being blown through to the bearing by the exhaust ?)

I can't clearly understand the directions in my manual and there are no pictures to help I've even tried to look at power head pics on ebay and etc.but cant find anything to help.

If anyone knows the answer I would greatly appreciate any help.

Thanks

 

[Nordin]

It can depend on how the lip/lips at the seal are formed.

I have restore a lot of OBs, many Chrysler/Force and other brands too and I have always assembled the crank seals with the spring faced away from the engine block.

Upper seal spring faced towards the flywheel.
Lower seal spring faced towards the drive shaft.