I run my pump with the outlets at the top and have never had a problem
I've just had to return a booster pump to PureFreedom because it was leaking. They asked me which way up we had it mounted and I said 'inlet/outlets at the top'. They told me an electric pump with the pump at one end should always be mounted motor uppermost, so if there is a leak it won't damage the motor.
The pump may be mounted in any position. However, ifmounting the pump vertically the pump head should be in thedown position so that in the unlikely event of a leak, fluid will notenter the motor.