On our 90 201 with a 200 Johnson the water psi at WOT is right around 18-19. The prop shaft is 4 1/2" below pad. I've been told that for the motor being that low the psi's are to low and that the water pump maybe going out. Is this true? We want to raise the jackplate but don't want to burn it up. We just got it.lol What's the lowest the psi can go and still be safe?

Also what's the max rpms for it? 5800?

Thanks