Marine head won't pump
Hi, really need help. I have a Raritan PHII manual head. Was working fine but
got a lot of use in a couple weeks, and suddenly, pump extremely hard to push down. If I wait a while, I manage to pump down, and waste water goes down without a problem.
But quickly the pump builds up pressure again,and I can't push down lever.
I've checked the tank vent line, no problem there. And I've emptied the tank.
HAVE not checked waste line from pump to tank as it's very hard to get back there and get hose off coupling.
I don't think this is blockage b/c if I wait it is pumpable. I did have toreplace the "flush- dry" valve recently,and think that's installed properly.
Suggestions for troubleshooting? Is it a problem with piston?
Thanks for any help. God, heads are one part of boat work I could do without!