No, he hasn't cleared the vent yet.Mike,We've been trying to tell you two things:
1 clear the vent You seem to have done that, great. 2 Service the head you already have, it's a great unit. Since we've told you what you have, download the manual for it, which includes all sorts of good "How to service this toilet" information. Since you're smart enough to run a sailboat, you should be able to figure it out. Good luck.
It took me a while to realize there have been TWO people looking for help here..."Pat" in Kansas is the one who solved his problem by clearing the tank vent. Mike has bent over backward to avoid actually doing that. Pat's "standard" PH II is old enough that a new pump makes sense...Mike's PHC isn't, but that doesn't rule out the possibility that it needs something that makes it easier to replace than fix. He needs to find out WHERE in the system the problem is...'cuz if the toilet isn't the problem, a new pump won't solve it.