J/30 Class Association Forums J/30 Forum The Boat, Sails and Equipment Troubleshooting head issue

Ok - I'm clueless as to what is going on here. I've got the standard WC head and its fairly new - just installed ~2 years ago.

Having all kinda smell problems on an offshore race this weekend. We were pumping overboard (many miles offshore all night) and it seems like the head is somehow recycling the contents you are pumping out. Almost as if when you flush it, the crap (literally and figuratively) in the bowl is coming out in the flush water.

So a couple times there was brown water that seemed to appear in the bowel (presumable backing up from the output lines). When you tried to flush it the same brown water, but diluted seemed to come from the flushing holes - kicking up an aweful stench. After a while of pumping it would go clear.

Some facts:

- The head has always been hard to pump - hard enough that people comment on it. the old one was kind of hard to pump too

- I replaced the y-valve and the hose from the head to the valve, but the hose from the valve, to siphon break, and then to the overboard is old

- If I fill the bowl with fresh water (from sink) and pump, it drains. Its still hard to pump but not super hard.

- I've never seemed to get "good flow" when flushing - has always seemed to push more on the out stroke than what it pulls on the in stroke.

My ignorant theory is that there is some sort of partial blockage in the output that lets some contents out, but provides enough back-pressure to be hard to pump, and maybe so hard that a seal has been damaged in the head?

Any advice would be appreciated before I start just replacing everything in sight.

thanks - dan