Ever hear the expression "squeaky wheel gets
the grease?" Your head is telling you it needs lubrication. A manual toilet consists of a piston (the part with the handle on it) inside a cylinder. The piston has rubber seals on it that rub against the cylinder wall when you pump it. Without lubrication, it creates dry friction that wears the rubber pump seals and o-rings and the cylinder wall. It's even worse in salt water because salt crystals scratch the cylinder. Heads come from the factory slathered with teflon grease...it lasts about two years. When it start squeaking, it's time to lubricate it again. Using it without lubricating it wears out the seals and gaskets very quickly, so it should be done as soon as it starts to squeak, or better yet every fall as preventive maintenance. You CAN buy lubricants that are just poured down the toilet (some people use a little vegetable or mineral oil), but they wash out very quickly...you have to do it about once a week. Taking the pump apart once a year to slather it with Sea Lube or SuperLube keeps it working smoothly and efficiently for at least a full season...plus, it keeps the seals, and valves from drying out which cuts down on the frequency of rebuilding. The best time to do it is to make it part of winterizing, so the teflon grease protects the seals, valves and o-ring from drying out and becoming brittle over the winter. And, taking it apart to lubricate it has the added advantage of providing an opportunity to inspect the pump seals and o-rings to see if they need replacing BEFORE they fail...doing it when the head is clean and dry is SO much nicer than doing it when the bowl is full and won't go down! Teflon grease is sold at all the boat stores as SeaLube or SuperLube. A liberal "dose" of it will keep your pump working smoothly for at least a year, maybe two.