Hi Mark - I had a similar problem with our Sealand China Toilet on our first camping trip this year. I noticed a small amount of water on top of the toilet and on the floor behind it whenever it was flushed. I removed the plastic cap on the top rear and discovered that the vacuum breaker assembly was cracked and was allowing a small amount of water to leak out whenever flushed. It is obvious that I must not have gotten all the water out of the assy when I winterized the trailer last fall and it probably froze up thereby cracking the assy. Fortunately, while on the camping trip, I had a tool kit that had short scredriver bits that you inserted into a handle for use. I used the philips screwdriver head and a small pair of channel lock pliers the maninulate between the plastic cover and the wall (only about an inch of working space) in order to remove the plastic cover and reveal the vacuum lock assy. We were able to control the water leakage throughout the trip by keeping wads of paper towels around it and on the floor. Upon returning home, I called Sealand to order a new vacuum breaker ($33), also ordered a new hose ($1.06) that goes from the lower flush pedal asssy to the vacuum breaker, as I was only able to cut the original hose to remove it, so it was too short to reuse without straining it to much. Order these parts at the same time, as I did not so had to pay a lot for shipping on two different orders. the sprayer hose has a lot of excess so that one was not a problem. Should this be your situation also, you should be able to determine the parts you need from the data package provided with your Sunline. If you need any more information, let me know and I will help you out as much as possible. Additionally, I will follow the winterizing instructions in the Sealand info this coming winter. Last year, I blew all the lines out with an air compressor and then pumped antifreez thru the system, but that must not have been sufficient to protect the vacuum breaker from freezing. I am interesting in hearing what your problem actually was when you determine the cause. Good luck!
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