Odor from my toilet / holding tank

wipe superlube grease on the gasket every 3 months (where the ball opens, with the ball open) as Sealand recommends it and it helps the gasket seal and keeps it lubricated.

Sealand also has a bowl seal cleaning stick that you should use every couple of months to keep the seal clean. Or an old tooth brush will work.

Aaacckk

And man you better mark THAT toothbrush in such a way that there is NO doubt what it is for............

No need to mark it. Just use hers.

Some good advice and bad advice here.... Yes metal lines could be used, but you need to be very specific about the alloys used. Some of the stainless alloys are okay, and Monel is fairly good too, but the problem occurs two fold: welded tanks always have problems at the weld first. This is because the metallurgical qualities of the material change somewhat when welded. The second problem is whether the urine is mixed with a number of other components, including seawater, which obviously has a sodium content. Unfortunately, it has more than salt content. Those familiar with drinking water treatment regimens would remember the trihalomethane problems, when chlorine is introduced to organic material, and the issues that result. The same is true in sewage treatment, since the rinse water source could contain a whole host of other contaminants.

I generally recommend plastic tanks and modern sanitation hose for boats under fifty feet. Larger boats need a more comprehensive study of what kind of system is going to be installed and what materials are the best choice.

Here is an excellent site on corrosion resistance from the chemical industry. It has a pretty good list of metal and plastic corrosion data:

http://www.nibco.com/assets/ChemGuide.pdf

Long story short, your classic Chris Craft should probably have a new plastic tank and some good quality modern sanitation hose installed. All in all a reasonably simple and inexpensive fix.

Some one here mentioned Peggy Hall best advise is google her and buy her book. She has an email address, don't have it since I sold the boat, but she is the foremost expert on this subject and will answer your questions. When I first got a boat she was a great source of advice. Contact her and you won't be sorry.

Does anybody else have her email?

I once got pulled into troubleshooting a friends head after he’d had some work done from a now non responsive yard. The vacu flush would pump nonstop and the toilet itself seemed to have little suction and they were pushing the solids down for a weekend to get by. I removed the hose from the vacu flush pump and found the vacuum was great and the switch worked fine. Moments later I realized the yard that worked on it didn’t connect or properly connect the sewage line on the bottom of the toilet. It was sitting in the bilge right under the head. That explained the smell.

I do have her email but i would suggest you post on the trawler forum she monitors it . Sounds like you found the problem but now you have the bilge full of it That sucks .