Bilge Sewage

[Gbetsch]

I discovered sewage in the bilge compartment under the aft head in my 2003 - 393. While it is not clear what the cause was, it appeared immediately after a pump out. I have examined all the pipes and connections accept for the connection to the external waste cap, which I'm not certain how to access. I found no obvious leaks. I did discover what appears to be a small leak from the underside of the tank at the plastic collar that connects the pump out pipe to the tank itself. However, it wouldn't account for the solid matter I discovered in the bilge. Any suggestions on how to proceed with the further diagnosis of the problem and/or repair of the collar leak would be welcome.
G

 

[Peggie Hall HeadMistress]

The "solid matter" you found in the bilge...

Is either just "primordial glop" in a bilge in serious need of a real cleaning, or is a buildup of waste that's been leaking from that fitting for a while...same as you'll find in a blocked tank vent. Most likely the latter if it's only directly under the leak.

The "collars" (female tank fittings) in plastic tanks are installed using a heat welding technique called spin-welding...a tool that melts the edges of the hole in the tank blends new melted poly with it to create the weld. Heat welding is the only way to join pieces of poly, 'cuz there is no sealant that will bond permanently to polyethylene. The weld for the tank discharge fitting has failed...most likely due to the discharge hose putting stress on one side of it, which would happen if a straight thread-barb fitting is used where a 90 or 45 should have been.

It MAY be repairable...but only if the stress that caused the failure is also eliminated, because the repair won't hold if there's any stress trying to pull it apart again. And you'll prob'ly have to remove the tank to make the repair.

Buy a stick of polyethylene...using a heat gun, melt it into the leak. Even enlarge the hole a little to be able to put plenty of poly into it. When you put the tank back be careful not to over-tightened the threaded hose fitting...just one turn past hand tight, no more.

While you have the tank out, clean the bilge...really CLEAN it this time, and flush ALL the dirty water out, instead of just dumping some kind of cleaner/deodorizer into it and calling it done. Once you have a clean bilge, mop up the excess water with a sponge and bucket or a wet vac...then spray the whole area--every surface, nook and cranny with Pure Ayre PureAyre Don't rinse...just let it dry, with hatches open so that plenty of fresh air can circulate for 24 hours.

Now you can put the tank back. When you do, this would be a good time to check the hoses for odor permeation and replace any that stink.

You'll find plenty of information in the discussions in this forum on the right way to clean bilges, how to test hoses for permeation and some tips that make replacing 'em easier and Pure Ayre. If you still have questions, I'll be glad t answer 'em.

 

[Rick I]

I discovered sewage in the bilge compartment under the aft head in my 2003 - 393. While it is not clear what the cause was, it appeared immediately after a pump out. I have examined all the pipes and connections accept for the connection to the external waste cap, which I'm not certain how to access. I found no obvious leaks. I did discover what appears to be a small leak from the underside of the tank at the plastic collar that connects the pump out pipe to the tank itself. However, it wouldn't account for the solid matter I discovered in the bilge. Any suggestions on how to proceed with the further diagnosis of the problem and/or repair of the collar leak would be welcome.
G

How did you get under the floor in the aft head? AFAIK there's no access there.

 

[Gbetsch]

You are correct there is no direct access, except for a corner which is accessible by removing the floor board directly outside of the aft head. That's where the sewage appeared. I recently purchased the boat so, I can't be sure if what I discovered was fresh or "primordial" as Peggy describes it. The bilges are very clean otherwise and the sewage hasn't reappeared. Not surprisingly, since the aft head has been placed out of commission while I continue to diagnose the problem. It is still a mystery to me as to where the sudden volume of material came from. That bilge compartment had been pristine only a few days prior to the discovery which, as I described earlier occurred immediately after a pump out.