I feel like the smell has literally permeated into the wood around the holding tank.
That's highly likely, but not just around the tank, but everywhere hoses have passed through and prob'ly all the soft goods (cushions, rugs etc) too, although it's unlikely that the odor
has actually permeated the woos, it's just attached itself to the wood. And, as someone else has already mentioned, a bilge
in serious need of a REAL cleaning
instead of just pouring more bilge
cleaner into it is also a likely culprit. But unless the tank is leaking, it's highly UNlikely to be the culprit...plastic tanks
don't permeate. So replacing it would be an unnecessary expense that solves nothing.
There is a product that WHEN USED AS DIRECTED!! can solve your odor problem: PureAyre
It's not an air freshener...it's the only product I've found that eliminates ANY odor. Not only will it get of diesel and residual odor left behind by stinking sanitation hoses, but PureAyre is also rated for use around food...which means you can even use it to get rid of the odor left in your fridge by the steaks or fish that spoiled when a natural disaster took out shore power for 3 days. Also does a great job on musty PFDs and foulies.
How to use it:
You can never eliminate any odor unless you first eliminate the source...'cuz as long as the source continues to exist, it'll continue to generate new odor. So first you have to find and fix any leak or replace the stinky hoses, then thoroughly clean the site, including every nook and cranny ...a good scrubbing with detergent and water, NO bleach. (A power washer can come in very handy here). Mop up any excess water and let the air dry till it's at least only damp...no standing puddles. Now you're ready to eliminate the residual odor. Use PureAyre full strength...I'd use pump garden spray jug set to a fine mist...it's so much easier than a trigger sprayer. A decent quality 1 gal jug will cost you about $15 @ Walmart. Spray every surface, nook and cranny...just a light spray. Do NOT rinse...just let it dry with hatches open so that plenty of fresh air can circulate. If the soft goods in the cabin have picked up the odor, just spraying it on the surface won't do much...you need to spray enough on carpets and rugs to penetrate to the backing...enough to penetrate cushions to the middle from both sides..not enough to make 'em drippy, just enough to get into the cushion....you'll prob'ly have to remove the covers and send 'em to be cleaned. Again, just let everything dry. If you still have any odor, you missed a spot.
A spray bottle won't go very far...plus, it's cheaper in the long run to buy it by the gallon...it has an indefinite shelf life, so just keep it on hand.
Someone else has also recommended that you get a copy of my book (see link in my signature...just click on the title). If you'll forgive a bit of shameless promotion, I agree because not only does it deal with every source of source of odor on a boat and how to cure, or better yet PREVENT 'em, it's actually a comprehensive "marine toilets and sanitation systems 101" manual that explains the laws, describes all the types of systems and how they work
, and will help you learn how to operate and maintain your system to prevent 99% of problems instead of having to cure 'em. 'Cuz you get to do any preventive maintenance
on your terms when it's convenient...the need to cure a problem never happens when it is! And I'm always glad to answer any questions it doesn't.
Btw...welcome aboard cruisers.com!