Holding tank exhaust on a 1989 silverton

You will generally have one vent for each fuel tank and one for each holding tank. If you put your nose to it you should be able to tell which is which. It should also be in close proximity to the holding tank.

This early in the season you may also be dealing with the dreaded "Brick". If you don't pump out often or completely enough the waste can settle into a brick in the bottom of the tank. Since 1989 that could be a big brick showing you a full tank, but no lose stuff. Each time you pump out you should put in several gallons of fresh water and then pump that out. Personally I don't know of any chemicals that can undo a brick without hurting the tank or "pipes". Maybe someone else here does. In the mean time we'll just hope it's the vent.
One spot of possible good news. More often than not when I've seen boats unable to get pumped out it's the pump that doesn't have enough suction. Try another pumpout station before getting too dirty.

Big mistake! I'm hoping someone will come on here with a chemical. Failing that it's replace the tank or stir it up. Always empty the tank before winter layup and every couple of weeks during season. Better still direct everybody to the shore facilities. Good luck.

It's a very simple thing. Whether you're talking mud or c---. The solids fall to the bottom, the water rises. 6 months of no shaking and the pump out only takes the water on top. With home septic tanks you should put in a chemical like Rid-X that eats the ---- so the liquid can leach into the surrounding soil or else the tank volume shrinks and you bring in the big pumps. Eventually the bottom dries too much for the pump and it's time for a new septic tank, usually about 30 years or so. On boats we call it a brick and this boat has had 20 years to build it up. In a tank that was probably just 20 or 30 gals new that could do it.

If your pick up is on, or very near, the bottom, as most are, how does this brick get so big?

A small tank and 20 years of not pumping out regularly. Try filling a 5 gal paint bucket half way with mud. Let it dry then fill the rest with water. Now tape a cheap shop vac to the pour hole above the water and see how much of the dried mud comes up.

You can use one of these liquid product for home sewage clog in the pipe to the sceptic system. It is a brutal product and will make a brick, and yes they exist, quite more fluid.
I used it, and worked fine, unfortunatly I don't have the brand in my head. I find it on a hardware store.
Good luck.

Have you ever had a milkshake? Take a big pull on the straw, and you'll suck the milkshake right around the straw up, but there's still a lot of milkshake left in the cup.

It's probably more often a northern thing because of length of season and (in)frequency of boat use away from the dock, especially this year with such frequent rain and cool weather.

That quote made me laugh out loud.
It proves that you are kind at heart..........

When I was in Georgetown earlier this year a small cat with 4 guys on board transporting came in a bit past overfull. You would not believe how far the S... flew when that cap came off. Think Old Faithful. Yuk.

This was also in Georgetown, Md.
A freind of mine was trying to pump out his tank.
Nothing was happening.
Another friend on the pier said to him" have a look in there & see if it's clogged......"
It wern't.
The geyser errupted.
He was coated head to toe.
He turned and walked right off the pier into the river.
The rest of the week end the guys kept telling him he a piece of corn in his teeth.....

And how long did it take for you to live down the name of "S---head"? I hope the owner bought you dinner (after a CLEAN shower).

Holding Tanks

A 24x24 by however deep tank has a 576 square inch surface area using nothing more than a old handpump style joker valve weighted flapper seal assembly, it is possible to pressurize the tank with a plugged vent to a CATASTROPHIC condition with very little effort ,1/2 PSI on top equals over 250 at the 1 1/2 drop tube opening that is connected to the deck fitting!

crap happens