Pump-out problem

doorpro

Cadet
Joined
Nov 27, 2010
Messages
8
Hello all,

It's been a while without anything to fix however I have an issue that has always been an annoyance and Its time to ask what I need to look at aboard my 2000 Silverton 453MY.

Pumping out is never a problem however when the pump-out guys try to fill the tank with fresh water to flush the tank a few times the fresh water never wants to go back in. I have always held a rag around the hose in the filler and that helps.

The pump-out guy says that it's a filter that needs removing but I have checked the two breather lines leading to the thru-hulls and there are no filters which I already knew but checked again. The 100-gal holding tank has two breathers at the top of the tank, one to port and the other to starboard.

I have just removed both hoses from the top of the holding tank and flushed them with fresh water and a bunch of crud flowed out that most likely happened when the tank got over-full and I thought that now the tank can breathe and there will be no problem getting fresh water in there, but the same thing is happening, the water just gushes back out.

The only other thing that I can see is that where the hose comes into the engine from the stern inlet/outlet it makes a sharp 90 to the right to continue to the holding tank and a sharp 90 to the left to the macerator and I'm wondering if this is causing a flow back. BTW the macerator works great.

If anyone else is having this issue with the 453 or any Silverton yacht I would love to hear from you because the pump-out guy is a bit of a loud-mouthed know-it-all and his rants about filters is getting old.

As Usual thanks to you all for taking time to read this.

Regards,
Doug.
 

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
42,063
If I understand you correctly, the tank is not breathing, same as a gas tank that doesn't have a vent

If the breather lines have a loop in them then there may be water/crud in the lines. Use compressed air to blow them out.

Can also try to flush tank with breather hoses removed

Either that or there is a loop in the suction line where liquid can pool
 

doorpro

Cadet
Joined
Nov 27, 2010
Messages
8
Hi alldodge,

thank you for your reply and suggestions. I did in fact clean out both breather hoses initially and it helped somewhat.

However, after further investigation I found that all the hoses from the filler/pump-out to the Macerator and from there to the tank were all partially blocked due to years of use and it wasn't something that could be flushed out. The original 1.1/2' ID hoses were down to about 1/2" so it was now simple to see where the problem lies.

So, I bought and replaced all the hoses, and everything is back to normal now. The tank not only pumps out with ease now but partially filling back up to flush a few times is perfect with no backflow.

Man that 1.1/2" ID hose is damned expensive and there was 30' to change but I feel much better knowing that everything cleans out now.

Once again, I thank you for your help.

Regards,
Doug.
 
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cyclops222

Lieutenant
Joined
Mar 21, 2024
Messages
1,305
Can not cheap out on sewage parts to prevent germs attacking people and food on a boat. (y)(y)(y)(y)
 

doorpro

Cadet
Joined
Nov 27, 2010
Messages
8
I guess I got really lucky because I have owned this boat for almost 18 years now and I never ever got any bad smells from the tank and to be honest I wish that I had because i would have looked into solutions when I got the first wiff. But now all is well and like I said I always use Dometic tank and bowl treatment which really breaks down the waste and makes everything smell much better.


Dometic D1112001 3 N 1 Bowl Cleaner & Tank Treatment
Combines air freshener, bowl cleaner and tank treatment all in one easy to use drop-in packet.
Rapid-dissolving packet releases effervescent cleaning action. Enzyme formula naturally neutralizes tank odors. Lavender scent. One 1.5 oz. packet treats 40 gal. tank.
 
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