I've got a 1990 Sundancer 350 with...

[jimboc]

I've got a 1990 Sundancer 350 with a vacuum flush headsystem and  Sometimes after flushing  And bringing in some fresh water to refill the bowl and then putting the foot actuator back in the neutral position so it is no longer bringing in water, sometimes the vacuum will suck the water out of the bowl until then you hear a hissing sound.  Sometimes it occurs after someone flushes toilet paper which gets caught between the rubber seal and the curved sealing valve,  So I will take my finger and run it along the entire edge of that seal to clearany debris and it will seal but not every time. sometimes depends on the position it will continue to leak water and then hiss air any suggestions

[PJS]

You need a new ball valve seal. They damage pretty easily, especially when cleaning to aggressively.

[jimboc]

Does the whole head have to be removed from the boat to access the ball valve seal or can just the top half (bowl) be removed to access that seal while it is in the boat?

[Dave_F]

Pretty simple fix. The entire bowl will lift off the base (2 piece base) and it is a simple matter to change out the gaskets and seals. Make sure to have some silicone grease to lube the seals when installing the new ones. There are numerous YouTube videos to show how this is done. While in there, make sure to replace the inlet valve parts as well as they have about the same service life. Ours was leaking around the seals on the ends of the shaft that rotates the closure mechanism and you will get vacuum leaks if this is not perfectly sealed causing constant cycling of the system. Buy a rebuild kit and replace everything in the kit as it all wears out eventually. Rebuilding the vacuum unit in the engine room is a much bigger and nastier job, but eventually, you will need to tackle this as well. These repairs are easy DIY repairs and do not require specialized tools or training. Best of luck - have fun.

[PJS]

Dave F. is spot on. I always replace ALL the parts when it is apart. Nothing worse than to have to pull apart again to replace another older part that did not like being disrupted. Simple process.
I found cleaning the ball valve and bowel after every cleaning with Pledge works well. Lubricates the ball valve and does not harm the poly components. Prevents solids from building up (at a micro level) and damaging the seal....

[jimboc]

Dave or PJS thanks, any advice on where to order the to buy the inlet valve parts or rebuild kit? and what to ask for

[PJS]

Go to Sealandparts.com. They call all things Dometic Vacuflush. They will be able to direct you... you can buy individual parts or partial rebuild or full rebuild kits.

[Dave_F]

<> VacuFlush Toilet Kit - Marine Sanitation & Supply. This is the complete kit including the water valve and I highly recommend changing out all of this. They have another kit without the water valve for around $45 or so, but take my advice and buy the whole kit.



Dave Fuller

1124 Regiment Drive

Acworth, GA 30101

770-421-9902 home

404-697-3153 cell

[email protected]

[jimboc]

THANKS! I see there a 2 choices on the link you sent, Eco Ball and Standard Ball... do u know which one I need or how to know?

[Dave_F]

It looks like the standard has a metal arm underneath the plastic pedal and the Eco has an entirely molded plastic arm without the metal. My 2005 Sundancer has a metal arm with a plastic pedal (standard one).



Dave Fuller

1124 Regiment Drive

Acworth, GA 30101

770-421-9902 home

404-697-3153 cell

[email protected]

[JRT]

Weekend fix-- Put a rubber glove on, dip your index finger in some vaseline and apply it to the rubber seal in the base of the bowl. Not a permanent fix, but should work for a few days, did on my Vac-U-Flush before I installed the kit with new seal. BTW, change the water valve while you have it apart as Dave said. It;s part of the kit and you can change it easily while you have everything apart.