Vacuum Flush assistance

[Sea Bandit]

Just purchased a 1988 300 Weekender and 5 days into purchase vacuum flush system does not create vacuum, any ideas or thoughts are appreciated.:huh:

 

[mmcguire2002]

When you say it doesn't create a vacuum, do you mean that when you step on the pedal nothing happens? Or, do you mean it won't seal correctly, so the bowl won't hold water and there is a slight hissing sound?

 

[Lazy Daze]

Yeah, can you provide some more details? Is the Vac motor running, does it continually run or will it stop? Do you hear leaking (hissing) anywhere - toilet, vac lines, vac fittings, etc?

How familiar are you with a VacuuFlush system?

 

[BruZerII]

If your system continually runs, it's the vacuum swith on the tank. There are problems with the pre-1990 switches. I bought mine from http://www.marinediscounters.com/servlet/the-10/Vacuflush-Vacuum-Switch-Assy./Detail
His price is actually cheaper than my local marine dealer could purchase it, let alone his mark-up. I replaced mine and the system now works correctly.
These prople are real good with any help on the vacuflush system.

 

[mmcguire2002]

Another obvious question...but if you just can't get suction period, are you sure you have it turned on? There is a switch for it on your AC/DC panel.

 

[Four Suns]

If your system continually runs, it's the vacuum swith on the tank.

I would disagree... it can actually be caused by several things preventing the vacuum tank from producing a vacuum... like bad duckbill valves, bad bellows, or something stuck in the duckbill valves such that they won't close all the way... It can be caused by a stuck vacuum switch but the more likely culprit are the duckbill valves...

 

[Lazy Daze]

I would disagree... it can actually be caused by several things preventing the vacuum tank from producing a vacuum... like bad duckbill valves, bad bellows, or something stuck in the duckbill valves such that they won't close all the way...

Or a crack in the plastic 90* elbow that leads into the vac tank...:smt101

 

[CJ Martin]

Or a crack in the plastic 90* elbow that leads into the vac tank...:smt101

I just had to replace that elbow. Whoever changed the duckbills last crossthreaded that on the nipple from the pump. Wasn't too bad a just.

Went to the boat todat and the vacuflush is still holding a vacuum from last weekend.

-CJ

 

[Bob M]

One of my buddies told me to shut the system down, step on the pedal to drain the bowl, put on a rubber glove, and wipe the area around the seal with some silicone on a cloth, being careful not to drop the cloth into the opening. He told me it makes for a better seal. Haven't tried it yet but he's being doing that to his boat for the last few years and his works just fine.

 

[Big Al]

I have a similar problem. I have a S type vacuum pump from Sealand. It worked OK for 2 days (boat was de-winterized recently and put in water 3 days ago). The pump starts every 10-15 minutes. This is what I have done up to now:

- Everything is fine with the toilet, no lost of water, no hissing sound
- The pump motor is working fine
- Replaced the hose between the vacuum tank and the pump assembly since there was a small hole under a collar. I still have the same problem
- I hear a a slight hissing sound that seems to come from the pump assembly. I opened the pump cover and the hissing sound is louder.
- Now I suspect:

- defective duckbill valve
- O-ring
- ??

What do you think ?

 

[Four Suns]

duckbills

 

[Big Al]

duckbills

Thank you. I will order replacements.

 

[Lazy Daze]

Hey Sea Bandit, it looks like we had a pretty discussion without 'ya! How'd you make out?

 

[electricaldoctor]

I have a similar problem. I have a S type vacuum pump from Sealand. It worked OK for 2 days (boat was de-winterized recently and put in water 3 days ago). The pump starts every 10-15 minutes. This is what I have done up to now:

- Everything is fine with the toilet, no lost of water, no hissing sound
- The pump motor is working fine
- Replaced the hose between the vacuum tank and the pump assembly since there was a small hole under a collar. I still have the same problem
- I hear a a slight hissing sound that seems to come from the pump assembly. I opened the pump cover and the hissing sound is louder.
- Now I suspect:

- defective duckbill valve
- O-ring
- ??

What do you think ?

I just installed a new "whisper motor kit" (#VAC311423) by Sealand. Although my cracked bellows was the only culprit in this instance, I opted to change everything as I had previously replaced the duck bills a few weeks earlier and that only leaves the motor to "crap" out.

~Ken

 

[WaterDoc]

Could be my problem....a cracked nipple on the suction side...you can't see the crack if it's facing away from you. You may try using a mirror and check all around this 1.5 inch nipple. Trying to find the nipple now though.