Replacing duck bill valves
- Thread starter HOGAN
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2 on each side of the pump... If you have a vacuum generator with the pump mounted of top (instead of stand along pump / vac tank) you may have to unscrew the pump off the tank.
Put some paper towels under and around the fittings
Remove the clamps on both sides. Sometimes you don't have to pull the hoses off the barb and you can just unscrew the fittings leaving the hoses on. You have two fittings on each side, remove them to pull the old DB. Scrape the deposits around the fittings., put the new ones in with liquid soap on the flange and reassemble.dont overtighten or you will distord the DBs.
Like everything else, if you have good access and it all goes well it s a 10' job... Or it can take 3 hours
Put some paper towels under and around the fittings
Remove the clamps on both sides. Sometimes you don't have to pull the hoses off the barb and you can just unscrew the fittings leaving the hoses on. You have two fittings on each side, remove them to pull the old DB. Scrape the deposits around the fittings., put the new ones in with liquid soap on the flange and reassemble.dont overtighten or you will distord the DBs.
Like everything else, if you have good access and it all goes well it s a 10' job... Or it can take 3 hours
Mike it's pretty simple are you working on a SeaLand VacuFlush vacuum generator or their waste transfer pump?
A VacuFlush requires 4 duckbills. They are installed in pairs with a vacuum generator and only one duckbill is used on each side for the waste pump.
The duckbills always point in the direction of the flow.
You need to loosen up the clamps on both sides of the pump and unscrew the coupler. Pull the old out and replace with new duckbills.
It's pretty simple, I'm looking for a link with photos that isn't another boating site.
Bill
A VacuFlush requires 4 duckbills. They are installed in pairs with a vacuum generator and only one duckbill is used on each side for the waste pump.
The duckbills always point in the direction of the flow.
You need to loosen up the clamps on both sides of the pump and unscrew the coupler. Pull the old out and replace with new duckbills.
It's pretty simple, I'm looking for a link with photos that isn't another boating site.
Bill
- Joined
- Mar 2, 2000
- RO Number
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If you can, dismount the pump prior to unscrewing the bill holders or hoses and insert a heavy duty trash bag under it. The point is to try and capture the "water" that is certainly there. You don't want that all over the bilge.
Prior to getting started, clean the bowls with lestoil or something like it and flush several times.
Prior to getting started, clean the bowls with lestoil or something like it and flush several times.
Pascal +1 on the soap, not overtightening and cleaning the mating surfaces.
I agree it depends on the location of the vacuum generator or the waste pump as to how easy or difficult replacing the duckbills will be...
Bill
I agree it depends on the location of the vacuum generator or the waste pump as to how easy or difficult replacing the duckbills will be...
Bill
- Joined
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- RO Number
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- 6,625
So much for putting a bag under the pumps. If you loosen the clamps they should spin out pretty easy but it looks like Pascal called it. To get the pair in between the pump and vacuum chamber you will most likely have to pull the pump and that means disconnecting the wires to the motor. These are DC so remember how they are connected.
You might want a fan nearby.
You might want a fan nearby.
is that one vacuum pump and one waste pump or 2 vacuum pumps?
If both are vacuum you need 8 duckbills or 4 sets, if the other 6 duckbills or 3 sets.
I just looked again you need 4 sets of duckbills or 8 total.
Bill
If both are vacuum you need 8 duckbills or 4 sets, if the other 6 duckbills or 3 sets.
I just looked again you need 4 sets of duckbills or 8 total.
Bill
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Looks like two vac gen side by side so it s 8 DB total.
Only the pump used for overboard discharge uses 2, if it s for flushing (vac gen like in this case, or stand alone pump with separate vac tank) it s always 4
Be careful with the white fitting on the inlet side, it s not very strong and doejstvgae very well. If it cracks you have to order a replacement dip tube, happened to me a few months ago. Not expensive but takes a few days
If the discharge hose goes downhill it will be pretty empty. If it goes uphill to the tank, it will be full. In that case undo the inlet side (dip tube), unscrew the pump and lift it up
It you have ever changed diapers, changing DB on a VF is a piece of cake!
Only the pump used for overboard discharge uses 2, if it s for flushing (vac gen like in this case, or stand alone pump with separate vac tank) it s always 4
Be careful with the white fitting on the inlet side, it s not very strong and doejstvgae very well. If it cracks you have to order a replacement dip tube, happened to me a few months ago. Not expensive but takes a few days
If the discharge hose goes downhill it will be pretty empty. If it goes uphill to the tank, it will be full. In that case undo the inlet side (dip tube), unscrew the pump and lift it up
It you have ever changed diapers, changing DB on a VF is a piece of cake!
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- 6,625
Pascal I will not second that! At least with a diaper it doesn't run down your arm when the hose slips and the fittings wobble.
Then there's the opportunity for the "splash". You are working it loose and have the hose stressed a bit. You twist turn and pull and all of a sudden the hose comes loose and the whip of the hose sends a splash of goo into your face.
Don't forget to lick your lips.
Then there's the opportunity for the "splash". You are working it loose and have the hose stressed a bit. You twist turn and pull and all of a sudden the hose comes loose and the whip of the hose sends a splash of goo into your face.
Don't forget to lick your lips.
Capt. Bill1
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Flush a bunch of bleach/water mix or PineSol/water mix through your system before you start the job.
Pulling out the pumps is not a big deal. And it gives you a chance to clean the tank around and under the pumps. The wiring looks properly color coded. But even if you did some how reverse it, it's a diaphragm pump so it doesn't care which way it runs.
Pulling out the pumps is not a big deal. And it gives you a chance to clean the tank around and under the pumps. The wiring looks properly color coded. But even if you did some how reverse it, it's a diaphragm pump so it doesn't care which way it runs.