Vacuflush

[philarick]

Just bought a Four Winns Vista 348 and the vacuum pump keeps activating every 10 minutes or so. It cycles a few times, then shuts off. 10 minutes later it does it all over again. Head flushes fine.

[Lancerbye]

You have a little leak somewhere. Do you see water left in the bowl? Check for small pieces of TP caught between valve and seal.

[Ocean Cowbuoy]

there are duck bill valves in the system. probably 2 inline on the vacuum side of the diaphram pump as well as one just as the vacuum line leaves each head. they need replacing every so often as they get brittle and loose and don't close tightly resulting in slow loss of vacuum pressure which then engages your pump sporadically. have a look at the vacuum gauge for those 10 minutes to confirm vacuum loss to see if what I refer to is the problem.

[philarick]

Thank you. I'll take a look. They probably have never been changed. Hopefully they are easy to find.

[Ocean Cowbuoy]

they are situated in the flanges that bolt to the diaphram pump and to the vacuum cylinder on each head. they actually insert inside the flanges..make sure to order the same size and have the duck bill facing the same way as the one you took out. i recommend (for any repair) to take pics of it before and during your dissasembly so you can reference the pics when reassembling. learned that the hard way.

[peghall]

Originally Posted by philarick

Just bought a Four Winns Vista 348 and the vacuum pump keeps activating every 10 minutes or so. It cycles a few times, then shuts off. 10 minutes later it does it all over again. Head flushes fine.

Leaking duckbill valves are the most likely reason for the pump cycling for no reason between flushes. There are 4 duckbill valves in the vacuum pump--two on the inbound side, 2 on the outbound side. All four should be replaced every couple of years because--like joker valves in other toilets--the slits become stretched with use and cease to seal completely, creating an air leak. A drop in "vacuum" turns the pump on long enough to restore it.

You need a trouble shooting guide, which is in the owners manual. The V/Flush has changed so little except cosmetically since it was first introduced by Mansfield Plumbing in 1978 that age and model (model only applies to the bowl) doesn't matter...the same trouble shooting guide applies no matter which one you have. I've saved it to a PDF that I'll be glad to send to you or anyone else who'd like to email me (EMAIL, not a PM)...and I'll also attach a piece I wrote called "VacuFlush 101" that should help you reduce the need to trouble shoot it considerably.