Shurflow head.

[Ted Christensen]

Again, I come to you experienced Searay owners for help.
My aft vac u flush head generator cycles every ten minutes for ten seconds. I have replaced the duck bill valves and the large washer that Carrie’s waste into the generator. The plunger on the generator does not show signs of wear.
So, that leads me back to the head where I’ve replaced seals. Tightened all the screws et. al.
Still cycling…
Any suggestions?
Thank you!!!

 

[AJSB]

Start with the head, is it holding water or does it leak out? If it’s holding water then leak is most likely at the vg. If you’ve already replaced the duckbills, it may be time to disassemble the vacuum pump and replace the bellows and seals. You could also have a faulty vacuum switch but they typically keep the pump from kicking on when they fail, not the opposite like you’re experiencing. To rule it out you could swap it with other unit (I’m assuming there’s 2 vg) and see if the problem follows the switch.

 

[Skybolt]

It's one of two things most likely, a leak or the vacuum sensor on the generator is bad or out of adjustment (worn). But since it cycles after ten minutes, it's probably a leak. Check the hose and all of the clamp's. If single clamped they should be double clamped. Also the line itself gets porous and can leak at high pressures like >20Hg.

After the cycle stops spray water around every connection and look for the water seeping into the connections or hose. Also you can add a vacuum gauge in line to monitor the vacuum and see what's actually going on.

 

[Little Ducky]

This could help you rule out your toilet.

Did you change out the "o" rings on your foot pedal?

 

[Ted Christensen]

Thanks, my next step will be replace the o
rings. May be a days, however. I discovered I contacted the Covid virus. I feel better if I’d been hit by a truck.

 

[brewster16]

I was where you are. I finally decided to put in a new vacuum switch and all the cycling stopped. I think I paid $170.00? Upon doing a side by side comparison I noticed the rubber diaphragm on my old switch was flattened and worn compared to the robust diaphragm on the new switch.