B/c the weather sucked here, I finally broke down and pulled the guest head from the wall over the weekend. Mine is the Atlantes A5 Series with a diaphragm pump, not an impeller. The pump looks the same as the fresh water pump. I pulled the diaphragm apart to inspect it and believe it looks to be in perfect working condition. With that said, I don't know what a bad diaphragm looks like...... I put it all back together and then I tightened all the intake hoses to try to stop the air leak.
The maserator has a clear window so you can see if anything is obstructing it. Upon inspection, I could see a heavy cotton string wrapped around the blades. Hmmmm? I wonder what that could have been.....ladies! $%!#$%$%&##$%!!!!!!
I opened up the maserator chamber and used the LONGEST needle nose plyers to pull the giant cotton ball and string out of the blades. When I put the toilet back together I bolted it back down, it purred like a kitten, however, the water intake still is losing its prime. So, it's still taking 2 cycles to get the job done.
do you have a strainer in the line? it could have a bad gasket.i just did my strainers and replaced all my intake hoses.
A bad diaphragm can allow the water to drain back, and if it's bad enough, it won't pump at all. The little rubber valves can warp with age and not seal, allowing the leakage. A new diaphragm or "kit" (depending on the pump) will fix the problem, and it's a whole lot less expensive than a new pump!
42Gibson: Yes, I have the standard issue Raritan strainers. They only have a simple O-Ring for a seal. Over the weekend, I'll pull them off and rub some white lithium grease on them to see if that improves anything. I inspected them before and they seemed OK.
Stmbtwle: I agree that the gaskets can be worn out, but I didn't really see any signs of wear on the diaphram. I was hoping to find debris coating the surface or caking the intake hose, but nothing. Raritan tells me the diaphragm rebuild kit is ~$50. It's a last resort, but can easily be completed. There's only a couple more things I have left to check before I give up and start spending more money.
In my experience the diaphragm didn't "wear", but the valves did warp to the point they wouldn't seal. However it WAS a different make of pump from what you have.
Seems to me this could be checked easily enough without disassembling the pump. Disconnect the hose at the toilet end, fill the hose with water and see if it drains back. If it does, the water is either going back through the pump or you have a leak.
I've had the same problem with a manual toilet too, where the rubber valve plate warped and wouldn't seal.
mine has perko brass raw water strainers right after the thru hull,thats what I rebuilt. the gaskets were cracked and sucking air.
I need to correct what I said earlier. After doing some research, my pump is a diaphragm model not impeller. Model 4405-143. I can't decide if it needs a rebuild kit yet. I am going to try Stmbtwle's water test. I hate to be dense, but where do you mount the 1" vented loop you guys are talking about? Doe it have to be above the head?
Check out Raritan's website for installation diagrams of their toilets. I think it illustrates where the vented loop should go. I've about decided I don't need one for my application because my waste travels uphill slightly (8" - 1') to the holding tank inlet.
I don't have a simple 1" hose lying around to test the intake with a bucket of water. I'll have to get creative to do that. Also, I was unable to get the 1.5" waste pipe loose from the toilet as well as the 1" inlet tube. I eneded up removing the plastic inlet tube connection from the diaphragm housing so that I could move the toilet 6" from the wall. So, my toilet is pretty limited in movement.
if you need the sanitation hose lowes carrys it. my hose was hard to get off till I heated the ends with a hair dryer then it came right off. when I put the new ones back on I put dish soap on the toilet ends and again used heat on the hose ends.