T&T: VacuFlush issue

[Elliott Bray]

I have been band-aiding a Vacuflush issue for several years and decided it
was time to fix it.
I have the type where pump sits on top of the 'L' shaped vacuum tank.

A little Background:
The 1 1/2" sanitary hose from the toliet connects to one end a somewhat
specially built PVC elbow.
The other end goes through a rubber (?) gland called a 'UniSeal' and
supposedly makes an airtight seal.

I disconnected the hose from the toliet, inserted the Sealand vacumn gauge,
and ran the system.
The system would not reash the cut-off point until I put sideways pressure
on the elbo at which time I could get 11" Hg and the pump shut off.
Releasing my pressure allowed air in and started the pump.

More background: I had suspected this junction was my problem. MY 'band-aid'
was to keep it coated with a thick Lithium grease but that solution causes
other problems. OBTW I have already replaced the duckbill valves.

My more permanent solution and the reason for my query.....
I am going to put a bead of something around the elbow end going into the
Uniseal and permanently 'glue' the elbow to the uniseal. I'll cut it out if
I have to replace it later.
I can think of several and would like help choosing..
[] 3M 5200
[] 3M 4200 or other 3M product
[] some Permitex product
[] Life Caulk
[] Something else

I get the Digest but since I am going to fix this today please respond
directly to me.
I'll let the list know what I do.
TIA

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Elliott Bray
M/V Letitia - Gulfstar 44 MC
www.loopcruiser.com
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