Capt Frank Hopkins wrote:
This brings up another question. Could the pump out vacuum be causing the
tank to crack. It does "flex" when the unit is pumped out.

Since you've ruled out beating it to death, that's a good possibility,
'cuz strong repeated flexing can crack a tank...and the stronger the
pumpout, the more likely it is to happen, especially if the vent has any
blockage, even a filter in the vent line.


The pump in question is a diaphram type vacuum pump. I was seking a new
diaphram and duckbill valve set.

If the pump is the SeaLand S-series vacuum pump, You can get parts for
it directly from SeaLand--800-321-9886. Duckbills and bellows aren't
available as a set. Duckbills were about $8.50/each last time I saw a
price list--which has been a while, so they may have gone up...the
bellows (diaphragm) was a whopping $90. Are you sure you need one?? 'Cuz
bellows failure is VERY rare. What are the symptoms? If you don't have
a VacuFlush manual, I strongly recommend you ask for one when you order
the duckbills, 'cuz just about every possible symptom, probably causes
and cures are included in it. The current manual is fine no matter what
the age of your toilet...the V/Flush hasn't changed enough to notice in
more than 20 years.


I would appreciate any recommendations for heavier walled tanks then the
Todd units. I am getting a little thin on scrubbing sewage out of the engine
room.

Can't blame you for feeling that way! Your best source for a tank is
Ronco Plastics...they make TOP quality thick-walled (at least 3/8")
tanks for a very reasonable price and have more than 400 shapes and
sizes to choose from, including over 100 that are non-rectangular. Their
catalog is on their website at http://www.ronco-plastics.com

Would re-piping the system with PVC pipe, eliminating the hoses, be any
advantage other then making the engine room a little neater? The hoses take
up an inordinate amount of room. The fellow who installed the vac-u-flush
system was not real slick as far as a clean installation.

Unless the hoses have permeated, I don't think you'll gain enough to
make it worth the effort. Hard pipe is only recommended for long
straight runs, and has to be soft-coupled to anything rigid--toilet,
tank, thru-hull, pump etc--with enough hose to provide shock absorption
and protection from flex, so you prob'ly wouldn't gain very much.
If/when your hoses start to stink and require replacement, it might be
worth considering, but not till then.

--
Peggie
----------
Peggie Hall
Specializing in marine sanitation since 1987
Author "Get Rid of Boat Odors - A Guide To Marine Sanitation Systems and
Other Sources of Aggravation and Odor"
http://www.seaworthy.com/html/get_ri...oat_odors.html