T&T: SeaLand Vacu System

[rednax at travel-net.com]

Have been following the discussion on having a vacu flush BW system; 
however, have a fwd and aft system on our boat.  Have instituted Peggy's 
recommendation to flush the system once a week with a couple of bowls of 
water.

My problem is the fwd system is cycling, the aft system does not.  The work 
I've done has been over a 7 week period so that I could assess each repair 
on its own.

The system was installed 17 years ago.  First I replaced the ball and shaft 
on the fwd head (no change), replaced the duck bills in both vacuum pumps 
(no change), the bellows in the forward vacuum pump (heard a hissing coming 
from it - no change), and replaced the fwd BW hose from the toilet to the 
vacuum tank (there was some minor cracking of the hose and when twisted did 
make the vacuum pump come on - cycling reduced to about once an hour).  
Vector marine in Sidney is stumped as am I.  

I also took the hose off the vacuum tank and plugged the tank inlet.  Still 
cycled a bit but I thought it might be a loose seal only.  I do not expect 
the vacuum tank to be damaged.

Two thoughts, replace the small hose between the vacuum tank and the pump, 
approx 5 inches, then do a remove and reinstall of the ball and shaft on 
the forward toilet, maybe it did not seat properly.

Any thoughts?

Thanks in advance.

Ernest Nash
40 Ft Bayliner Bodega
Victoria BC