Aft Water Tank/Steering Problem...

[Tom P, IMPULSE #233, '86]

After removing the pedestal/steering access cover in the aft cabin this weekend (the fiberglass cover on the aft bulkhead which allows access to the bottom of the pedestal), I made an interesting and disturbing discovery...

The aft fresh water tank has changed shape, and is rubbing on the quadrant and one steering cable...More precisely, the water tank has a 90 degree step molded in the top edge of the tank to allow for steering mechanism clearance, but part of this 90 degree step has "inverted", and is now sticking up and touching/rubbing the quadrant/steering cable...

The tank appears to be made from fairly thin plastic/poly, and seems to change shape easily with pressure put on it (by prying with a hammer handle)...Unfortunely, there just isn't enough room for me to get good leverage, or enough travel to "pop" the tank back to the correct shape...

Has anyone experienced the same???

If so, were you able to pop the tank back into shape, or did you have to replace it???

I'm planning on first filling the tank with water to see if the weight of the water will help pull it back into shape (not too optimistic about this working), and my second move is just removing the tank (assuming it will come out througt the aft cabin) and seeing if I can reshape the tank, and hopefully it will retain the correct shape...  

I rarely keep water in my tanks (maybe twice in 2 yrs, for a week at the time), and nothing heavy is stored in the aft cockpit locker (only life-jackets and fenders)...Although, the previous owner did store the inflatable dink there...But I know I've looked here before and did not have any problems...

Weird!

Tom P.

[Ken Juul]

Since you don't use your tank much perhaps the vent tube has been blocked by insects building a nest.  The tank may be collapsing because of an internal vacuum.  Try opening the fill cap and see if anything changes.  Unless it has a defect the tank should maintain shape.

[Tom P, IMPULSE #233, '86]

Ken/Vicki,

Thanks for the thought, but I don't beleive the fill or vent is the problem...I opened the water fill, and nothing happened...I even disconnected the fill hose at the tank, no pressure present and no changes to the tank...

To help clarify, it would have taken excessive water tank pressure (not a vaccuum) to push the L-shape in the tank edge outward...And I beleive that would be very difficult to do with a tank that stays dry 98% of the time...

The only thing I can figure is that at some point when there was water in the tank, heavy seas may have caused the water to slosh around in the tank, then causing tank to "pop" the L-shape outwards...I'm sure the tank has no baffles, and a heavy sea could easily start a destructive wave inside the tank...

The aft tank is quite flimsy...

Just my theory...

Thanks anyway though...

Tom P

[Ted Pounds]

Tom,

If you don't use the tanks much how about pulling the aft tank out permanently.  Then convert the area for more storage.  You'd still have the starboard tank when you need to store some water.  Just a thought...

Ted

[Ken Juul]

Ron may have provided the answer.  Perhaps it is a non catalina retrofit that isn't as sturdy as it should be.