Alan Johnson wrote:The former steel fuel tanks in my westsail 32 were never secured except for some bracing blocks around the base.  The fill and drain holes and pipe were all that stopped it from lifting. I have seen all thread used to hold down tanks in other westsails but my new aluminum tanks fit so well there appears no way to get behind with anything ridgid. I have currently a 1x6 clear  vert grain doug fir epoxied plank levered in and secured at the aft bulkhead. Is this sufficiant or is there another way.

On the early W32's Westsail used wood blocking between the top of the fuel tank and the underside of the deck.  That was later changed to stainless or aluminum straps bolted to the hullside, over the top and side of the tank, and using a threaded rod to a bracket fastened to the tank base.

The tanks should definitely be secured down.  When Mike Johnson took a rollover in his W32, one tank came off the shelf and landed on top of the engine.  He had a tough time emptying the diesel from the tank and saving it, before he was able to lever the tank back up on the shelf.

Of course, no one expects to do a rollover, but S**T happens.