Improving the Water Tanks

The stainless steel tanks on our tugs were made with an aluminum hatch. To recap our previous discussions on the problem of these two dissimilar metals [see 2014 TUGGERS, Issue 58, page 5]:

"...when the dissimilar metals of the aluminum lids and the stainless steel water tanks are exposed to relatively high pH water (+8), aluminum hydroxide will form. The aluminum hydroxide manifests itself in two rather unpleasant ways: as a clear gelatinous precipitate on the lid; in myriad gray/green granules on the tanks bottom."

Some owners have replaced the aluminum lids with plastic deck plates. Another option is one Fred Nusbickel, Georgia J. 37VT65, implemented. He simply put insulating gaskets between the dissimilar metals (red arrow in photo). Since adding the gaskets, Fred said he no longer gets the aluminum hydroxide in his tanks. The biggest problem with the job was getting the original bolts loosened.