Mobetah in St. Pete Beach Florida just prior to leaving for the Northwestern Caribbean

Mobetah in St. Pete Beach Florida just prior to leaving for the Northwestern Caribbean

About Us

Until his retirement, Bill Was a Landscape Architect for the National Park Service and Pat was a Physical Therapist.

Thursday, August 28, 2008

Rebuilding The Watermaker

When we first built the watermaker, several years ago, we used a 1 1/2hp electric motor, a 2 gpm high pressure pump and a 21" membrane. The system worked well and produced about 10 gph of pure fresh water. Had we used a 40" membrane the system probably could have produced about 16gph or had we used a smaller motor and smaller high pressure pump the system would have produced less water however, it could have operated using our inverter. We had to remove the watermaker while replacing the leaking fuel tank so we decided to rebuild it using a smaller motor and high pressure pump while it was out.

While the fuel tank was being replaced, we have managed to purchase a new Baldar 1/3hp motor (explosion proof) for $109.00 and a stainless steel Cat pump (SF05SEEL) for $125.50 (both were purchased off ebay). The specifications for the new system (motor, high pressure pump and membrane) should be very similar to HRO's Seafari mini 170 system and produce about 7 gph.

We had new high pressure hoses fabricated by the local Motion Industries and have now reinstalled the watermaker into the boat.
In addition, we will install a new 21" filmtec membrane just before we leave on our next cruise.

Sunday, August 24, 2008

The MOBETAH Fuel Tank Story

Our boat, Mobetah, has been at the Demopolis Yacht Basin for two years now. A little over a year ago we discovered that we had the dreaded Endeavour fuel tank leak. It required a year (for various reasons) to replace the fuel tank and aft water tank.

Bill modified the fuel tank design. As a result our fuel tankage was increased from 75 gallons to 110 gallons. The down side of having more fuel storage was that the aft water tank storage was decreased from about 80 gallons to 33 gallons. Not to worry that still leaves us with 132 gallons of water tankage.

The old fuel tank and aft water tank were set in 1/2 inch of polyester resin and foamed in place. This allowed salt water to soak into the foam next to the tanks with no way to ever pump it out.

The new tanks were manufactured by Ezell Tanks and we recommend them highly ( http://www.ezellindustries.com/ ). After the old tanks, generator and various other pieces of equipment were removed, the new fuel tank was once again set in epoxy resin and foamed in place (with high density foam) to within about four inches of the top. This time however, epoxy resin was poured around the tank up to within about 1 inch of the top then a fiberglass mat and epoxy resin was used to seal the top of the tank and foamed/epoxied area and connect it to the fiberglass hull. This prevents water from entering the keel area and because of the new fuel tank design has a sump area so the bilge pump can drain the bilge area completely. The new aft water tank is basically a saddle tank, above and across the forward end of the new tank.

Now that the new fuel tanks, along with the generator and other equipment, have been installed, all appears to be working well. So now we'll rebuild our homemade watermaker (which is now sitting in Bonnie's garage) and Bill will make a few trips over to the boat to try and catch up on all the routine maintenance items that have been neglected for the past year and a half.