I had a visit to Woods Dyke in Horning on Friday to Survey this popular little boat. This boat was designed by John Welsh. The medium to shallow V hull together with a long shallow keel allows for an easily handling cruiser.
Several other manufactures used Seamaster moulding to produce their own versions. This includes Ardvark Aird marine and latterly Bounty Boats. The hull is still used today by Viking 26 with their 26ft widebeam.
The factory built boat is unique in having through standing V berth configuration forward but with the shower toilet compartment extending across the width of the boat. A conventional dinette and galley area is further aft.
The craft also has a square foredeck to offer more space. This model has a particular emphasis on reducing production costs, over 400 of these boats were made.
The engine installation vary enormously from single petrol shaft drive to twin diesel. Some models had Volvo petrols with outdrive. This one had a single Perkins diesel on shaft.
Seamaster boats goes back to 1944 when Dick Sparrow(originally a cabinet maker)left London with his caravan, arriving to a field in Dunmow, Essex, which he eventually bought together with some ex W.D. tin sheds. These were used for Dick's original business, making toys, before going into caravan production. These models were called Vanmaster, and 250 caravans were built in total. In 1951, Vanmaster branched into a small boat production, introducing the Seamaster name. Up until 1960, the company was hugely successful, building some 200 craft between 17ft and 26ft.
Surveyors comments
Its becoming increasing common on my Surveys to see bilge pump outlets fitted through the hull very close to the water line. It must be high enough to remain above the water at the deepest angle of heel…see image above...or safer still stick a riser loop in it or a non return valve. Its one of the most common ways a boat sinks. Heres some tips on installing bilge pumps.
Mount the pump
You must not place the pump in the bilge unrestrained. If it falls over it will suck air and burn out. Pumps must be fastened down. Brackets are available that attach to a stringer or other vertical feature, or you can epoxy a couple of bolts to the bottom of the bilge to serve as mounting studs.
Float switches must also be fastened.
Use smooth-bore hose
Corrugated hose reduces pump output by as much as 30%, so always connect the pump to the discharge fitting with hose that has a smooth interior surface.
Bends and long runs also reduce pump output, so make the hose run as straight and as short as possible. That may mean discharging the pump through the side of the hull rather than through the transom. However. . .
Place the discharge above the waterline
If the discharge is submerged when the pump runs, the ocean siphons back through the pump into the bilge when the pump shuts off. When enough water has entered to float the switch, the pump will eject it, only to have it siphon back again. This continues until the battery is depleted, then the water floods the boat until it reaches a level that gets the crew's attention.
The discharge fitting must never go below the waterline. If the fitting is through the transom, be sure it is high enough not to submerge when the stern squats. And if it is through the side of the hull, it must be high enough to remain above the water at the deepest angle of heel.
Use a thin-wall fitting
The through-hull fitting can further reduce pump capacity. To minimize this restriction, use a fitting with the largest possible opening.
Lead wiring up
It is essential to get the pump wiring out of the bilge as quickly as possible. Run the wires up and secure them so that they do not sag into the bilge water.
Don't skimp on wire size
A 3,500 gph pump will draw 15 amps, typically necessitating 10-gauge, or maybe even 8-gauge wire. Consult the ABYC Wire Size Table to determine the appropriate wire for your pump and length of wire run.
Use butt connectors and heat shrink
Crimp-on step-down butt connectors will assure a good mechanical and electrical connection between the supply wires and the pump leads. Enclose these connections in adhesive heat shrink tubing to make them water tight. You must slide the heat shrink over the wire and out of the way before you make the connections. Then center the tubing over the crimped connector and shrink it with a heat gun or by playing a flame beneath it. Be sure there are no explosive fumes in the bilge!
Connect to the battery
When you turn the power off to leave the boat unattended, you don't want to turn off the bilge pump. Connect an automatic bilge pump directly to the battery, not through the distribution panel.
Fuse the positive side
It is essential to have a fuse in the positive wire as close to the battery as possible. Some switch panels (see below) include a fuse. Otherwise join an in-line fuse holder to the battery end of the positive wire using a crimp butt connector.
Install terminal fittings
Do not strip the ends of the supply wires and loop them beneath the battery terminal wing nuts. Install crimp-on ring terminals the proper size to fit the threaded posts on your battery. Use a copper washer-not steel-between the wing nut and the ring terminal.
Three-way switch
If your bilge pump has a separate float switch, you may want to wire it to a three way switch that allows you to select automatic, on, or off. Be sure to support all wire runs at least every 18 inches using cable clamps or ties.
Two pumps
A bilge pump big enough to deal with a real emergency will do a poor job of keeping the bilge dry because the water in the discharge hose drains back into the bilge when the pump shuts off. And a big pump requires a big hose.
The ideal bilge pump arrangement is a small (400 gph) automatic bilge pump mounted in the sump to dispense with rain and shaft-gland leakage, combined with a high capacity pump (3,500 gph) mounted higher to deal with more serious ingress.
Stepping the discharge hose from the small pump down to 1/2-inch minimizes the backflow from the hose when the pump cycles, maintaining a dryer bilge. The large pump can be wired to a float switch if you prefer, but I think a manual switch makes more sense. An added advantage of this bilge pump configuration is that the high-capacity pump sits high and dry, extending its life indefinitely.
Thinking of Buying a Boat and Need Help? Call Insight Marine Surveys Ltd. I specialise in Boats of all types, and I will assist you to make an informed decision. Contact me for a detailed and comprehensive report at: steventruss1@aol.com
Several other manufactures used Seamaster moulding to produce their own versions. This includes Ardvark Aird marine and latterly Bounty Boats. The hull is still used today by Viking 26 with their 26ft widebeam.
The factory built boat is unique in having through standing V berth configuration forward but with the shower toilet compartment extending across the width of the boat. A conventional dinette and galley area is further aft.
The craft also has a square foredeck to offer more space. This model has a particular emphasis on reducing production costs, over 400 of these boats were made.
The engine installation vary enormously from single petrol shaft drive to twin diesel. Some models had Volvo petrols with outdrive. This one had a single Perkins diesel on shaft.
 |
| The guys from Ferry Marine lifting her out for Survey. |
Seamaster boats goes back to 1944 when Dick Sparrow(originally a cabinet maker)left London with his caravan, arriving to a field in Dunmow, Essex, which he eventually bought together with some ex W.D. tin sheds. These were used for Dick's original business, making toys, before going into caravan production. These models were called Vanmaster, and 250 caravans were built in total. In 1951, Vanmaster branched into a small boat production, introducing the Seamaster name. Up until 1960, the company was hugely successful, building some 200 craft between 17ft and 26ft.
Surveyors comments
Its becoming increasing common on my Surveys to see bilge pump outlets fitted through the hull very close to the water line. It must be high enough to remain above the water at the deepest angle of heel…see image above...or safer still stick a riser loop in it or a non return valve. Its one of the most common ways a boat sinks. Heres some tips on installing bilge pumps.
Mount the pump
You must not place the pump in the bilge unrestrained. If it falls over it will suck air and burn out. Pumps must be fastened down. Brackets are available that attach to a stringer or other vertical feature, or you can epoxy a couple of bolts to the bottom of the bilge to serve as mounting studs.
Float switches must also be fastened.
Use smooth-bore hose
Corrugated hose reduces pump output by as much as 30%, so always connect the pump to the discharge fitting with hose that has a smooth interior surface.
Bends and long runs also reduce pump output, so make the hose run as straight and as short as possible. That may mean discharging the pump through the side of the hull rather than through the transom. However. . .
Place the discharge above the waterline
If the discharge is submerged when the pump runs, the ocean siphons back through the pump into the bilge when the pump shuts off. When enough water has entered to float the switch, the pump will eject it, only to have it siphon back again. This continues until the battery is depleted, then the water floods the boat until it reaches a level that gets the crew's attention.
The discharge fitting must never go below the waterline. If the fitting is through the transom, be sure it is high enough not to submerge when the stern squats. And if it is through the side of the hull, it must be high enough to remain above the water at the deepest angle of heel.
Use a thin-wall fitting
The through-hull fitting can further reduce pump capacity. To minimize this restriction, use a fitting with the largest possible opening.
Lead wiring up
It is essential to get the pump wiring out of the bilge as quickly as possible. Run the wires up and secure them so that they do not sag into the bilge water.
Don't skimp on wire size
A 3,500 gph pump will draw 15 amps, typically necessitating 10-gauge, or maybe even 8-gauge wire. Consult the ABYC Wire Size Table to determine the appropriate wire for your pump and length of wire run.
Use butt connectors and heat shrink
Crimp-on step-down butt connectors will assure a good mechanical and electrical connection between the supply wires and the pump leads. Enclose these connections in adhesive heat shrink tubing to make them water tight. You must slide the heat shrink over the wire and out of the way before you make the connections. Then center the tubing over the crimped connector and shrink it with a heat gun or by playing a flame beneath it. Be sure there are no explosive fumes in the bilge!
Connect to the battery
When you turn the power off to leave the boat unattended, you don't want to turn off the bilge pump. Connect an automatic bilge pump directly to the battery, not through the distribution panel.
Fuse the positive side
It is essential to have a fuse in the positive wire as close to the battery as possible. Some switch panels (see below) include a fuse. Otherwise join an in-line fuse holder to the battery end of the positive wire using a crimp butt connector.
Install terminal fittings
Do not strip the ends of the supply wires and loop them beneath the battery terminal wing nuts. Install crimp-on ring terminals the proper size to fit the threaded posts on your battery. Use a copper washer-not steel-between the wing nut and the ring terminal.
Three-way switch
If your bilge pump has a separate float switch, you may want to wire it to a three way switch that allows you to select automatic, on, or off. Be sure to support all wire runs at least every 18 inches using cable clamps or ties.
Two pumps
A bilge pump big enough to deal with a real emergency will do a poor job of keeping the bilge dry because the water in the discharge hose drains back into the bilge when the pump shuts off. And a big pump requires a big hose.
The ideal bilge pump arrangement is a small (400 gph) automatic bilge pump mounted in the sump to dispense with rain and shaft-gland leakage, combined with a high capacity pump (3,500 gph) mounted higher to deal with more serious ingress.
Stepping the discharge hose from the small pump down to 1/2-inch minimizes the backflow from the hose when the pump cycles, maintaining a dryer bilge. The large pump can be wired to a float switch if you prefer, but I think a manual switch makes more sense. An added advantage of this bilge pump configuration is that the high-capacity pump sits high and dry, extending its life indefinitely.
Thinking of Buying a Boat and Need Help? Call Insight Marine Surveys Ltd. I specialise in Boats of all types, and I will assist you to make an informed decision. Contact me for a detailed and comprehensive report at: steventruss1@aol.com
