Winterizing Sea Dragon



Winter in our area means a couple of snows and 3 months of below freezing weather at night. Winterization includes hauling, winterizing the fresh water system, and winterizing the engine. We haul Sea Dragon during the first  week of December and launch in mid to late March. This way we are on the hard only about 4 months each year.

The list of winterizing activities include:

  1. Drain the water tanks
  2. Drain the water lines
  3. Drain the water heater
  4. Drain & flush holding tank
  5. Winterize the head
  6. Winterize the Air Conditioner
  7. Change Engine Oil
  8. Change V-drive Oil
  9. Replace all fuel filters
  10. Top off fuel tank
  11. Stabilize fuel
  12. Fog engine
  13. Flush raw water system  (Engine)

Over the years I have tried several approaches to winterize the fresh water system. I have never liked the idea of filling the lines with the "pink" fresh water anti-freeze. It leaves a strange taste / smell in the system and stains everything.

I also learned, the hard way, if I wait too long to drain the system it will freeze. The fresh water lines that run along the hull and deck above the water line and near the mixer for the shower is susceptible to freezing and breaking if we have several days of 20 something degree weather.

So I usually winterize the fresh water system, head and air conditioner in early November and the engine in late November or early December just before hauling


Sea Dragon's Fresh Water System

        The first step is to drain the fresh water tanks. To do this I remove the charcoal filter (throw it away), drain the container, empty and clean the strainer. Next I drain the hot water heater.
To drain the hot water heater, I simply remove the drain plug located with the cold water inlet, then open the pressure relief valve.  The water can be drained into a bucket and dump it overboard.
Next the output line is removed from the filter and using plastic fittings and increasing diameter hose(s), I connect the line to output side of the foot pump for our Avon dinghy.

Once the connected, I can place the pump just outside the companion way. Then beginning with the sink in the head, I open the cold water facet and pump air through the system until only air comes out... It is easy to hear the water or air being force out the facet while standing in the companion way..

I close the sink facet and repeat the process for the shower and then the galley sink.

Then repeat the same process for the hot water lines.

Next comes the head. In this case I do use the "Pink Fresh Water Anti-freeze".

I begin by closing the seacock to the Head. Next the line feeding the AC is removed and a short piece of hose is connected and placed in a gallon bottle of anti-freeze. Then I operate the head until a full gallon has been pumped through the system.

See "I am an Idiot - a Failed Winterization" to better understand the importance of this step.

This process is repeated for the Air Conditioner.


Next comes the task of changing the Fuel Filter and Bleeding the big Red Beast


I begin by collecting the necessary tools and parts.

- 5/8 open end & Box end wrench
- 5/16 inch open end & box end wrench
- 2 large zip lock bags (1 gallon)
- Roll of paper towels
- New fuel filter (Fram C119)

Replacing the fuel secondary filter can be a messy process on Sea Dragon but it is scheduled for replacement every 50 hour of usage or each season. So it must be done.

The first step is to take a large zip lock bag (the stiff top makes it easier to work around the filter) put a wad of paper towels in the bottom of the bag then slip it around the filter.

Next remove bolt #3 and drop the filter and base into the bag. The paper towels will prevent the fuel from spilling out of the bag.

Remove the base #9, seal the bag, and dispose of properly.

Replacing the Secondary Filter

Begin by drying and cleaning the base, the O-ring seat in the base (#9) and the top (#2) O-ring seat. Next re-assemble the secondary filter noting that the LARGER O-ring should be placed in the top (#2).

Finally, the fuel system must be bled... This can be a messy job if care is not taken.

The bleeding process is outlined below.

There are four basic steps plus one optional step. Each is detailed below.

1. Bleed fuel line from Racor to secondary filter

2. Bleed secondary filter

3. Bleed fuel injector pump

4. Bleed high pressure lines

5. Cross fingers (hope you did right the first time)

Start engine.

   Begin by placing a wad of paper towels in the second zip lock bag and placing it around the fuel filter as high as possible. This time the bag should fit loosely and as high as possible on the filter. This will catch the large amount of fuel that will be pumped from the filter.

First bleed the air from the portion of the fuel line from the Racor to the secondary filter. To do this, pump the lift pump for approx 1 minute. Note: move the pump lever up and down using slow, smooth full strokes at the rate of one stroke per second.

Next, bleed the air from the new filter by first loosing the banjo bolt shown at the right. Using the pump lever, pump until the filter is free of all air. This takes some time, so pump until NO AIR bubbles can be seen.. I am always surprised how much fuel will be pumped into the catch bag.

Once the air is expelled tighten the banjo bolt, remove the bag, seal, and dispose of properly.

Note Bleed point 1 on Sea Dragon is located on the fuel pressure sensor (see small picture above)

Now the fuel injector pump must be bled. I begin with a hand full of paper towels

Beginning with bleed point #1, open the 5/16 inch bleed point (a needle valve). Place the wad of paper towels around the open bleed point. Once again, I surprised how much and how far the fuel will spray if not stopped by the towels.

Once again with steak slow strokes, bleed all air from point #1 (don't fooled by the first signs of fuel, PUMP until NO AIR comes out).

Close the Bleed point #1, CAUTION use care the bleed assembly is easily broken (see below).

Now, open Bleed Point #2 and repeat the bleeding process. This step always takes longer than I expect, so do not be fooled by the first sign of fuel.. Do it right.

Take your time!!!! Be Careful!

Westerbeke used two different bleed screw assemblies on the W40. The broken one on the left has threads of 1/4 inch by 28 and is the most difficult to find if a replacement is needed. And the one on the right is 3/8 by 28 thread and is the most common.

Oh by the way.... $30.00



In case of an emergency I found an
allen screw that matches the thread size.
I have cut the screw to length and I keep it in my spare parts kits as a backup.

Above you can see the assembly and how it works

Back to bleeding the engine.

Now with all fuel wiped up, it is time for the final step.

Loosen the high pressure lines leading to ALL four injectors... Do NOT remove ONLY about 1 or 2 turns. Place the paper towels around each open injector nut.

With the throttle in full open, use the starter to crank the engine until fuel spurts from each injector high pressure lines.

I place white paper towels around each loose nut and check for signs of fuel on the towel... The red dye in the marine fuel is easy to see from the companion way.

CAUTION: DO NOT crank the engine for long periods of time. Excessive cranking will cause the starter to over heat and will fill the exhaust with sea water.

Next retighten each of the four high pressure lines.

With the throttle still in the full open - start the engine normally.. Several attempts may be needed... take your time.


Next -- after the engine has run for several minutes and reached operating temperature I change the Oil. The process begins with removing the old oil. I use the Moeller vacuum pump which works better than anything else I have found.

  Steps are:
             1. Remove the dip stick
             2. Insert the plastic tube into the dip stick tube until it just touches the bottom
             3. Seal the opening with the plastic cover that best fits the dip stick tube
             4. Loosen the oil fill cap
             5. Pump the vacuum pump several times and walk away

The Moeller system will remove the oil in 3 or 4 minutes.

During this time I can do other things, replace the oil filter.
While the oil is being sucked from the engine, it is time to change the filter. Sea Dragon has remote filter located just inside the engine compartment so this task is much easier than if the filter were attached to the engine.

Over the years I have become tired of cleaning up the oil drips and spills when removing the filter. I take a large zip lock bag, put several paper towels in the bottom, and slip it over the filter. I unscrew the filter, let it drop to the bottom of the bag, and then wait for the oil to drip/run into the bag (note my high tech wire hanger).

Once I feel most of the oil has dripped into the bag, I zip the top and screw another filter on --- and of course dispose of the filter and oil the in proper fashion.

And finally, refill the engine with oil, restart the engine, let it run so the fresh oil circulates through the engine and fill the filter... Finally, check the oil level and my winterizing task are almost complete.
Once the engine has run for about 10 minutes, I close the seacock for the sea water intake. Then open the strainer, remove the basket, start the engine and pour anti-freeze in until it comes out of the exhaust... Shut down and the engine is ready for a winter alone.
One of the final step is to pour "pink antifreeze" into the bilge and sump shower/sink sump pump. Then pump the antifreeze out so that no water is left in the lines.

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Copyright 2006 Garner Bennett. All Rights Reserved