when I went to flush and replace the coolant on the westerbeke 30b in my 2001 Gemini 105mc the drain plug was frozen solid. It seems someone had replaced the brass plug with a steel plug which was not coming out. So after consulting the web, the owners manual and the stars, I came up with this work-around. Apparently if you still have your domestic water heater or cabin heater connected you can tap into that loop, but mine had been disconnected by the PO. in any case here are the steps I used. I AM NOT SUGGESTING ANYONE FOLLOW THESE STEPS, I AM NOT A DIESEL MECHANIC OR EXPERT OF ANY KIND. THIS IS SIMPLY WHAT I DID. IT WORKED FOR ME. YOUR RESULTS MAY DIFFER on your westerbeke 30b
Flush westerbeke 30b with frozen drain plug
- Find a place to tap in. to the coolant loop of your westerbeke 30b or other enine I took out the hose between the heat exchanger and the header or manifold (not sure of the name).
- Get what adapters you need to feed a garden hose into one side (heat exchanger side in my case) and a drain on the other end.
- Remove the thermostat – MAYBE this does not need to be done as there is a bypass circuit on the westerbeke 30b. You may want to try it without removing the thermostat. but if water does not flow well enough, this may be a step you want to take.
- Turn hose on AT LOW PRESSURE, and drain sludge into a bucket. Continue until you have clean water coming out.
- Fill bucket with distilled water and replace garden hose with distilled water pumped from the bucket via small pump.
- Fill bucket with 100% anti freeze and pump this through until you start seeing antifreeze come through.
- Replace the thermostat using a gasket-maker (after cleaning the mating surfaces), let it set as directed, then torque down
