ZZ13
Well-Known Member
This was my first I/O winterization. I spent the last 2 months reading everyone's home remedies and such. After much consternation I decided just to follow the manuals. Here's what my 300DA manuals say to do. Bold text is additional stuff I added in, not called out in the manuals. Maybe this will help other newbies. Sorry about the font size changes.
A/C System: Close seacock. Disconnect hose at A/C water pump and allow to drain (it is lowest point in system). Reconnect hose. (Additionally: Blow out through that hose with shop vac for good measure. Vacuum out water from strainer to seacock). Ensure a/c condensate drain line is not clogged to prevent drainage into shower sump.
Water System (flush method): Turn on water pump and pump out all water from tank. Bypass hot water heater. Fill water tank with sufficient anti-freeze to flush all lines or disconnect water pump supply hose and connect open hose to pull antifreeze from anti-freeze jug. Turn on water pump and open/close every faucet (hot and cold) one at a time until pink antifreeze comes out of each. Include toilet water supply. Reattach water pump supply hose from tank. Turn on water pump and pump out all faucets (I did not do this step). Open hot water heater drain valve and drain all water. Pump out holding tank. Flush one gallon of antifreeze through toilet vacu-flush. Pump out holding tank. Ensure shower drain line is not clogged to prevent drainage into shower sump. Pour antifreeze in sump and pump out
Generator: Change spark plugs, zinc, impeller, fuel filter (if needed). Run engine until warm. Change oil/filter. Close seacock. Remove hose at seacock and put in bucket with 2 gallons of nontoxic antifreeze. Run generator until most all antifreeze is pulled through cooling system. Turn off generator just before bucket is empty. Re-attach hose to seacock (leave seacock closed).
Engines: If E0 fuel, fill tanks with stabilizer added. If E10 fuel, empty tanks as low as possible and add stabilizer. Flush fresh water through engine. Run engine to warm oil. Change oil/filter. Connect 6 gal of fogging mixture to fuel system and run at 1300rpm for 5 minutes. Restore original fuel connection. Drain water from engine using your engines drain system (3-pt drain plugs on my 350Mag). Replace drain plugs. Fill engine cooling jackets with propylene glycol anti-freeze via hoses at thermostat. Replace water separator fuel filter.
Note: I had the Sea Ray dealer do the engines. They filled the tanks with stabilizer to 7/8 full even though it was E10. They also filled the cooling jackets via the bucket method rather than through the t-stat hoses.
A/C System: Close seacock. Disconnect hose at A/C water pump and allow to drain (it is lowest point in system). Reconnect hose. (Additionally: Blow out through that hose with shop vac for good measure. Vacuum out water from strainer to seacock). Ensure a/c condensate drain line is not clogged to prevent drainage into shower sump.
Water System (flush method): Turn on water pump and pump out all water from tank. Bypass hot water heater. Fill water tank with sufficient anti-freeze to flush all lines or disconnect water pump supply hose and connect open hose to pull antifreeze from anti-freeze jug. Turn on water pump and open/close every faucet (hot and cold) one at a time until pink antifreeze comes out of each. Include toilet water supply. Reattach water pump supply hose from tank. Turn on water pump and pump out all faucets (I did not do this step). Open hot water heater drain valve and drain all water. Pump out holding tank. Flush one gallon of antifreeze through toilet vacu-flush. Pump out holding tank. Ensure shower drain line is not clogged to prevent drainage into shower sump. Pour antifreeze in sump and pump out
Generator: Change spark plugs, zinc, impeller, fuel filter (if needed). Run engine until warm. Change oil/filter. Close seacock. Remove hose at seacock and put in bucket with 2 gallons of nontoxic antifreeze. Run generator until most all antifreeze is pulled through cooling system. Turn off generator just before bucket is empty. Re-attach hose to seacock (leave seacock closed).
Engines: If E0 fuel, fill tanks with stabilizer added. If E10 fuel, empty tanks as low as possible and add stabilizer. Flush fresh water through engine. Run engine to warm oil. Change oil/filter. Connect 6 gal of fogging mixture to fuel system and run at 1300rpm for 5 minutes. Restore original fuel connection. Drain water from engine using your engines drain system (3-pt drain plugs on my 350Mag). Replace drain plugs. Fill engine cooling jackets with propylene glycol anti-freeze via hoses at thermostat. Replace water separator fuel filter.
Note: I had the Sea Ray dealer do the engines. They filled the tanks with stabilizer to 7/8 full even though it was E10. They also filled the cooling jackets via the bucket method rather than through the t-stat hoses.
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