Jerry, I just finished my '10 3670 and the whole process takes about 20-25 minutes. There are several threads that outline general winter prep, but I will outline what I did:
- I made sure all other house keeping chores were finished and the antifreeze process was the last thing I would do prior to closing it up. For example make sure all tanks, holding and fresh water, are drained, potty clean, shower clean, etc. Finish all tasks that might require water.
- At this point the water pump should be turned off.
- Open any hot water valve to relieve pressure on the water heater.
- At the water heater; turn off electric switch (black toggle switch) and insert the locking pin through the hole provided in the switch. This , of course, prevents turning on the electric heating element I keep my locking pin attached on one of the wires when not inserted in the switch. It help keep the pin from becoming lost.
- Remove the access panel on the water heater and remove the Anode Rod ( 1 1/16" socket) from the water heater and allow to drain.
- Move valves in the UDC to "Winterize" and extend the hose provided for slurping up the pink antifreeze. Insert the hose into the pink stuff container.
- I had my wife observe the level on the pink stuff during this entire process so that we didn't suck up air into the water system.
- Turn on the water pump and let the system charge. The pump will shut off when charged.
- A good place to start is the outside shower, since you can observe the process of sucking from the pink stuff container. Using a bucket to capture water and pink stuff, turn on the cold water valve on the outside shower until the water is replaced by the pink stuff. Turn on the hot water valve until the water is replaced by the pink stuff.
- Move into the coach and connect a short line of hose to the cold water faucet of the washer dryer hookup. Again, using the bucket, open the cold water valve until the water is replaced by the pink stuff. Repeat for the process for the hot water valve.
- Remove the cap on the washer drain and pour in some of the pink stuff. Your estimate as to how much is as good as mine.
- Move to the potty and flush until the water is replaced by the pink stuff.
- I used the bucket to capture fluid in the shower. Again, turn on the cold water until the water is replaced by the pink stuff. Likewise for the hot water valve.
- Pour some pink stuff down the shower drain.
- Now the bathroom sink. You guessed it, open cold valve until water is replaced by the pink stuff. Likewise for the hot water valve.
- Pour some pink stuff down the bathroom sink drain.
- Moving to the kitchen, you're now getting the hang of it! Same process as the bathroom sink.
- Finally, move back to the UDC and address your attention to the holding tank flush. There are at least two options here. One is to blow out the line using 40-50 psi through a Schrader valve to 3/4" male adapter. Another is to buy a pump such as:
http://www.campingworld.com/shopping/item/plastic-winterizing-hand-pump-kit/4411 Or, I heard of one method where you buy a 1/2" to 3/4" male-to-male adapter and plug the shower head hose (remove the shower head first, of course) into the input of the sprayer and run pink stuff by opening a valve at the outside shower. The latter is a quick method, but you know the risk.
- Throughout all this process be sure you monitor the level of the pink stuff.
- I don't think I forgot anything, but no guarantee! Good luck!