Do yourself a favor and buy an outboard motor flushing tank, cheap and holds five gallons of antifreeze with an on/off valve. Throw a towel on top of the compartment door and set the tank on the door. No leaks and do the whole RV without having to run outside and change bottles!!
I tried winterizing but the pump wont draw the antifreeze up. I have a 2019 377fl highcountry. I put my hose into the winterization connection the other end in the jug. I turned on the pump but it wont draw it up. Do I need to pump it in with some sort of pump thru the city water connection.
I've had success with hooking a hose to the inlet and pressuring the system with water and turning the pump on and then off. This primes the system. Then disconnect hose and setup the anti freeze bottle and hose and turn on pump. Pump will take antifreeze easily. Haven't tried turning the cone washer around but will give that a try next time.
2016 Montana HC 305RL
2013 GMC 3500HD Denali SRW