I am in the process of replacing my manual jabsco with a wilcox crittenden electric head, it did not come with a solinoid for the vent loop is this something that is needed, also it does not draw the water unless vent is completely shut off any ideas on this. BTW if any 356 owners are considering this project make sure you order the 90 deg discharge outlet with toilet, also I tried the jabsco electric but sent it back FYI. thanks in advance JohnS/V Alcyone356 #202