The filter is going to have an in and an out fitting on each side. Make sure you are connected to the appropriate one. If it runs OK without the bulb, those connections are OK. Make sure the bulb isn't reversed. If you are sure the hoses are correctly connected, squeeze the bulb with your finger over the suction side. You should feel it sucking on your finger. You should also feel air blowing out the other side. If you don't, you could have a bad bulb.
2015 Seaark 1872 MV CC Etec-90
Helix 12 CHIRP SI, HB 1199, MinnKota Riptide ST80/i-pilot Link, Bob's Hydraulic
Bitter Gun Owner