It's anything but smooth sailing on the Salish Sea for BC Ferries.

Mechanical problems have resulted in more cancellations on the Swartz Bay to Tsawwassen route Wednesday.

"Due to a mechanical difficulty with the main engine91ÂãÁÄÊÓƵ™s propulsion system on the 60-year-old Queen of New Westminster, the following sailings between Swartz Bay (Victoria) 91ÂãÁÄÊÓƵ“ Tsawwassen (Vancouver) have been cancelled," according to a BC Ferries advisory.

Wednesday will see the noon and 4 p.m. sailings cancelled out of Swartz Bay and the 10 a.m. and 2 p.m. sailings from Tsawwassen. The mechanical issues resulted in a number of sailings being cancelled Tuesday, with more cancellations expected through Sunday.

Thursday cancellations include the 8 a.m., noon and 4 p.m. sailings out of Swartz Bay as well as sailings departing Tsawwassen at 6 a.m., 10 a.m. and 2 p.m.

"If you have a booking on one of these cancelled sailings, you will hear from our Customer Service Centre who will let you know if we can fit you on an alternate sailing later today, or if your booking must be cancelled. In the case of a cancellation, we will refund your fees and/or fares," according to BC Ferries. "We appreciate your patience and apologize for any inconvenience you may experience as a result of these cancellations."