Coaches will replace trains on the Seymour and Shepparton lines for the entire journey until Sunday, May 8.
The trains are unable to run due to V/Line maintenance and infrastructure upgrades.
Coaches will replace trains between Southern Cross, Seymour, and Shepparton stations. Albury line trains will continue to run as normal during the dates.
Coach replacement services will be a mix of express, semi-express and stopping all stations.
V/Line coaches will not stop at Essendon station, so travellers will need to take a train replacement bus service to and from Broadmeadows to connect with V/Line coaches.
There will also be metropolitan distruptions on the Craigieburn line until May 6.
Commuters are advised to allow an additional 60 minutes for their journey.
V/Line also advises there is limited space for bikes on trains and coach replacement services; no pets or hot food/liquids are allowed on replacement coaches; customers require a valid myki or paper ticket to travel on all V/Line replacement coach services; and customers with accessibility needs should call 1800 800 007 before travelling.
In Melbourne, coaches will arrive and depart from the Southern Cross Station coach terminal located on Spencer Street, opposite Little Bourke Street.