The project to replace more than three miles (4.8km) of track is scheduled to be completed before the service reopens next Easter.
RMS Locate will undertake work such as dismantling and reinstalling rail sleepers and installing new drains.
The scheme includes the priority sections of Douglas to Laxey and Laxey to Ramsey.
What are these?
Most Popular Now | 44,871 people are reading stories on the site right now.";