The mountain road is due to close this morning (6 April) for a week of repairs ahead of TT.
The stretch between Creg-ny-Baa and Ramsey Hairpin will be closed 24 hours a day (from 8am) until 6pm next Sunday, 12 April.
Work teams will carry out a range of repairs including road lining, ditching, erection of one way TT signage and sign maintenance.
The improvements include a re-profiling of the road on the Keppel Gate section of the course.
The Department of Infrastructure says the full closure should mean essential pre TT works are completed in one go, without the need for further disruption.
Minister Phil Gawne says all Manx motorists will benefit from the upgrade and is thanking people for their patience and cooperation.