Trainer Darren Weir has celebrated his 48th birthday by training four winners on the second day of Warrnambool's three-day May carnival.

It followed a quartet of winners on the opening day on Tuesday.

Weir opened his account on Wednesday with $6.50 chance Truly High before favourites Big Bad Baz ($1.55), Handsome Thief ($2.90) and Lucky For You ($1.95) all saluted.

On the middle day of last year's carnival Weir won five of the 10 races on his way to a carnival record of 14 winners.

Weir has 23 runners down to run on the final day across the 10 races as he attempts to close in on last year's record.

Surprisingly Weir is yet to train a winner over jumps at this year's carnival.

He has Duke Of Boneo down to run in the Novice Hurdle and Now And Zen in the Grand Annual Steeplechase.

Chasing a fifth successive Warrnambool Cup, Weir will be represented by 2016 winner Master Of Arts, Gallic Chieftain, Kiwia and Yogi.