Volunteers at the charity have launched a crowdfunding appeal to reach as many people as possible to buy a replacement.
The tractor, now at the end of its working life, is used to tow the centre's safety boats from the AYAC Jubilee Compound to the waterline and back up the beach at the end of each sailing session.
Without a tractor the one-tonne powerboats used to provide critical safety support for the children sailing off the coast cannot provide the cover necessary.
Centre chair Jason Brockhurst, said: "We've nursed the tractor for many years but it isn't going to last much longer. "We desperately need a safe and reliable tractor to enable us to keep our young sailors safe and deliver the sessions we dearly want to."
AYAC was formed in 1977 to provide sailing opportunities for children who may not otherwise have the chance to experience the sport, despite living in a seaside town.
Most children who attend the centre for Sunday morning and Wednesday evening sessions come from the town. The centre is an RYA Recognised Training Centre, introducing and teaching young sailors from eight to 18.
Volunteer Andy Wilson, from Littlehampton, who set up the fund, added: "After many years of service the tractor has to retire due to the exposure to sea water. Any donation however large or small will help us to continue to make a difference to children's lives."
.......about the centre
With thanks to Yachts and Yachting for letting us reproduce this story.