* Harbor gasoline rises 4.50 cts/gal on hydrotreater fire * Harbor distillates remain strong * Midwest ULSD firms on agricultural demand NEW YORK, March 19 (Reuters) - The New York Harbor gasoline market received a boost on Monday with differentials for March supplies rising sharply after a fire on Friday at PBF Energy's 182,000 barrels-per-day Delaware City, Delaware, refinery. The fire in a desulfurization unit, also known as a hydrotreater, was extinguished after less than an hour late Friday, PBF said. The company declined to comment on operations but an industry source said one of fou r hy drotreaters at the plant remained shut. Regional gasoline trade was lifted by the news, with any-March F4 RBOB done at 19.25, 19.00, 18.50, 18.25 and 18.00 cents per gallon under the April RBOB futures contract on the New York Mercantile Exchange, up 4.50 cents from Friday's settlement. Prompt F4 RBOB was done at 19.00 cents under, up 2.50 cents from Friday. Prompt M4 conventional gasoline was done at 17.00 cents under, up 4.00 cents. Harbor distillate markets marched higher, with prompt ultra-low sulfur diesel still garnering much of the trade's attention, and traded at 8.00 cents over the April heating oil futures contract on NYMEX for a barge load, up 0.50 cent. Pipeline ULSD was heard done 7.50 cents over. Traders have been scrambling to make sure they have their ULSD needs were covered ahead of an April 15 deadline from Buckeye Partners LP to switch all of its pipelines and terminals to lower-than-15-parts per million heating oil. In the Midwest, Chicago ULSD lost ground in afternoon trading and fell about 7.50 cents as a major trade house sold more supply into the market, traders said. Chicago ULSD was seen at 17.50 cents under April heating oil futures contract, the traders added. Meanwhile, Group Three ULSD rose 1.50 cents to 2.00/2.50 cents over on seasonal agricultural demand as the planting season approaches. Warm weather this winter has created an ideal environment for early corn planting in the U.S. Corn Belt. On the Gulf Coast, M2 conventional gasoline gained 3.50 cents 14.25 cents under after Valero Energy Corp announced it would shutter its 235,000 bpd refinery in Aruba by the end of March because of poor margins. The refinery had already shut in 2009 for 17 months because of poor economics, and restarted in early 2011. The plant had processed heavy sour crude oil into gasoline, heating oil and feedstock components to make finished fuel to the U.S. Gulf Coast, the New York Harbor, the Caribbean, South America and Europe. Traders said part of Monday's gasoline price boost also stemmed from the fuel's latest five-day lifting cycle scheduling to move on the Colonial Pipeline. Gulf Coast ULSD also climbed a penny to 5.50/6.00 cents over after the Aruba news emerged. For more refinery news, please go to U.S. GULF COAST Scheduling Cycle 17 M2 conventional gasoline was seen done early at 17.75 cents under April RBOB futures, up slightly, then later at 14.25 cents under, up 3.50 cents on the day. Cycle 17 61-grade ultra-low sulfur diesel climbed a penny to 5.50/6.00 cents over the April heating oil screen. Cycle 17 54-grade jet fuel was flat at 2.00 cents over. Scheduling Cycle 17 heating oil was steady at 4.25 cents under. NEW YORK HARBOR Prompt F4 RBOB was done at 19.00 cents under, up 2.50 cents, while any-March barrels were done at 19.25, 19.00, 18.50, 18.25 and 18.00 cents under, up 4.50 cents. Early April F4 RBOB was talked at 17.75/17.25 cents under. Ratable April F2 RBOB was done at 0.15 cent over and flat to the May RBOB future contract on NYMEX. Ratable May F2 RBOB was done at 2.00 cents over June RBOB futures, while ratable June F2 RBOB was done at 2.65 cents over July RBOB futures. Prompt M4 conventional gasoline was called either side of 17.00 cents under, up about 3.50 cents, while any-March barrels were talked at 17.25/16.75 cents under, up about 1.50 cents. Prompt ULSD was done at 8.00 cents over for a barge load and 7.50 cents over pipeline supply, while any-March barrels were pegged at 7.50/7.75 cents over. Prompt heating oil was called 1.75/1.25 cents under, down 0.25 cents, while any-March material was talked at 1.25/0.75 cents under, up a quarter cent. Prompt and any-March jet fuel were pegged at 5.50/6.00 cents over, also unchanged, with supply changing hands at 5.75 cents over. March kerosene was pegged at either side of 11.00 cents over, up 1.00 cent, while ultra-low sulfur kerosene was talked at 15.50/16.50 cents over. MIDWEST Chicago Cycle 3 gasoline was seen trading within its established range at 7.00/5.00 cents under. Chicago Cycle 3 ULSD fell 7.50 cents a gallon to 17.50 cents under futures. Group Three gasoline rose a quarter cent to 17.75/17.25 cents under, while Group Three ULSD rose 1.50 cents to 2.00/2.50 cents over.