Welcome, it is my sad duty to report that the scanned Old Town records stop just over 250,000 in 1984 so no one here can provide more detailed information for this canoe with serial number 278140. The last two digits of the hull identification number you provided indicate that it was probably built in February of 1986 for the 1987 model year. The information at http://www.usps.org/national/safety/HIN/HIN.pdf may help you interpret this number. I may be able to identify the model and material if you post some pictures and dimensions. Good luck,
The canoe is about 17'-3" long and 35.5" wide, the color is gray, and the seats are woven straps (looks like they were replaced at some point. Here are a few photos. One photo has the shadow of the model decal that once existed, but I can't make it out.
Thanks again for your help,