I don think so
I own an '85 28.5 and I would say there there are not enough voids in the boat to accomodate all the batteries you would need to power an electric motor. Hec I am still trying to figure out where I can safely mount a 2nd battery, let alone a whole pile of them! Unless you replace the Yanmar diesel with a generator...but then you will not have enough room left for the electric motor! Properly maintained, these diesels should last upwards of 30 years. Yeah they are a bit noisy when running, but not intolerably so. The cutting edge in marine electric motor tech is currently being used on those mega cruise ships, powered by gas turbine engines. This tech is not going to see the pleasure craft market for many years to come. It'll be cool when it arrives in affordable fashion, if ever......meantime, keep the diesel.