Yes, and in our waters needs to be done often. You should have a "blanking plug" hopefully wired to the transducer, it's to put in place of the 'ducer to stop water coming in while you clean. Most Raymarine's have a flapper valve that reduces the flow when you pull the transducer and there's little pressure so you don't get too much water before you get the blanking plug screwed on. Then you need a paper clip to push out the axle pin on transducer paddlewheel. Paddle may be cleaned with fine wire brush if metal, Plastic parts can be scraped with butter knife etc. carefully. We mostly get some kind of worm that leaves a white "casing" everywhere that fouls the paddle. I've attached link here to the manual for the ST50 speed,an older model, the Ray website has the manuals available online for most instruments.