Sorry, I had not checked back in a long time. Because of the amount of water in the lines, I didn't even winterize the boat, just got bilge heater and am running the crusieairs to keep everything above freezing. It got down to 6 degrees last weekend but the lake water was still 60. So, do you have an easy solution?
I have your answer after a long journey with this issue . Let me know if you are still having a problem but I have the only cure . U will need to reconfigure the exhaust . Let me know how to reach u and I can explain . My issue was with same boat but with 502s .