I have the same issue with my 2016 Scarab 165 Ghost. To be frank, I didn't even realize the boat was overheating, I just thought it was using too much coolant, as I have to top up the coolant reservoir almost every time we go out. But there have been no warning alerts on the dash about overheating, and no error codes that I can see. However, on Sunday we had the boat out and we had 4 people and some added ballast in the back with a wake shaper on the side and my son was doing wake surfing when the boat just died from overheating. It wouldn't start again. We let it sit for 30 minutes and it started up again and we gingerly headed back to shore. We were completely out of coolant after filling it up on Friday. I may have the same issue as I am using the orange coolant that is recommended in the manual, however, the original coolant could have been green. I don't know as the coolant tank was empty when I got it. HI could flush the coolant, as recommended above, however, as I'm losing coolant, I'm assuming there must be some issue with the coolant system itself as it is supposed to be closed loop. My buddy has a different boat with the same engine (except his has the supercharger) and he says he has never had to add coolant, There is no real Scarab dealer in town, so no way for me to get the coolant system pressure tested. Does anyone know any other way to try and find out why I may be losing coolant and why the boat is overheating? Also, if anyone has any additional info on some of the points brought up in this thread above I would appreciate it. How do I check if the ride plate is warm? Where is this cap that the guy said he tightened, which fixed his issue? Where is the water pump located and how would I replace this? Apologies for the noobie questions, but just getting started in the Scarab world and on this forum so any and all advice appreciated.
