Hi Dubs, it was a dealer. They told me what it could possibly be and after service and diagnostics, it showed there was no problems on the print out sheets. All tubes are clear, water is circulating through the diode and thermostat, but not tell tale. The dealers told me the cost to put right, and what it could be. It would take 4 1/2 hours to strip the motor down. The dealer also told me that it would still be o.k to take out as it is and should the motor over heat, there are sensors that would put it in limp mode. Yes, the motor has been stood up a while and possibly some shale could be blocking it. I'm just wondering when the Yamaha dealer did the service on Friday, did they take all the tubes off from where the water spurts out, especially to the the tell tale outlet. If they did, they would have seen where the blockage was.