Have a volvo I/O with the 270 HP 5 liter SX with EFI. Bought it new 10 years ago and has 275 hours of freshwater lake use only. Dealer after de winterizing explained to me how important this little part is to be replaced EVERY TWO YEARS. Mine is stock. They have the part for about $75 and will install it for ANOTHER $200. I keep a close eye on my temp and it is fine. Never gets near hot temps. I baby this boat. I am super paranoid now though and have went back to school so I could afford the part, just not the other two hundred dollars to have it installed. I am pretty mechnically inclined and have done some other repairs to my boat. Is this a difficult repair?? Where is the part located on the motor?? Half the battle working on the boat is gettting to the part. Any and all input would be appreciated. Thank You...