My 1996 (MY '97) Omega V6 2.5 auto has sprung a coolant leak. The hose that connects to the inlet port of the heater matrix bypass valve has split just behind the clip that secures it onto the spigot at the rear of the engine. I would appreciate it if somebody could identify the part number for this hose, please see the photo. The split is visible at the bottom right.
Also I am wondering why it split? Is it just old age or is it symptomatic of some other problem? Coolant was ejected from the split when the engine was up to temperature and the radiator fan started up. The heater was working OK before this happened. The temp gauge was pretty stable between 92-95 deg, so no overheating. And it always came up to temperature. So can I assume the thermostat and the water pump are working and nothing is blocked?
Also my bypass valve is marked "GM 90 457 649 -[A" and underneath "90 457 666". Why are there two part numbers? Since these valves are apparently problematic, I imagine I should replace it since I've got it off the car?
Many thanks,