What's the recommended time to replace coolant hoses? My car is over 10 years old and they've never been changed. The all "look" good on the outside. I have had one recent issue in which I had the headgasket changed and the indy replaced the coolant and I've had a leak from the where the hose attaches to the water pump. I've tightened the clamp and hopefully that will eliminate the leak. Seems as if the removing and reattaching has stretched the opening ("mouth?") of the hose a little. Is there some sealant that is used when attaching hoses? Wondering if they should have all been changed when the headgasket was done. All the hoses combined come to less than $50. Labor should have been minimal since everything was apart and drained. Opportunity missed?