My costumer have a problem, the light bulbs in a resseset can start kliking after
Short time of work. The max W is 75w we used 65w and still kliking,
I moved the insulation from the and around the can, I checked the contact in the sucket,and I used switch not dimmer. Still kliking.
Any one can help?

Sos...
You should start a new thread instead of inserting your question at the end of a
Five year old question... start fresh,
Also please include more information, how many fixtures are on this circuit?
What size is the branch circuit breaker? Have you metered the load on this circuit?
The more information you can provide, the more useful the answers you may get.

Sorry man first time ever on the net with questions/
He has 7 lights on the circute and the breaker for the light is 15amp
The wire size #14 thhn. On the circute thare is no other load.
The ressest can are not AT/IC it built before it come to be a code.

If it is just this one fixture that is turning off, I would guess that it is the thermal overload in the fixture... does this fixture come back on after it cools down? If so, it is the thermal.
I see two options for you, one try a lower wattage lamp. Two, replace the fixture. You really can't do much with the thermal, as far as I know they don't sell replacements. If you bypass the thermal you violate the UL listing and may allow the fixture to overheat. An old work replacement is about $25 and is the "sure" solution.