Light socket blowing bulbs??

We had two new outdoor house lights installed on the front of our house by an electrician a few months ago. They replaced an old set of lights, which were on the house when we purchased it.
They are both on the same circuit and switched together. One of the fixtures continuously burns out. Both are rated for 100W max and we are using 60 W bulbs. The other light has never lost a bulb but we have lost 3 bulbs in 2 months in the bad light. I thought it might be a problem with rain and water getting into the fixture but the latest bulb burned out before we had any rain.
Does anyone have any suggestions or run into something similar?
Thanks Fred snipped-for-privacy@yahoo.com
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
John's two are right on. Vibration and a poor connection (heat) are typical causes. I will add one more. Are the lights you are using for replacements the same brand and type as the one that is lasting a long time (they make long life lamps and different shapes etc.).
Also one fixture may have a water leak or be in a position that allows wind to blow water into the fixture causing problems.
One last thing. Make sure that the socket in the one blowing lamps is not damaged and that the lamps are making good contact. It the center contact is bent down or it is corroded or if there are burn marks on it, that can also cause problems.
--
Joseph E. Meehan

26 + 6 = 1 It's Irish Math
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.