Mole Richardson Type 407, Baby Solar Spot, Lighting Bulb Refuses To Come Out

Mole Richardson Type 407, Baby Solar Spot, Lighting Bulb Refuses To Come Out

Customer complaint:  Can not remove the light bulb out of a Mole Richardson Baby Solar Spot.  It appears to be stuck.

Solution:   I tried to remove the bulb by wedging a straight blade screwdriver between the socket and porcelain bulb base.  The bulb was locked into the socket.  I called Mole Richardson and explained this problem to them.  I was told that some times the bulb contacts become pitted and make bulb removal difficult.  I would have to disassemble the socket.  The technical illustrations provided by Mole Richardson are very impressive and thus most helpful.  I had to remove the bottom of the unit by removing four screws that hold a box at the bottom of the fixture which holds the reflector, socket and pan/spot rails.  The socket is very complicated and is NOT recommended by anyone except a repair person who is totally competent to complete this repair successfully.  I found one (out of four) of the ceramic donuts cracked as seen below.  Once the two main metal contacts were removed the bulb pin was still stuck inside the socket.  The image below shows my attempt to use pliers and spin the connector around the bulb pin.  The pin was so firmly stuck that this attempt failed.  I had to break the bulb ceramic base so I could remove this contact and attack the problem while the socket was held by a bench vise.

Instrument socket shows contact holding bulb pin.
Instrument socket shows contact holding bulb pin.

 

 

I had to remove the metal contact (seen in above image held by pliers) and put it into a vise.  I then took a vice grip pliers and I must have spent over ten minutes spinning the bulb pin before it would come out of the contact.  I inspected both the bulb pin and the socket connector. The image below shows an extreme close up of the problem bulb pin.  Notice the extreme pitting.  The bulb pin should be smooth, not pitted.

Microsope view of bulb pin showing pitting.
Microscope view of bulb pin showing pitting.

I determined that I must replace BOTH instrument contacts.   Only one ceramic insulator circle was cracked but I ordered four in case one might break during installation and have some as spares.  The ceramic insulators only cost $2 each.  The repair parts cost about $68 with tax, not shipping.

Conclusion:  If you have a Mole Richardson Type 407 lighting instrument and the light bulb can not be pulled out of the socket, the bulb pin and even the socket might be pitted.  Send or take the instrument to a qualified repair facility.  Do NOT attempt this repair as the socket components are rather complicated to disassemble and even more difficult to assemble.  The purpose of this post is to show that the bulb pin may be pitted so the bulb can not be pulled out of the socket.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.