I changed out the power transistor in my e24 when I changed the blower motor about 6 months ago, and I have not had a problem since. There are some really good instructions at http://normgrills.net/bcg/Blower_Transistor.htm, but I deviated a bit from the way Bob fixed his:

He recommends using a 2N3771 transistor, I stuck with the original 2N3055, mostly because it's easier to find (Radio Shack has them). If you can find the 2N3771, it's supposed to last longer.

The transistor is rivited to the board, and Bob recommends using small nuts and bolts to fasten the new one. I riveted the new one in - just make sure that the blind rivets you use are long enough (had to re-do one because of that)

IMHO Bob does not say enough about proper soldering techniques. Get a good de-soldering tool if you do not already have one. It will help get rid of all the old solder and make the the end result a lot cleaner, not to mention making the old transistor a lot easier to get out. Make sure you have a good mechanical connection first before soldering. Tin the iron so it conducts heat better, touch it to one side of the connection and the solder to the other side. The solder should flow evenly and smoothly. If it does not. de-solder and do it again. DON'T GLOB THE SOLDER. Ahhh, don't you just love the smell of hot lead vapors and burning flux?

• 635 BLOWER MOTOR - tmwbmw 2004-07-20 23:08:39 (1144 views)
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  • damn thought you meant 635 motor with a blower! (nt) - Kevin Elmore 2004-08-26 01:08:32 (878 views)
  • yes, that can be readily fixed (url) - davidc 2004-07-21 13:09:39 (1071 views)
    • Re: yes, that can be readily fixed (url) - nealtech 2004-07-23 10:05:48 (3152 views)
      • Re: yes, that can be readily fixed - nealtech 2004-07-23 10:09:26 (833 views)