TM 10-3930-671-24 The  negative,  rectifier  diodes,  are  pressed  in  the  rear housing (Figure No.  32). FIGURE NO.  32. CAUTION Do not attempt to substitute a replacement    diode    and    solder    the lead  to  the  diode  stem.    The  internal heat  of  the  alternator  may  rise  to  the point, to soften solder. The rectifying diode used in the ’TA" alternator have their leads  welded,  not  soldered,  to  the  stems   (Figure   No. 33). FIGURE NO.  33. Defective diodes may be pressed out of the heat sink or the  rear  housing  using  regular  diode  service  tools.    In every case, support the underside of the casting involved to prevent breakage (Figure No’s.  34 & 35). FIGURE NO.  34. FIGURE NO.  35. Do  not  press  diodes  into  same  fluted  opening  of  heat sink,  a  slight  twist  will  allow  new  diode  to  cut  its  own opening providing more efficient transfer of heat from the diode.  A typical diode installation tool is shown in (Figure No.  36). FIGURE NO.  36. Replace  rear  housing  or  heat  sink  if  either  is  cracked while exchanging diodes.   Retest  diodes  after  assembly prior to attaching circuit leads. F-289