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38-116 Code 121 Powering Up Help
#22

Okay i think I am getting close to the issue. for the 8 mfd filter caps 141 and 142, I have connected both the positives together. They connect to one of the pins (top pin) on the filter choke (136) which itself has a connection to the 5 vac coming from the power transformer that supplies the rectifier plates. The bottom pin on 136 connects to a 0.3 cap (139) that connects back to the above positive connection from 141, 142. The bottom pin also has a connection to the positive end of the 8 mfd e cap (140).

I have the negative of filter cap 141 connected to the yellow/green high voltage center tap. I then have the 141 negative connected to the negative of 142. The negative of 142 (and 141) is then connected to the negative of the e cap of 140- this is also connected to a wire going to the field coil.

I have the positive end of the 10 mfd 50v ecap (140A) going to a ground lug. When I rebuilt the filter can that holds 140 and 140A I tied the two negative leads together - so there are three wires coming out of the 140 140A filter can - the positive end of the 10 mfd and the positive end of the 8 mfd and the tied together negative end. The positive of the 8 mfd goes to the bottom pin of the filter choke 136 described above. The positive of the 10 mfd goes to ground lug described above and the negative connects to the negatives of the 141 and 142 also described above.

I think my error may be that in the negative connections for 141 and 142, I used the existing negative lead on the filter can as my connection point for the above negative connections. It may very well be that the cardboard insulating rings are not working properly and the negative is shorting to ground at one or both of those points. I will check those this weekend and make a new tie point for the negative leads!

Andy Sorrell
Palmyra, Virginia


Messages In This Thread
38-116 Code 121 Powering Up Help - by AVSorrell - 07-17-2017, 08:12 AM
RE: 38-116 Code 121 Powering Up Help - by morzh - 07-17-2017, 08:21 AM
RE: 38-116 Code 121 Powering Up Help - by morzh - 07-17-2017, 09:47 AM
RE: 38-116 Code 121 Powering Up Help - by morzh - 07-18-2017, 08:57 AM
RE: 38-116 Code 121 Powering Up Help - by morzh - 07-18-2017, 12:05 PM
RE: 38-116 Code 121 Powering Up Help - by morzh - 07-19-2017, 09:08 AM
RE: 38-116 Code 121 Powering Up Help - by AVSorrell - 07-20-2017, 11:45 AM
RE: 38-116 Code 121 Powering Up Help - by morzh - 07-30-2017, 02:49 PM
RE: 38-116 Code 121 Powering Up Help - by morzh - 07-30-2017, 08:10 PM
RE: 38-116 Code 121 Powering Up Help - by morzh - 07-31-2017, 08:42 AM
RE: 38-116 Code 121 Powering Up Help - by morzh - 07-31-2017, 01:27 PM
RE: 38-116 Code 121 Powering Up Help - by Chris h - 09-26-2017, 01:19 PM



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