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- - Alternator decoding (https://67-72chevytrucks.com/vboard/showthread.php?t=850996)

72c20customcamper

02-28-2024 11:50 AM

Alternator decoding

1 Attachment(s)

I’m thinking this is the original alternative for my 1968 part number 1100794 = 37a date code 7L8 I’m thinking that stands for 1967 December 8th am I off base ? I’m putting new bearings in it regardless it was charging but howling. I took it off the 68 stepside

too much stuff

02-28-2024 12:20 PM

Re: Alternator decoding

Yes, it appears correct for your truck. 1968 307, 327 or 396 37amp.

72c20customcamper

02-28-2024 12:38 PM

Re: Alternator decoding

Quote:

Originally Posted by too much stuff (Post 9291522)

Yes, it appears correct for your truck. 1968 307, 327 or 396 37amp.

250 too?

Wrenchbender Ret

02-28-2024 01:11 PM

Re: Alternator decoding

Test your diodes while you have it apart. A bad diode will cause a noise similar to a brg.
The alt will still charge with an open diode but will have much lower output.

George

72c20customcamper

02-28-2024 01:37 PM

Re: Alternator decoding

5 Attachment(s)

Quote:

Originally Posted by Wrenchbender Ret (Post 9291538)

Test your diodes while you have it apart. A bad diode will cause a noise similar to a brg.
The alt will still charge with an open diode but will have much lower output.

George

Front bearing was toast was actually hard to turn the shaft . Rear wasn’t to bad but I replaced it to . Spins nicely now

54blackhornet

02-28-2024 03:36 PM

Re: Alternator decoding

I have a noisy one also. Can you elaborate a bit on the complexity of swapping out the bearings. Mine charges great but it is in need of new bearings for sure…thanks !

too much stuff

02-28-2024 04:10 PM

Re: Alternator decoding

Quote:

Originally Posted by 72c20customcamper (Post 9291524)

250 too?

Dec 8 of 67 is correct. My book only covers V-8, but may have been used on the 6 cyl also.

72c20customcamper

02-28-2024 04:26 PM

Re: Alternator decoding

1 Attachment(s)

Quote:

Originally Posted by 54blackhornet (Post 9291591)

I have a noisy one also. Can you elaborate a bit on the complexity of swapping out the bearings. Mine charges great but it is in need of new bearings for sure…thanks !

Very easy front is held in with cover with three screws just falls out . The rear needs to be pressed out and in but it’s really a simple job you will need a piece of thin wire to hold the brush’s in I use a small finish nail you can see it in this picture

Wrenchbender Ret

02-28-2024 10:14 PM

Re: Alternator decoding

Nice work.

George

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