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how to identify model of alternator

PostPosted: Mon Aug 10, 2015 5:13 am
by Milt
My label is partially missing, but the alternator is a 105 amp model from mid 1990's. I had a terrible voltage spike while charging and currently have it at an alternator shop to inspect the stator (spelling?) and considering replacing all the diodes. I suppose alternator replacement would be considered as well, but not sure what to look for until the old alternator is identified for mounting purposes. I have it installed on a 27 hp Yanmar 3gm30f diesel. thx -- Alan

Re: how to identify model of alternator

PostPosted: Mon Aug 10, 2015 12:04 pm
by Coulomb
The replacement would be the 4023-S for the Yanmar engine.

If you're lucky, a local alternator repair shop will use the high temperature parts necessary.

Re: how to identify model of alternator

PostPosted: Tue Aug 11, 2015 12:55 pm
by Milt
OK, I can just make out the "1023" model number, shown as a 105/120 amp output ... If I figure out how to post a pic to this forum I will so so! In the meantime, my local shop (he repairs mostly starters and alternators from cars and tractors, not the high out put style like this alternator) feels the stator (spelling?) is bad due to its COLOR -- that being black, even though all the wires test as OK and the stator wire does not test as grounded. He felt the black stator wire shown it had been overheated, even though to me it looks mostly to be a black enamel paint coating! The diodes are another problem in that his supplier shows them as a Delco number, but his supplier cannot supply them! Are their sources for the diodes to purchase for rebuilds? The diodes are: (negative) MR5010R 9045, MR5010R 9045, MR5010R 9045 and (positive) MR5010 9043, MR5010 9044, MR5010 9044 ( a total of 6 diodes).

Re: how to identify model of alternator

PostPosted: Tue Aug 11, 2015 1:02 pm
by Milt
I am attaching pics of my alternator

Re: how to identify model of alternator

PostPosted: Tue Aug 11, 2015 1:02 pm
by Milt
the stator

Re: how to identify model of alternator

PostPosted: Tue Aug 11, 2015 1:03 pm
by Milt
the diodes

Re: how to identify model of alternator

PostPosted: Tue Aug 11, 2015 1:03 pm
by Milt
the front case

Re: how to identify model of alternator

PostPosted: Tue Aug 11, 2015 5:58 pm
by Coulomb
That's a 1023, replaced by the 4023. It has a 2 inch mounting foot.

Re: how to identify model of alternator

PostPosted: Tue Aug 11, 2015 9:37 pm
by Milt
I see rebuild kits available for the 4023 ... parts no longer available for the 1023? (like diodes!)

Re: how to identify model of alternator

PostPosted: Wed Aug 12, 2015 6:04 pm
by Coulomb
Parts in the 4023 kit will also fit, (and upgrade) the 1023.