D1 alternator

KorytheLorry

Member
Feb 1, 2020
6
2
Maryland
I'm on my third reman D1 alternator in as many years. The first was a Delco from Rock Auto, the latter two from Advance/Carquest. They all failed in different ways. What alternators are you all using? I haven't been left stranded but it's only a matter of time...
 

discostew

Well-known member
Sep 14, 2010
5,797
301
Northern Illinois
I would get a used genuine alternator from Tillery. I really don't think the alternator is a real common fail item. In about 20 years of owning Disco1's I think I replaced one bearing in the back of the case, and I replaced one alternator with another used one because I had no tach on cold starts.
 

p m

Administrator
Apr 19, 2004
14,601
205
55
La Jolla, CA
www.3rj.org
I had probably four or five failed alternators. All but one - brushes, one - brushes and one blown diode in the rectifier. One needed both front and rear bearings.
Piece of cake to rebuild at home.
 

Tugela

Well-known member
May 21, 2007
4,285
155
Seattle
I had probably four or five failed alternators. All but one - brushes, one - brushes and one blown diode in the rectifier. One needed both front and rear bearings.
Piece of cake to rebuild at home.
From where did you source your parts?
 

discostew

Well-known member
Sep 14, 2010
5,797
301
Northern Illinois
I suppose that's 2 alternator failures for me and 4 or 5 worst case? GM vehicles back in the late 90's early 2k used to eat alternator bearings. They told us it was because of etching from the rotating mass passing thru a really strong magnetic field. They lasted about 25,000 miles as I remember. Nothing you could do about it.
 

robertf

Well-known member
Jan 22, 2006
4,193
78
-
Ive had at least a half dozen failures. Some diode failures that would drain the battery, some tach failures, and some with really low voltage output.

Now that they dont cost $700 anymore I just throw a new one on at the first sign of trouble
 

discostew

Well-known member
Sep 14, 2010
5,797
301
Northern Illinois
I think I had a low voltage issue once. So maybe 4. I think it wouldn't charge till I took it off idle when it was cold outside. But after that it was fine.
 

best4x4

Well-known member
Mar 1, 2015
458
15
Beaumont, TX
I've had the cheap refurb/rebuilt units on used D1's I've bought take a dump shortly after buying the LR, but once I slapped in an OEM P38 unit I was good to go after that.

I did just have the OEM unit in my XD drop down to 12.1v. Removed it, took off the back and found the brushes were at their max travel and barely touching. I replaced the voltage regulator, and I was back up to 13.7-13.9v charging.
 
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Rocky

Well-known member
Apr 23, 2004
2,144
2
Red Sox Nation
Think I’m on my third unit since 1995, plus one ore I had Re manufactured. Current unit was new but shows that same no charge on start up regardless of temp.Since new to. I think it’s voltage is a little lower today than it was so perhaps it’s on its way out...