Detroit 8.2 alternator

Covers engines and transmissions
Joeoren
Posts: 24
Joined: Wed Nov 11, 2020 6:08 am

Detroit 8.2 alternator

Post by Joeoren »

Hi everyone just had my alternator die on me in the middle of a road trip luckily I was able to start by jumping from the house battery's and making it back to civilization.

I'm having an issue figuring out what alternator my rig has its a 1990 safari serengeti with a detroit 8.2t 225hp
The alternator has zero marks on it Maybe a sticker fell off or was removed not really sure. My rigs book has a old part number for the alternator but doesn't get me anywhere nothing online and napa and other part stores say it returns nothing similar to an alternator.

I'll have it removed soon so I can post some pictures on Monday.

Thanks for any help guys!
1990 safari serengeti High Tech editon 8.2T Detroit AT545
2009 Subaru outback xt - Toad 1
1999 mazda miata - Toad 2
wolfe10
Posts: 222
Joined: Sun Oct 27, 2019 4:12 pm

Re: Detroit 8.2 alternator

Post by wolfe10 »

To start identifying the kind of alternator you have, carefully write down exactly what terminals/wires it has going to it.

Common ones are:

Ground
B+ which is alternator output
IGN (ignition hot)
Sense (sense wire from chassis battery side of diode-based isolator)
Brett and Dianne Wolfe
Ex: 2003 Alpine 38'. Ex 1997 Safari Sahara. Ex 1993 Foretravel U240
Moderator, FMCA Forums 2009-2020
Chairman, FMCA Technical Advisory Committee 2011- 2020
Moderator, http://www.dieselrvclub.org/ (FMCA chapter) 2002-
Joeoren
Posts: 24
Joined: Wed Nov 11, 2020 6:08 am

Re: Detroit 8.2 alternator

Post by Joeoren »

Here's the number my book references I was looking at the wrong part number.

55700CX

Some sites have it as a oshkosh truck part number which is correct for my chassis. I'm not going to order anything until I get my unit out and take pictures of the wiring just incase.
1990 safari serengeti High Tech editon 8.2T Detroit AT545
2009 Subaru outback xt - Toad 1
1999 mazda miata - Toad 2
stuplich@ymail.com
Posts: 1146
Joined: Mon Oct 28, 2019 8:51 am

Re: Detroit 8.2 alternator

Post by stuplich@ymail.com »

Joeoren wrote: Sat Jan 01, 2022 5:24 pm Here's the number my book references I was looking at the wrong part number.
55700CX
Some sites have it as a oshkosh truck part number which is correct for my chassis. I'm not going to order anything until I get my unit out and take pictures of the wiring just incase.
Joeoren
Once out I suggest you take it to an alternator rebuilder near you.
Mel
'96 Sahara 3530, mine since '01
250 hp 3126 Cat, MD3060 Allison
Joeoren
Posts: 24
Joined: Wed Nov 11, 2020 6:08 am

Re: Detroit 8.2 alternator

Post by Joeoren »

Here's the alternator tag
Attachments
20220103_130149.jpg
20220103_130149.jpg (5.24 MiB) Viewed 5723 times
1990 safari serengeti High Tech editon 8.2T Detroit AT545
2009 Subaru outback xt - Toad 1
1999 mazda miata - Toad 2
Norcalbruce
Posts: 19
Joined: Fri Jan 31, 2020 9:05 am
Location: Northern California
Contact:

Re: Detroit 8.2 alternator

Post by Norcalbruce »

Hello, I'd like to suggest to just take it to a rebuilder. I'm lucky to have one 30 miles from the home port.
The shop is in Hamilton City, Calif. it was a rebuild on mine, all new for $100+ and two days.. I'm a lucky man. B.
Bruce 'n Jenny
1996 Safari Serengeti Mid Door
Cat 3126, Allison
'Someday' is on the Road...

From The Ground Up Farms, 501C3
Chico California 95926

The bitterness of poor quality remains long after the sweetness of low price is forgotten.
Joeoren
Posts: 24
Joined: Wed Nov 11, 2020 6:08 am

Re: Detroit 8.2 alternator

Post by Joeoren »

Went to a couple local places here in arizona and everyone kept telling me just get a newer style alternator.

I bought the rebuild kit for it and i am going to try to rebuild it in my spare time and keep as a spare.

However I decided to order a delco 28si which is a direct replacement for my unit and it seems they offer a lot of upgrades to the older style units aswell as upgrading the amperage to 200v. Hopefully this will work as two shops assured me it would.
1990 safari serengeti High Tech editon 8.2T Detroit AT545
2009 Subaru outback xt - Toad 1
1999 mazda miata - Toad 2
Robert K
Posts: 105
Joined: Mon Oct 28, 2019 2:27 am

Re: Detroit 8.2 alternator

Post by Robert K »

rebuild the Leece Neville .I made the mistake of getting a new Wilson rebuilt.
My alternator rebuild says they are built a lot better.

I got the rebuild from NAPA
Bob
96 Serengeti 37'
3126 Cat
6 speed Allison
2011 jeep wrangler towd
TDJohn
Posts: 552
Joined: Sun Oct 27, 2019 11:34 pm

Re: Detroit 8.2 alternator

Post by TDJohn »

Joeoren wrote: Tue Jan 04, 2022 10:31 am Went to a couple local places here in arizona and everyone kept telling me just get a newer style alternator.

I bought the rebuild kit for it and i am going to try to rebuild it in my spare time and keep as a spare.

However I decided to order a delco 28si which is a direct replacement for my unit and it seems they offer a lot of upgrades to the older style units aswell as upgrading the amperage to 200v. Hopefully this will work as two shops assured me it would.
The 28SI is an excellent high output alternator that has a great ability to give the majority of its output at idle. I upgraded to a 28SI in 2019 and it is far better then the 22SI I had. The only issue is that the unlike the Leece-Neville, and the 22SI, the 28SI is not a self exciting alternator, so you would have to either eliminate the diode based isolator, upgrade to a new larger isolator that has the fourth "E" terminal, or I can provide you with a schematic where you could install a relay that would allow you to use your original isolator. In reality, it is very likely, that your original isolator is only rated for 120 to 160amps, so you will need to upgrade anyway. You could also easily use your boost solenoid (assuming you have one on your older coach) as a combination of both, a boost solenoid and an isolator. Or you could install an additional solenoid. The other option is to buy a new Leece-Neville alternator (they are made in NYS) and keep your old one as a spare. If you do decide to go with the 28SI, make sure you order the one with the stud terminals on the back side, not the plug in pig tail style, and that it is the larger J180 hinge mount. They come in two sizes that look similar, but being that you have a Leece-Neville, that means you take the larger size. AC Delco makes a small and large J180 hinge mount style, and either one will fit, but if you end up with the smaller one, your belt will likely slip, depending on the belt tensioner style you have. (ask me how I know). One more thing, either brand alternator has to have a remote sense option (S) terminal and relay (R) terminal. The R terminal is needed to operate you tachometer and the remote sense terminal is needed to compensate for the voltage drop of the diode based isolator and the long wire run from the alternator to the batteries, which is very important for proper battery charging.

If you have more questions or want to discuss the various options mentioned, send me a pm and I will get back to you in a reasonable time. Tomorrow and especially Friday will be busy for me, so bare with me.
John
'95 Serengeti, Cummins C8.3-300
Allison 6spd.
Joeoren
Posts: 24
Joined: Wed Nov 11, 2020 6:08 am

Re: Detroit 8.2 alternator

Post by Joeoren »

John your a legend. thank you so much for the info because i honestly thought the 28si would just be a drop in solution.
heres some things:

my current pulley setup is a v ribbed 2 belt setup.

here is the alternator that i ordered: i believe its the correct one.
new 28si specs.jpg
new 28si specs.jpg (7.45 MiB) Viewed 5661 times

my current battery isolater is a 3 post sure power industries model 1202
sure power industries model 1202.jpg
sure power industries model 1202.jpg (5.91 MiB) Viewed 5661 times
i guess ill upgrade to this one: unless you know of a better one john?
Cole Hersee 48162 4-Stud 200 Amp 12-36V DC Battery Isolator

im also going to replace most the cables/terminals because some of them are just horrible.

and another question i have is what exactly is this underneath the battery isolator?
below the isolator - what is this.jpg
below the isolator - what is this.jpg (5.76 MiB) Viewed 5661 times
1990 safari serengeti High Tech editon 8.2T Detroit AT545
2009 Subaru outback xt - Toad 1
1999 mazda miata - Toad 2
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