On the 1984 300DT, how do I know what the alternator amperage is rated as? 55amp or 65amp?

If there is no tag on the Alternator with a part number of tells you the amperage you would need to do (with the correct equipment) a load test to find the max amperage.

Or you could assume that your Car has the alternator that the average Car came with at the time and not the higer amperage option.

If you are exchanging the Alternator for a rebuilt if you cannot tell what you have by looking at the exterior of the Alternator the Auto Parts Store cannot tell either.

Note exchange Alternators come withoug a Pulley or Nut and Washer so you need to be sure to get yours back (they will usually remove and re-install that on the replacment Alternator).

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84 300D, 82 Volvo 244Gl Diesel

I went with a 70 amp one that is used for a gasser w126 about 7 years ago.

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RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

91 W124 300D Turbo replaced, Pressure W/G actuator installed. 210K

90 Dodge D250 5.9 Cummins/5 speed. 400K

150.

If you're doing it anyway...

-Rog

But then you need to upgrade the wiring.

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Gone to the dark side

- Jeff

I'd upgrade as long as it was not heavier so as to not overload the brackets. As big as possible within this. Or require new wiring.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

I was being a bit cheeky, I'll admit. But after 30 years the wiring should probably get some attention anyway, so I wouldn't say that like it's a bad thing.

-Rog

The wiring is so short in the 124, from the alternator to the battery above it, easy to upgrade. I don't know if the OP's 123 is the same.

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Gone to the dark side

- Jeff

The Bosch AL-129-X 115 amp Alternator as used in the Saab`s around 1990.
It is a direct fit, just a bit larger but will go right in. You will have to increase the wire size. and I think change the pulley.

This was the talk of the town here on the forum a few years back.
I found one in PNP that wasn`t even dirty and got it 1/2 price.

This thread starts in 5-04 and last post 5-15 and 22 pages. Ya like to read?

http://www.peachparts.com/shopforum/diesel-discussion/93569-alternator-115-amp-bosch-al129x-works-123s.html

The 300D turbo used a 65 amp and the 240D used a 55 amp alternator as I remember.


Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

On a V belt? YIKES!

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CENSORED due to not family friendly words

On double belts? Yep.

-Rog

I'd go bigger.

FWIW, I modded my 617 bracketry to accept a Delco 22SI and machined the pulley to fit the alternator. The dual V belts handle it just fine, I can maintain charging voltage with all accessories AND the glow plugs running and not chirp or squeal a belt.

Lots of power is NICE.

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617 swapped Toyota Pickup, 22-24 MPG, 50k miles on swap

AFAIK the later Mercedes 143 amp alternators should work, I put one in my 190E and put that alternator in my dad's 240D

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Current: 1975 450SEL, 83 300D, 88 Yugo GVX, 90 300D OM603 swap, 91 F150 4.6 4v swap, 93 190E Sportline LE 3.0L M104 swap, 93 190E Sportline LE Megasquirt, 03 Sprinter, 06 E500 4Matic wagon.

96+ GM diesel trucks use a 124/140 amp alt direct bolt in, all ya need is a cord adapter to the resistor light socket for field.
Might be easier to find...

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

fatty wagons use to sell a upgraded alt,for their electric wvo conversion,you don't need to mess with wires for theirs.I went with the cheapest 2 years ago,and its fine on my w126.

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1999 w140, quit voting to old, and to old to fight, a god damned veteran