I think some ppl have had success retrofitting the later style alternators to v-belt cars.

They are a newer, better design! The 90's S-class V-8's had a 143A alternator, the SL/E's had a 110A- both same design. 99-01 ML's all seem to have the 150A which is a newer design. 2 wires, the big one and a little to the switched source.

They seem to have much much higher amperage at lower speeds and they hold a steady 14-14.3 volts regardless of rpm or load.
I think the 150A spec is 110A @1000 rpm(alt, not crankshaft) and 150A @ 6,000 rpm.
Used they can be found $50-100 and a new brush reg pac (bosch only) is $25!!
Why stick with the old design and it's inherent limitations?

M

Did you get an OEM alternator or a cheap east asian Knockoff?
There is Louis Vuitton and east asian Louis Vuitton.

It was a Dixie rebuilt thru a local parts shop here. It's replacing the AL117X 70A alternator.
This rebuilt is actually putting out 80A at 2000RPM, so it's a pretty well rebuilt alternator.
I've determined that the general lack of charging at low RPM in these older cars is lack of a properly sized drive pulley. I made the driven pulley smaller by placing a washer between the two discs, and gained 2.5 volts. Now I've been successful in achieving an adequate charging voltage at 600RPM. My additional problem still exists however, high loads at low RPM drains the battery. This may require relocating pulley drive to a smaller pulley or upgrading to a newer alternator beyond the typical AL129X upgrade.

__________________
RIP: 80 300SD
RIP: 79 450SEL
2002 E430 4matic (212,000km)
2002 ML500 'sport'

____________________________
FACEBOOK: PANZER450

Contact a local alternator rebuilder, they will generally have a smaller pulley to fit your alternator.

Catastrophe: Two shredded alternator belts in 24 hours.

Lesson Learned: When I spaced the pulleys apart, I failed to account for the change in the center-line of the pulley path, and very quickly shredded two belts. Belts slip, pulley heats up bearings seize from the heat.

Anyway, that damned rebuilt alternator was crap. couldn't get it to charge at low RPM. It's Thanksgiving weekend(CAN), and I need to replace the alternator.
With the bearing seized, pulley screwed, I remember that I have an engine with accessories in the garage at my parent's house. A M117.983 engine from a 75 SEL. The alternator is corroded, the center section is rusty, but it has a belt on it. It looks like it hasn't turned in 35 years Take the belt off, if feels seized. Tap lightly with a hammer and it come free.
Awesome.
I decide to bench it and take a look. Brushes still good, on both sides. I was happy to see that it was an original Bosch alternator with original Bosch voltage regulator. The belt was in pretty good shape too. So I took the alternator, belt and bracket w/ toothed bolt and put it on my engine.

Installed with old belt, fire it up and everything looks good, sounds good.

get out the multimeter. 13.8 throughout the ENTIRE RPM range. NICE
add load at loaded idle, and voltage only drops to 12.6 rather than 11.5 Nice

I will never buy another rebuilt alternator as long as I live.

__________________
RIP: 80 300SD
RIP: 79 450SEL
2002 E430 4matic (212,000km)
2002 ML500 'sport'

____________________________
FACEBOOK: PANZER450