Hi everyone,

Red battery light came on in the last mile of a 140 mile drive.

Alternator/voltage regulator was replaced approximately 2 years and 25k miles ago with a Bosch reman AL117X (standard part available from this site).

Car off: Battery voltage = 12.6V
Car on: Battery voltage = 12.2V <- clearly not charging

- belts are OK
- Connector to alternator looked OK.
- I have a new voltage regulator on the way.

Is there anything else to check at this time or to look out for?

I am unfortunately really busy right now with work/school so I need this to be solved as quickly as possible, hence my call for other things to check.

thanks,
dd

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'85 300D, 'Lance',250k, ... winter beater (100k on franken-Frybrid 3 Valve Kit)
'82 300D, 'Tex', 228k body / 170k engine ... summer car
'83 300TD Cali Wagon 210k, wife's car

Since you have a new voltage regulator coming, I would try that first. The voltage regulator is a likely candidate and you don't want to risk messing something else up and having two problems.

Look for corrosion on the wires. Usually the battery's positive wire gets green in color. Corrosion adds resistance to teh wire and reduces the voltage to the battery.

Also the connector on the alternator could be corroded.

__________________
Closing the store
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charging now at 14.1V, back to normal.

Take a look at the brushes on my old regulator...does that mean anything bad is imminent for my alternator?

thanks for the help

Attached Thumbnails

 

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'85 300D, 'Lance',250k, ... winter beater (100k on franken-Frybrid 3 Valve Kit)
'82 300D, 'Tex', 228k body / 170k engine ... summer car
'83 300TD Cali Wagon 210k, wife's car

That bad brush looks like it wasnt seated on the slip ring properly. Looks like you have oil in there as well. Normally when the brush doesnt contact the idiot light doesnt come on before starting.

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Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving

I had a problem with the brushes "sticking in the bores" once. That may have been what you were experiencing. Or a a combination of the oil and some sticking. It actually looks like a piece of that brush broke off.

Last year I had a hell of a time getting the brushes to seat on the slip rings properly with the alternator in the car. I finally removed the alternator so I could install the new regulator properly. I'm glad I did. When I pulled the alternator I found that the bottom bolt was worn almost all the way through.

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AJ

1985 300D (SOLD)

that looks like a badly worn slip ring. or worn bearings have allowed the rings to slide out from position on the brushes.
pull the new brush back out, and see if the same wear pattern is on the new one.

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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!

That original regulator was put there by whoever remanned it at Bosch and the unit has 25k miles on it.

I'll see how the used regulator does and then I'll pull it out in a couple weeks when i have time to replace it with a new one.

Whats the life expectancy on a voltage regulator anyways? I feel like its more than 25k :-)

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'85 300D, 'Lance',250k, ... winter beater (100k on franken-Frybrid 3 Valve Kit)
'82 300D, 'Tex', 228k body / 170k engine ... summer car
'83 300TD Cali Wagon 210k, wife's car

The regulator last forever except for the brushes, which wears, but can be replaced. The brush leads are brazed on so a soldering iron will not remove the old brushes. Drill it out then solder the new brushes in.

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked