another charging issue thread

[project911]

I've read through all the old threads again, and again, and again.

Here's what's going on.

Alternator was originally overcharging at 16 volts(~16.5 spikes). It was very random sometimes it would sometimes it wouldn't. It "seemed" more prone to overcharge when the headlights were on.

Replaced the belt and the voltage regulator.

Everything was perfect except if I turned the headlights on the alternator light would glow. Turn the headlights off and after a while the light would go out.

Took the car on a 300 mile road trip(no headlights), the alternator light never came on once.

I washed the car one night and took it out with the headlights on and haven't been able to get the alternator light to go out since.

Here are the stats:

Light is on constantly no matter the voltage reading.

1000rpms
Headlights on ~13.7 (it fluctuates between 14.0 and 13.0)
Headlights off ~13.0 (fluctuates, lowest value ~12.7)

> 1000rpms
Headlights off ~14.6 most of the time (rises to 14.9 after a while)
Headlights on drops to 14.4 (no matter if it was 14.6 or 14.9) and stays there.

Its weird because when the charging is low the headlights bring it back up. When the charging is high the the headlights bring it back down.

I'm thinking the 68ohm resistor might help cure the 1000rpm lower charging values from what I've read.

Any ideas ?

[project911]

John_Cramer - The light comes on when the blue wire is put to ground.

The battery voltage after the car is off is ~13.5 and drops to ~12.7 after a while.

The batteries have water over the plates.

The alternator is practically brand new, the previous owner converted to internal but I ran wires and mounted the regulator where the original external one was.

[Thack]

You can't use the external reg if you have an internal one. Disconnect it and route the other wires like it says in the Pelican tech section on this site.

Mike

[project911]

I'm not using an external vr.

I created a harness and mounted the internal as an external.

[project911]

Any questions about what I did can be answered here.

Int to Ext VR Conversion

[Thack]

All you have to do is cut the original plastic ducting on the alt. to make the new internal reg fit in the car.

Mike

[project911]

I didn't want it in that location due the heat in that area.

The vr's tend to die quickly subjected to so much heat by residing an inch from the block.

[project911]

Originally posted by john_cramer


I plan to do this in spring and put 2 bosch cans on the console so I can rapidly change between them (race car)

This another reason to relocate it. From the thread I linked above.

[Lorenfb]

Looks like you have one of those junk regulators, even though you mounted
it as an external. The alt. light coming "on" with the lights indicates a voltage
drop from the rear to front.

Thinks to do:

1. If the alt. is a Marchal with red plate, voltage at battery must be set (via the
regulator) to 13.5 to 13.7 at 2000 or the alt. will eventually fail. Most electronic
regs charge more than this.
2. All connections from the alt. (B+) to the starter to the battery must be
soldered.
3. The field (DF to case) resistance thru the brushes S/B about 6 ohms.

The 68 ohms resistor only helps "start" the alt. at a lower RPM, i.e. it provides
more DF current versus just the current thru the bulb. Also, remember that
the red plate Marchal/whatever is just a 55A alt. and as such will have a
problem charging a "monster" battery.

[Thack]

You obviously have a problem Project. I wish I could help. I just don't see why you would worry about a detail like that. 99% of the people on this list that have an internal reg have it in the alt. I think you miss-placed a wire but unless I could look at I couldn't tell you where you went wrong.
Follow the Pelican article closely and use the Haynes manual with a wiring diagram for reference. I think your reg is not working correctly.

[project911]

The alt is an aftermarket internal Hitachi.

I'll check the brush resistance, and solder the connections using the wiring diagram.

Thanks.

[project911]

Thack - thanks for the help. I did it to facilitate changing the vr in the future and to try and get more life from each one. I read alot about peoples experiences with internal vr's and tried to eliminate any weaknesses. I would rather plug in a spare vr than have to remove the alternator to replace it, especially if I'm on a long trip.

The wires are correct as I've checked them 5 times so far.

[Lorenfb]

I doubt that Hitachi makes the alt. They probably do make the little junk
reg., though. Someone just converted an old Marchal and put a Hitachi reg.
on the back. I've seen these before, and they're a waste.

[project911]

Actually I traced the part number to hitachi.

The vr is made by several sources. The original was a transpo ih211.

[project911]

So the marchal's came with internal regulators at one point?

[project911]

The previous owner had the alt installed by a reputable porsche shop (if that means anything).

The alt was $392 if that tells us anything.

[project911]

I think I get what you're saying.

A company is converting the marchal alternator's(new or refurbished) to internal by slapping on a crappy vr, and reselling them.

[Lorenfb]

You got it! The $392 is very high for just the alt. Pelican should be able to
do a lot better than that on the price.

[project911]

Thanks for the help so far.

The alt was $392 and the labor was $240 and they didn't unplug the original bosch vr when they were done!

[Lorenfb]

A total ripoff!