greetings,
I have a 1994 Volvo 940 wagon. I bought it from an individual.
It is the B230F four cylinder naturally aspired engine. The alternator is not working. It has a Nippon Denso 100 amp alternator.
As I search I am only finding the 80 amp alternator for the naturally aspired engines. The turbo engines seem to use the 100 amp.

Does anyone know if it is supposed to have the 80 or 100 amp alternator or does it matter very much?

Thank you for any help!
Eric

Dear enrique442,

Hope you're well. The 100-Amp Nippondenso alternator (Volvo #3544119 > #5003807) was standard on all post-1990 740 and 940 normally-aspirated cars sold in North American markets. The 100-Amp unit replaced an 80-Amp unit. Cars with turbo-equipped engines seem to have been equipped with a Bosch alternator (Volvo #9447865).

Parts for the Nippondenso alternator may be had from Barsanco, a firm in Michigan. I believe the following link is to the correct brush for your alternator, see: http://www.barsanco.com/part/217-510.html .

Barsanco's site shows this part as available. The specifications for this brush:
Nippondenso Brush (FA-140)Nippondenso Units) 12 Volt *** 15mm Length *** 7mm Width *** 5mm Height *** 48mm Lead Length.

Call Barsanco at 1-800-421-3374 or e-mail at info@barsanco.com to confirm fitment and availability. I've not done business with Barsanco, so do not know how whether they sell to retail customers.

Please post back with your findings.

Hope this helps.

Yours faithfully,

Spook

Hi Eric,

Ampere-wise 80A or 100A doesn't make much a difference for normal engine operation except maybe when you simultaneously use high current equipments like headlights + foglight + AC + blower (+ seat and side mirror heater too if you have it).


Unless you have another car to use by you'd need to replace your alternator ASAP or you'll keep draining the battery. In my experience, my 1994 940 Bosch car is only good for about 1 hour of driving to look for alternator shop before it runs out of power (this with AC + blower + headlights = Off).


If you have another car to use by you have the time to search/order for a new set of brushes for the Denso. If you have automotive electrician (those repairing starters/alternator/headlight/tail light wiring etc) at your township you could dismantle your alternator bring it over to the shop and have it fixed within a few hours. Otherwise ordering online would take a few more days.


If you plan to get a Bosch alternator make sure the mounting and wiring points are the same. Some Bosch use female spade connector for the D+ terminal, some use ring terminal. But these only require minor modification.


Alternator's depth (front to back dimension) is another thing to consider if you have AC. You may have AC pipes (from the compressor) running close to the back of your alternator. Yes you may use larger diameter drive belt to get it clear of the pipes but soon you'll be out of adjustment range. Get the right replacement in the first place to avoid all these. Otherwise there's not much else to consider for the conversion.


Regards,
Amarin.

greetings,

Thank you aleekat, KlausC, and rstarkie for your help!
Very good information and links!!!
I will check the brushes and see if I can find some new ones!

Also, would a 100 amp Bosch alternator(It is bigger than the Denso.) fit in the place of the Denso on the 940? Some info in one of the links made a reference to doing this.

blessings!
Eric

The Nippondenso and Bosch alternators interchange. The mounting and adjusting points are the same.

Although you've had trouble with the Nippondenso alternator, they are considered superior to the Bosch units. The Bosch is still a great alternator and they give little trouble. The Nippondenso is said to have better voltage regulation.

Make sure you have a good ground connection on the alternator, and the field wire is connected and supplying voltage from the instrument cluster.
--
john

As noted they are interchangeable.

Have a look at the brushes:

https://www.brickboard.com/RWD/volvo/1470276/denso_alternator_brush_set_replacement_pictorial.html

Good luck,
Randy

Did you take the back of the alternator off and check the brushes on the voltage regulator? Much cheaper than replacing the alternator.
--
Keeping it running is better than buying new

hi klaus- hope all going well. question about volvo alternators. my 92 245 which ive had since 2011 runs well. only annoyance is the well known electrical gremlins in 240 culture. have never touched the alternator in mine. what is the output of the standard alternator in this model. basic one in old american tanks was 35- 40 amps. check my output at idle about once a month and it shows a steady, consistent 13.5- 14 volts. know about the brushes but havent had to replace them yet. appears easy in a 240. local gal here told me (89 245) this past summer hers wouldnt start and a local clip joint mechanic replaced the alternator for $700. afraid she went to the cleaners. hers looks like a hippie peace van from woodstock. anyway going to figure out how to check amp output at idle- do you know the hook up? get volts at idle across the battery terminals. thanks tons oldduke

Checking voltage output is easy. Start the car, pull off the positive cable from the battery and check the voltage from that cable to a ground point. If the engine dies, both brushes are no longer making contact inside the alternator.

If one brush still works, the voltage will be low.

Check your neighbor's car at the battery, with the headlights on, AC running. You should still get 14+ volts across the pos&neg posts.

Did she get ripped off? Probably, unless it was a Mercedes and the bearings in the alternator disappeared. Shops normally replace the entire alternator rather than the regulator ($50-100) or even just the brushes ($10). They make more money that way. And it depends if the alternator needs to come off the replace the voltage regulator/brushes.
--
Keeping it running is better than buying new

Hi Klaus,

"Checking voltage output is easy. Start the car, pull off the positive cable from the battery and check the voltage from that cable to a ground point. If the engine dies, both brushes are no longer making contact inside the alternator."


The procedure you've just outlined is NOT for fuel injected car. Lifting the positive cable off the battery (engine is running) while alternator still connected to car's positive cable could damage the ECU. The switching diodes in the working alternator produce voltage spikes that are suppressed by the battery. Unsuppressed spikes could damage the ECU and cause engine non-start.


It is okay to do this in a carburettor car which I have done many times. Start the dead car with a good battery then replace it with the previously half-depleted battery while engine is running (this when I have no jumper cables to use).


Regards,
Amarin.

Unplugging the positive cable will not hurt the computers. They don't use 14V from the battery, they use alternator output which is reduced to around 9V or less. Any 'spiking' from the diodes would be death to many 12V bulbs.

Your wife's tale would require the battery to have 3 terminals: one for ground, one for alternator input, one for electricals.
--
Keeping it running is better than buying new

Doesn't matter. Previous owner could have replaced it from a pull a part.
--
Post Back. That's whats makes this forum work.