Volvo Paris Rhone Replacement alternator problem

[johnsilver2]

Good Day,
I have just bought a replacement alternator for the Paris Rhône fitted to my Volvo 2002 and I’m having a problem with the D+ terminal.
When fitting the charging indicator lead to the D+ the indicator light does not come on when the engine is not running. The oil pressure warning light and alarm come on! If I earth the charge indicator lead every thing comes on as it should. I confirmed all was ok with the Volvo panel by reconnecting the Paris Rhône.
Anyone else replaced the old Paris Rhône with the latest replacement sold by Keypart etc?
I connected the charging indicator lead to the W terminal and the warning light came on but stayed on when the engine was running. The alternator was pushing out 14.3V so no problem there. I don’t think the W terminal has a high enough voltage to put out the warning light as it just feeds the Rev counter. I borrowed another new alternator and had the same problem so it look like the D+ terminal is different on newer generic replacement alternators for the Volvo Paris Rhône.

Regards..........Andrew

 

[robmcg]

Probably your new alternator has an insulated return and the old one had a non insulated return. Similar problem replacing alternator on our Bukh, which I believe is identical to yours. For us, none of the panel gauges worked. I think we ran an extra negative wire which solved the issue.

 

[RichardS]

Probably your new alternator has an insulated return and the old one had a non insulated return. Similar problem replacing alternator on our Bukh, which I believe is identical to yours. For us, none of the panel gauges worked. I think we ran an extra negative wire which solved the issue.

That sounds very likely. I would have thought that alternators would normally be earthed through the mounting lugs but perhaps, like some starter motors and saildrives, alternators are sometimes isolated to help prevent electrical corrosion. Earthing the lead presumably turns it into a non-isolated alternator like the original.

Richard

 

[VicS]

Good Day,
I have just bought a replacement alternator for the Paris Rhône fitted to my Volvo 2002 and I’m having a problem with the D+ terminal.
When fitting the charging indicator lead to the D+ the indicator light does not come on when the engine is not running. The oil pressure warning light and alarm come on! If I earth the charge indicator lead every thing comes on as it should. I confirmed all was ok with the Volvo panel by reconnecting the Paris Rhône.
Anyone else replaced the old Paris Rhône with the latest replacement sold by Keypart etc?
I connected the charging indicator lead to the W terminal and the warning light came on but stayed on when the engine was running. The alternator was pushing out 14.3V so no problem there. I don’t think the W terminal has a high enough voltage to put out the warning light as it just feeds the Rev counter. I borrowed another new alternator and had the same problem so it look like the D+ terminal is different on newer generic replacement alternators for the Volvo Paris Rhône.

Regards..........Andrew

I agree with the other two posts ..... check that it does not have an insulated negative connection ....... but I am not so sure you'd observe what you have it it was insulated. It would not be charging the battery if there wa no negative connection.
Some versions of the engine had a fully isolated negative some did not but there appears to only be one replacement alternator for the entire range, which presumably will have an insulated negative and will require the addition of a negative/earth connection if there is not already one.

Are there any other terminals? D+ is not always the warning light connection.
61 , WL, L or IND are other possible labels for the warning light terminal

 

[SAMYL]

It may be one of the newer 'self exciting' type of alternators where the voltage going to the ignition light is no longer required to fire it up.

 

[LittleSister]

Was the replacement identical in term of fitting/adjustment lugs, and the various dimensions of the shaft for the drive pulley?

I ask because will probably need to replace a Paris Rhone 30A alternator at some point. Higher output (e.g. 75A) 'replacements' are advertised, but I am not clear how 'direct' a replacement they are.

I also wonder whether the body of the alternator would be significantly bigger for the greater output replacement, as there's precious little spare room around the alternator in my engine's installation.

 

[johnsilver2]

I got the replacement from Keyparts and is supposedly the direct replacement for the 50A Paris Rhône circa 1988 which has been superseded.
It has all the same terminals B+ B- D+ & W. The B- is the earth so I will run a wire containing a bulb from the D+ to the B- to provide the earth required for the warning indicator when the engine is not running. The bulb will provide some resistance to stop too much current escaping to earth when the engine is running. Sound like a good plan based on the advice from Rob Richard and Vic?

Regards.......Andrew