kapilamuni

Active Member
Hi,
Is it possible to fit a petrol alternator on a diesel P38, at least upto 1999?
Rave says;

Alternator
Make and type
V8 up to 99MY and diesel Magnetti Marelli A133, 100A, 105A or 120A .......................................
V8 from 99MY Bosch NC90/150, 150A .........................................................
 
So long as it is the same size with the same pulley - meaning - the drive belt is aligned correctly then you can fit what you like...

...using a lower powered alternator for prolonged periods may not charge the larger battery (often used for diesel engines) and in especially colder times you might find your battery going flat.

On the whole it is best to replace parts with the parts Land Rover designed for the job.
 
Yes, I agree on the capacity. Is it a direct fit with regard to mounting bolts position?
Diesel one uses 105A unit. BOSCH, MM, VALEO etc
 
Hi,
Is it possible to fit a petrol alternator on a diesel P38, at least upto 1999?
Rave says;

Alternator
Make and type
V8 up to 99MY and diesel Magnetti Marelli A133, 100A, 105A or 120A .......................................
V8 from 99MY Bosch NC90/150, 150A .........................................................

I don't know for sure but the one on the GEMS engine is in a different position and is a different shape. When mine went (before I even got the damn car home!) I found an OEM BMW one was actually cheaper than the Land Rover one. However, my set point is still 13.8V so I bought the mod Tomcat and Wammers use to raise the set point up above 14.2V and have been meaning to fit it for over a year. Not really a priority as I've had other issues to deal with recently.
 
Tell you what, I'll get the measuring tools out for the bolt holes next time I see a GEMS lump.
 
Get Mobiletron votage regulator with 14,7V setpoint, no more problems with undercharged battery.
Perfect for modern batteries.
 
Get Mobiletron votage regulator with 14,7V setpoint, no more problems with undercharged battery.
Perfect for modern batteries.

Ok for full calcium batteries, will destroy a antimony plated lead acid battery. Just as 13.8 will knacker a full calcium battery.
 
Thanks Grrr. I thought it's a direct fit asthe RAVE shows upto 1999 same thing.

What I have is PANASONIC 95AH , maintenance free, lead acid battery.
I can't fit a bigger battery as for the battery tray , this is the only size that fits.
Sometimes with AC on, Nanocom shows battery voltage as low as 11.5v.
May be it's possible to source a LR V8 alternator locally.
 
Thanks Grrr. I thought it's a direct fit asthe RAVE shows upto 1999 same thing.

What I have is PANASONIC 95AH , maintenance free, lead acid battery.
I can't fit a bigger battery as for the battery tray , this is the only size that fits.
Sometimes with AC on, Nanocom shows battery voltage as low as 11.5v.
May be it's possible to source a LR V8 alternator locally.

It may be. I just need a GEMS to have a look!

You could try replacing the gubbins in the top of the alternator. That would be cheap and easy.
 
You mean the regulator?
It's a DELCO unit and I got it repaired about a year ago. Can't locate parts as no model number to
identify the unit.
 
What is the charging output from your present alternator? Should be measured at idle just after start then at 2000 RPM with everything switched on. But i realise that could be difficult for you at the moment. Regulator can be upgraded to 14.2 volts for a lead acid battery or 14.5 part calcium battery or 14.7 if you have a full calcium unit. Obviously wiper rings need to be in good order.
 
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@2000 RPM with full load it's 13.2v.
Can't measure @Idle.
At least if I can get to 14.2v much better.

You will have to get a new 14.2 or 14.5 regulator. Yours will be currently a 13.8 set point. It is standard for the diesels. Possibly down because of worn brushes slip rings or just a tired regulator. Fitting a new regulator is a waste of time if the slip rings are badly grooved. They will need cleaning up. Take the old regulator out and check the slip rings before you decide the way forwards.
 

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