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1985 Ex Mod 2.5 NA diesel are equipped with Voltage regulator?

11K views 36 replies 15 participants last post by  SebaGaertner 
#1 · (Edited)
Hi there
I have a 85 ex mod 2.5 NA diesel
currently still has OEM 24v military power generator/alternator
and I was wondering if you guy's now if this defender has a Voltage Regulator and where would be located?

*Installed two new batteries & I disconnect negative ( truck shuts off )

* Fired up engine ones more let it run, after several minutes , Shut off engine
try to start engine and it wont start.. :(


Do you guy's have any advise?
 
#3 ·
My advice is to NEVER disconnect the battery when the engine is running. The battery stabilizes the alternator output and when you disconnect it you can create a huge voltage spike that can wreak havoc on your electrical system.
 
#4 ·
Oh no.
The regulator was a huge box with a large multi-wire cable going in.
Some were behind the seats mounted along the bulkhead.
They are NLS and when a NOS one is located they sell for really big money, like over $600, but there is no guarantee that the regulator is the problem.

If it were my vehicle, I'd rewire it with a new 12V system and get rid of the 2.5 N/A, replacing it with something that will get up to safe enough speeds to allow you to stay with traffic and not cause a highway hazard.

Good luck.
 
#6 ·
The 24V only trucks ended with the series.

A FFR defender will have a single battery under the seat to power the vehicle systems and duel batteries in the bed under the radio table for the radios.

------ Follow up post added January 19th, 2018 08:56 AM ------

Also nothing wrong with a 2.5NA. Most people that complain about them have very little time driving them. Its a solid engine you cant kill. 20-25mog and cruises you just drive with the pedal down and go as fast as it goes 60-65.

If your after speed and ex mod is the wrong rig for you.
 
#7 ·
As above, the vehicle systems are 12V and run from the under seat battery and 12V alternator. The regulator is built in. The 24V system is stand alone. You need to be more clear on the problem.
 
#8 · (Edited)
For clarification ex MoD Defenders can be found in 12v OR 24v configuration depending on model on year of production.
On a 1985 ex MoD that was Fitted For Radio (FFR) it will be equipped with a large 24v alt that is fitted to power the 24v military radios ONLY and is completely isolated from the 12v harness. All other electrical systems will be powered by the standard 12v alt. Just like a civilian Defender.
Now, after the MoD upgraded the Defender to meet NATO standards with the WOLF all systems on the truck are 24v.
There a literary more than 100 different variants of military Defenders is many different configuration due to mission requirments.
My advice is to also join an ExMoD group to learn all the ends and outs of military Defenders.
 
#18 ·
I agree with UC4ME
Will be upgrading the engine to 200 TDI with 24V system
Why?
Because will be installing a 9500 Winch and will come in handi.

So
Does anybody know what is the box behind the passenger seat?
I disconnected two of the wires that go that box and I'm hopping that is not causing the
battery drainage ?
 
#14 ·
Thank you guy's for the support, advise & Electrical Wiring Diagram ...

* Today I got two new batteries
* I will be doing so testing on the alternator tomorrow & will advise you on findings
* Will also take some photos and try to post them so you guy's can advise me on the photos

Once again Thank you and will let you know tomorrow.
 
#19 ·
There are plenty 24v only ex MOD trucks out there. Seen them and worked on them.

Yes, taking of the negative fries up the voltage regulator, been there don’t that with a 24v one. Never happened to me with a 12v Generator although you still shouldn’t do it.

All the ones I have seen had the regulator in the alternator (not like the series where it was external)

Used or overhauled alternators go for about 150 UK pound

You don’t say why your engine doesn’t start anymore ? Doesn’t the starter engage ? Or does it and just doesn’t run ? In that case run a wire from the battery direct to the fuel solenoid and see if you hear clicking. Make sure you have 24V only.
 
#21 ·
You don’t say why your engine doesn’t start anymore ? Doesn’t the starter engage ? Or does it and just doesn’t run ? In that case run a wire from the battery direct to the fuel solenoid and see if you hear clicking. Make sure you have 24V only.
Yes is does start wit the two new batteries and starts right away with no sign of the starter failing.
this Sunday morning will continue checking all electrical wires and make sure I'm not loosing
power .

The red wire you see on the photo is from the power converter located behind the passenger seat.
right now is disconnected.
 
#22 ·
I believe that box just above the inverter to be the regulator.
The screw on cap is for the cable that feeds the radios and other equipment.
The positioning of the cables indicate 2 X 12V batteries hooked in series to produce 24V.
 
#23 · (Edited)
I'll second Johan on this. I had an all 24V truck here too. Looked the same as yours from the pics. I ended up keeping the 24V since doing a proper job converting is not easy and the wiring diagram as posted earlier was not correct for my truck.

I switched to a 200tdi and installed a new 24v truck alternator (same size and mounting as standard 12V alternator that was on the 200tdi).

BTW it doesn't look like your ammeter is hooked up. Thin brown wires on the shunt box.
 
#24 ·
I went back and re-read this thread and based on the original post I assumed that you were asking about an exMoD FFR Defender 2.5NA diesel engine which would mean a 12 volt system with the addition of a second 24 volt system to run the military radios in the back.
The Series III were equipped with all 24 volt, but they had 2.25 engines. But like I said, there are 100's of varieties of exMoD Land Rover.
Attached is a link to a very good ex MoD restoration page that covers 24 volt system in-depth. https://www.winwaed.com/landy/mil/military.php
 
#28 ·
Wolf's were mid-late 90's vintage 300 tdi powered trucks. You appear to have a 80's 2.5 natural FFR 110. The generator you pictured was typically wired up to only recharge the radio battery's which were in a box right behind the front seat bulkhead and not ied into the vehicle electrical system. The vehicle system was typically charged by a wimpy little 45 amp alternator with internal regulator.
 
#31 ·
I'm a little confused with your situation.
Can you clarify the following:
1. Do you have a 1985 ExMoD Defender from the British Military?
2. Is it a Fitted For Radio (FFR) ExMoD?
3. Does it have a 2.5 NA Diesel Engine?
4. Does it have the 12 volt alternator PLUS another separate larger alternator for the 24 volt system?
5. Are you attempting to power ANY of the vehicles components with the 24 volt system?
I'm not trying to be a smart ass or condescending but I don't understand what exactly you are wanting to know.
Most of what you keep asking was explained in the FFR wiring diagram that has been provided as it is the exact wiring diagram for a Military FFR Defender.
I know wiring can be hard to sort through so exact communication is critical.
 
#32 ·
Would it be possible for you to post a picture of the right side of your engine? Also, what is the VIN? Do all the VINs match? (Should be one on the side of the seat box, one on the top of the brakes, one on the front of the chassis.)

Mike & Carrie
 
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