130A alternator upgrade

[jagwit]

The car does NOT need 130A!!!
___________

Even with Aircon and EFI (this car does not have EFI), the car does NOT need 130Amps.

THE MAIN AIM OF THIS REPORT IS TO SHARE ABOUT THE EASE OF IMPLEMENTING THIS UPGRADE AND POSSIBLY, HOW CHEAPLY IT CAN BE DONE

I had this alternator lying around in my garage and decided it had the best form factor for the conversion. The fact that is is a 130A alternator is actually rather academic. It comes off a Land Rover Discovery 2 V8, Land Rover Part no ERR6413 (Bosch)... but now its mounted to the Series 3.

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To mount this alternator:
1) Have the Poly-V pulley replaced with the smallest double V pulley they can fit. The belts only run about 2mm from each other and the pulley must match this criteria as well.

2) OPTIONAL: modify the mounting bracket as follows:
Original:


Enlarge the cutout in the bracket as below. This is only to give the alternator a larger range of movement to make mounting of the fan belts easier. Again, this MAY not be necessary. IF the car's bonnet was off, I would have tried without doing this mod.

Modified:


This modification is OPTIONAL. I believe the implementation can be done without enlarging this cutout.

3) Mount the bottom end of the alternator to the bracket using a threaded rod and spacers. I used a 10mm spacer on the engine side between the bracket and the alternator and a 77mm spacer on the radiator side of the alternator.

4) I made a new tensioning rod using an original tensioning rod (3/8" UNF) used on an XJS alternator (only because I wanted to preserve the original that came with the Butec) and a long M10 bolt which I welded to the side of the UNF rod. This made the 10mm rod line up perfectly with the hole in the tensioning block. Sometimes we need a bit of luck...

5) Wiring: Simply connect the Brown/Red wire to the D+ terminal of the alternator. Leave the Brown/Green wire disconnected at the alternator end. No other wiring mods are required. Also connect the thick wire to the large B+ terminal. Its not even necessary to disconnect the plug from the old alternator regulator.

EDIT: 6) There was no need to change the V-belts to different size.


Comments:
1) Now I'm going to set the car on fire right? The alternator is going to push 130A into wires not designed for 130A right? This will cause them to heat up and catch fire right? I disagree, but I don't have the energy/time to explain myself in this post.
2) If there IS one item in my setup that might protest, it is the large spade lug that connects the thick wire to the alternator B+ terminal. I do not believe this spade lug is up to the task of supporting the current that will be drawn when max amps are drawn (all lights, fans and AC on). I might add another, even thicker wire, terminated with ring lugs and run this directly from the alternator output to the battery +.
3) This alternator outputs 14.2V as measured on the battery.
4) Even though I used the smallest pulley the 10mm V-belts can handle, alternator speed is still a bit slow when the engine idles at low RPM (in Drive eg), due to the small crank pulley. Ideally, a larger crank pulley would have been nice.
5) I believe the 100A alternator (Magneti Marelli) from a Land Rover Discovery 1 V8 would work just as nice.

[Heuer]

An alternators output is dependant on revs much like a dynamo although not as compromised. Pulley size is the determining factor here - measure the crank pulley vs alternator pulley (2 3/8") to get the ratio. Because high output alternators have a very steep idle performance curve, bigger is not always better - at tick-over it may not be charging! Output will also decrease as temperature increases so you need to find out what the 'hot' output is. For example a unit rated at 60amp 'hot' will output nearer to 80amps when cold.


Using a 130amp alternator means you really should rewire with heavier gauge cable because although it will only produce sufficient current to meet demand a faulty battery cell could mean it goes to full output (160 amps cold) and that is going to be a problem.

[JagWaugh]

130A? What are you planning to do with all those Amps, spotweld?

[cactusman]

Well said Jagwaugh....pointless. only trucks and the like will ever need an alternator capable of producing 130 amps.

[jagwit]

130A? What are you planning to do with all those Amps, spotweld?

If I have to...

Like I said in my first post. I chose this alternator for its form factor, not its amps. It was lying in my garage doing nothing, so it cost me nothing to implement.

The car will only use what it needs, nothing more.

[MarekH]

We are very grateful but forgetful that exchange controls were abolished in the 1970s here in the UK.

People in the UK, or pretty much anywhere and everywhere, don't realise that the red tape and government tax intervention involved in money transfer and importation of goods into SA. I remember sending Philip a crank for his Land Rover a few years ago. Apparently he needed a government licence to import it. Heaven forbid anyone trying to send money OUT of South Africa, even via paypal.

If the alternator was sitting idle in the garage then that's why it was used.

Good luck.

Consider running the front lights directly from the alternator via a pair of relays on the picture frame.

kind regards
Marek

[jagwit]

Consider running the front lights directly from the alternator via a pair of relays

This is exactly what I did on my EFI'ed Jensen. Ditto the radiator fans. Doing so would bring great relief on that spade terminal on the alternator.

EDIT: On 2nd thought, might be a bit more challenging to accomplish this on the E, as it may not be quite as easy to get access to the headlight circuits. Will have a look though.

[Heuer]

High power headlamp upgrade details here: viewtopic.php?f=9&t=4919

Well done on the upgrade and making use of a spare alternator. Just make sure it energises at tick-over (as you point out, it may need a bigger pulley to increase revs) and keep an eye on battery health.

[jagwit]

Today must have been somewhere between 35ºC and 38ºC and I took her for a drive...

Temp gauge was sitting on the M of NORMAL most of the time, Aircon on, Battery gauge dead centre (it was sitting on the N of ON CHARGE as I left home).

When I got to about 1km from home I switched the headlights on as well (brights) and when I stopped in my garage, I let it idle (1000rpm on the Tacho) quickly opened the bonnet and connected my volt meter to the battery:

13.25V on the battery, Aircon on, both fans running, headlights on bright, ie max load on the alternator at max temp. Interestingly, the battery gauge was sitting deep into the discharge area.

I will be installing another thick conductor from the alternator soon, just for comfort and will then report if there are any changes.

[Heuer]

At tick-over with no ancillary equipment on you should be getting 14.3v. If not increase the throttle which should energise the alternator and see if the voltage rises. Ideally you need the spec sheet for the alternator as that will tell you the minimum revs required for output and the max revs it can take. You can then work out the ideal circumference of the pulley.

[jagwit]

You can then work out the ideal circumference of the pulley

A bit academic perhaps? The pulley on the the alternator is already as small as what 10mm V-belts allow. So, the only option is increasing the crank pulley (or water pump pulley) size. Neither of which appeals to me now. Besides, it seems to be charging fine at idle even before adding the additional conductor as below.

Anyway, had an energy spurt this afternoon, found some "welding cable" lying around (9mm diam, 63mm^2) , yes, like the "130A" also OTT, but again, IT WAS LYING AROUND, so I installed a length from the alternator output terminal directly to the battery.

Strictly speaking it would be better to have terminated it on the terminal right next to the battery but that is covered with a rubber boot and it seemed the boot would suffer damage if i tried removing it. So I terminated on the battery terminal.

My Fluke multimeter now measure 0.00V voltage drop between the battery terminal and the alternator output (did not measure this before - should have....)

The original thick brown alternator wire is connected as before, still using the spade lug on the alternator.

[Vegard]

Just make sure it energises at tick-over (as you point out, it may need a bigger pulley to increase revs) and keep an eye on battery health.

A bigger pulley will reduce the revs. That's what we fit on all our race Minis to help the alternator survive 8000 engine rpm.

[jagwit]

I may still replace the original Butec....

The motivation to do this alternator upgrade was based on the "Battery Condition" Gauge frequently reporting deep conditions of "Off Charge" when the Aircon and headlights were on and while idling.
Well, I have found the Battery Condition gauge to be giving substantially false and flawed readings. This thread explains it all: False Battery Gauge readings

Having corrected the reasons for the false Battery Gauge readings, I now believe the alternator upgrade as per the first post may have been unnecessary and I do intend re-fitting the Butec at some point verify this.

Will report back on this matter when I do.

[MLBS3V12]

For my part , As I do not have Butec, I'll use the same alternator than yours Philip. I finally found a pulley. It has had to be reworked as it was too thick to match with the output shaft.

[jagwit]

I may still replace the original Butec....

Having corrected the reasons for the false Battery Gauge readings, I now believe the alternator upgrade as per the first post may have been unnecessary and I do intend re-fitting the Butec at some point verify this.

Will report back on this matter when I do.

Well, I've decided to keep the 130A alternator, for the sake of having a modern Bosch, "easily" repairable alternator on my car for when I'm away from home.

BTW, the car still has not caught fire....

[MLBS3V12]

[cactusman]

At the risk of pointing out the obvious, installing a 130 amp alternator seems unwise. Let's look at the possible demands. Headlights on full beam. 10 amps. Side/rear/no plate/instrument lights....say 5 amps. The brake lights are on..4amps. Indicators on... another 4 amps. The heater blower is on....say 10amps. Then engine cooling fan is on....another 10 amps....and you have the radio on max vol....say 3 amps.....that is 46 amps....and I am ridiculously pessimistic. Added to this the battery is flat and being charged....say 20 amps....we have got to a theoretical 66 amps....
A very unlikely set of circumstances. SO why are people fitting an alternator capable of supplying an extra 60 plus amps? If there is a battery fault or wiring fault from the alternator the cabling should be able to carry 130 amps....no e type loom is built to any where near that specification. A land rover is presumably wired to accept such an alternator and will probably have more On board electrical gadgets plus a tow bar and split charge circuit to charge a large leisure battery in a caravan. If you really must fit a huge alternator you must address the cabling too.....and the same goes for those converting from a dynamo to any alternator. Chances are dynamo wiring will not be up to the output from an alternator as most standard alternators today can produce 70 amps whereas your trusty dynamo will produce about 22 amps....which is quite sufficient for UK cars ....mine runs a dynamo with no problems....just my take....

[jagwit]

SO why are people fitting an alternator capable of supplying an extra 60 plus amps?

As stated in post #1, its NOT about the 130A. It IS about the form factor and ease of installation.

I'm not ENCOURAGING anyone to install this alternator. I merely share what I did and WHY.

[cactusman]

Indeed...There is much excellent detail in your original post regarding the mechanical aspects of the conversion. You say that you are connecting it to wires not rated for 130 amps. I would agree that in normal operation there is no likelihood of the wires being expected to carry any where close to this figure....however....and this was my point....while it may have a convenient form factor the potential output is not academic and needs to be taken into account if the conversion is done. Fitting a unit with such a huge potential output may be mechanically convenient but may not necessarily be electrically convenient. If a fault develops then the alternator will most certainly have the potential to overload the main wire leading to the battery with unfortunate results....it has no fuse and no fuse would provide sensible protection anyhow. I am certain you have taken account but others attempting this or similar conversions, especially if done to a car fitted with a dynamo, may not. I remain of the opinion that fitting such a unit may, in rare circumstances, lead to the possibility of a serious electrical fire unless sensible measures are also taken to upgrade wiring...that is my point.....and I have avoided any bold text

[MLBS3V12]

At the risk of pointing out the obvious, installing a 130 amp alternator seems unwise. Let's look at the possible demands. Headlights on full beam. 10 amps. Side/rear/no plate/instrument lights....say 5 amps. The brake lights are on..4amps. Indicators on... another 4 amps. The heater blower is on....say 10amps. Then engine cooling fan is on....another 10 amps....and you have the radio on max vol....say 3 amps.....that is 46 amps....and I am ridiculously pessimistic. Added to this the battery is flat and being charged....say 20 amps....we have got to a theoretical 66 amps....
A very unlikely set of circumstances. SO why are people fitting an alternator capable of supplying an extra 60 plus amps? If there is a battery fault or wiring fault from the alternator the cabling should be able to carry 130 amps....no e type loom is built to any where near that specification. A land rover is presumably wired to accept such an alternator and will probably have more On board electrical gadgets plus a tow bar and split charge circuit to charge a large leisure battery in a caravan. If you really must fit a huge alternator you must address the cabling too.....and the same goes for those converting from a dynamo to any alternator. Chances are dynamo wiring will not be up to the output from an alternator as most standard alternators today can produce 70 amps whereas your trusty dynamo will produce about 22 amps....which is quite sufficient for UK cars ....mine runs a dynamo with no problems....just my take....

to get the car safe then why not get a 70A fuse between the alternator and the rest of the circuit ?