Replacing the stock generator with an alternator

[matpoli]

Hey guys I have a series 2 2.25 petrol and the STD generator just can't handle my new headlights and spotlights without draining the battery. Does anyone know where I can get a kit including bracket bolts etc to fit an alternator please??

[Blknight.aus]

is it a generator proper or an alternator?

I'm happy to see about coming up with one for a swap if yours is complete and workable.

[matpoli]

It's a proper generator, long black thing looks like a kingswood starter motor lol. My old man thinks I'm nuts but I need more juice. I'll take some pics tonight but I don't want to fabricate anything I just want a nice bolt in job so I can't promise a swap at this stage plus I find it hard to let go ha ha.

[Blknight.aus]

pretty sure setting up an alternator to go onto a 2.25 isnt something thats going to cause me any heartache.

[matpoli]

Here is a pic.

I have also heard that I might be able to get an auto electrician to fiddle with the regulator to extract more juice from the generator but I'm not sure really.

Kind of thinking about it atm and looking for more info.

[Blknight.aus]

from memory they are good for 20-25A

[JDNSW]

The problem with generators compared to alternators is that they need a lot higher engine rpm to produce their rated current, mainly because they need to have a larger pulley to prevent exceeding their safe rpm at high engine speeds. This means that they you will sometimes find the battery going flat if you do only night driving at low speeds even with the standard lights. Fiddling with the regulator to increase the current regulator setting will not help this problem at all. (The advantage of the generator is that it will start generating with a completely dead battery, allowing the vehicle to tow or roll start in this circumstance, where an alternator cannot start generating without a battery in reasonable condition - I have struck the situation where an engine can be crank started but the alternator will not charge because the exciting voltage is too low.)

The simplest way of fitting an alternator is to get the alternator and brackets from a Series 3 and fit that. Bolt on job and wiring has only trivial changes, even though the alternator is not perhaps the best you could get. Note however, if it is a pre-1967 2a with positive earth, the polarity must be changed to negative earth. Especially if fitting a larger alternator, on this pre-1967 setup the dash mounted ammeter means a long feed from the alternator to the battery and a voltage drop that will reduce the maximum charging current and may lead to overheating wiring. Plus the ammeter will be overscaling and may be damaged.

John

P.S. I'm inclined to agree with your old man - fit headlight relays before fitting higher wattage lights or extra lights - if you don't, you won't get a lot more light and will almost certainly damage the headlight switch. But the alternator will be a lot more reliable than the generator!

[matpoli]

Thx heaps John. So now I am contemplating fitting relays to my high and low beam circuits because I did fit some narva 72040 h4 lights in place if my originals? Will this act in it's self stop the drain on my battery when I turn the headlights on because ATM when I turn my lights on at night the charge indicator reads 0 on the 55w low beam and when I turn on the 100w high beam and spot lights it goes into negative. Will the relays relieve the drain on the 55w at the least?

[matpoli]

Hey guys I just want to send a big thank you to Jonh for solving my problem and saving me a lot of cash. I fitted relays to my high and low beams and there is relatively no draw what so ever on the amp meter and when I turn on my high beam (100w) and my 2 hella spotlights (100w) also, the amp meter actually shows the same amount of charge as when I'm doing daylight driving - no draw what so ever.

So basically I have no need to replace my generator but I have no seen a good reason to justify a whole new wiring loom eventually. Now it's only my indicator and stop lights that show a draw on the amp meter but as they are only on when I need them I can put that job off for a while.

Oh and sorry blacknight but I'll be keeping the old geny as there's life in it yet :)

[drifter]

Hey guys I just want to send a big thank you to Jonh for solving my problem and saving me a lot of cash. I fitted relays to my high and low beams and there is relatively no draw what so ever on the amp meter and when I turn on my high beam (100w) and my 2 hella spotlights (100w) also, the amp meter actually shows the same amount of charge as when I'm doing daylight driving - no draw what so ever.

So basically I have no need to replace my generator but I have no seen a good reason to justify a whole new wiring loom eventually. Now it's only my indicator and stop lights that show a draw on the amp meter but as they are only on when I need them I can put that job off for a while.

Oh and sorry blacknight but I'll be keeping the old geny as there's life in it yet :)

While your lights will be brighter and your light switch has less chance of burning out, you have only masked the problem.

Your lights, when on, will still draw the same amount of current from the battery. Your generator will still try, valiantly, to charge the battery.

All you are showing on your ammeter is the current draw for the circuits that flow through the ammeter. Anything wired outside of that will still cause your battery to discharge.

If driving long distances at night, especially using the spot/driving lights, your battery will still go flat.

With those spots, you really need to be able to provide a lot more charge than the generator can generate to keep that battery charged.

That is why many of us have converted to alternators.

John was suggesting that, by taking the power directly to the lights, via a relay, that your lights will be brighter - possibly eliminating the need for an alternator and the spots.

...
P.S. I'm inclined to agree with your old man - fit headlight relays before fitting higher wattage lights or extra lights - if you don't, you won't get a lot more light and will almost certainly damage the headlight switch. But the alternator will be a lot more reliable than the generator!

[drifter]

from memory they are good for 20-25A
One light @ 100W = 8.33A

2 headlights @ 100W each on full = 16.66A

Add 2 spots @ 100W each - another 16.66A

That's 32.32 A

More than the generator can supply

And that's before you count normal running requirements.

You are pulling power out of the battery faster than the generator can replace it.

[JDNSW]

I would look at fitting lower wattage bulbs to both the main headlights and spots - 55/55 and 55w. Believe it or not, your eyes' response to light is logarithmic. That is, assuming that the 55w lights produce half the brightness of the 100s, the difference in brightness will be just perceptible, not halved. In practice, the difference will be even less, because the voltage drop, even with relays, will be less with the lower current draw.

John

[Bigbjorn]

JD, I well remember long night drives with generator equipped vehicles, a lot of them 6 volt, when I lived in Winton long ago. If you had a long drive home at night say from Longreach or Boulia, Kynuna, Muttaburra, you needed to remember to hook up the charger when you got home as particularly with the 6 v. vehicles you might not get a start in the morning. My dad always put a two pin socket somewhere handy on the outside of all the cars and trucks so you drive into the big shed and lift the charger lead off its hook on the wall and plug in. We used to fit 75 watt sealed beams into all the 12 v. vehicles. These were the hot property of the time and long night drives on high beam really tried out those old generator systems. I had an Austin for a while with these installed and two Lucas 7" long range driving lights which I think were 60 watts. Prolonged use of all these used to overtake the generator and after a while I would notice the lights getting progressively dimmer so I would switch off the Lucas pair for a while to let the system catch up.

[JDNSW]

Brian,
Yes, although I never had enough money to go overboard on lights like that, and the only 6v vehicles I have ever owned were a Model T and a VW (as an aside I find it remarkable that most US vehicles stuck with 6v for decades after most of the rest of the world changed to 12v). When I was working in the Longreach area in the early sixties I had a single Lucas driving light that greatly improved vision, without overloading the generator like two might have. Probably never strictly legal to only have one, but nobody ever queried it!

John

[Bigbjorn]

John, I wouldn't have bought them as a single new Lucas Flamethrower was at least a week's pay for an apprentice. I would have been a third year then. I probably got them in exchange for goods or services.

A Delco technical rep. once told me that the Yanks stuck with 6 volts so long because the bulbs are mechanically stronger and Yanks had a lot of bad roads in rural areas particularly in the snow belt where freezing and thawing causes humps and waves and breaks up pavement. Semi trailers on 24 volt prime movers were almost always 12 volt until LED's took over in recent years. Same reason, empty running at night shook the filaments to failure.

[matpoli]

Ah ok well it's looks like I fooled the ammeter and myself damn it.

I will have to go down the alternator option then, besides trying to find a series 3 alternator and bracket, can anyone suggest another type, maybe newer one with the regulator onboard??

I have a friend that may be able to get one for me brand new and pretty cheap so a current one would be possible.

Also I heard that the old holden red motor alternator bracket and alternators may do the trick, can anyone confirm this please?

[drifter]

Ah ok well it's looks like I fooled the ammeter and myself damn it.

I will have to go down the alternator option then, besides trying to find a series 3 alternator and bracket, can anyone suggest another type, maybe newer one with the regulator onboard??

I have a friend that may be able to get one for me brand new and pretty cheap so a current one would be possible.

Also I heard that the old holden red motor alternator bracket and alternators may do the trick, can anyone confirm this please?

I found a crowd on eBay that had a 'Lucas equivalent' 70A alternator - regulator built in.

The bottom (hinge) mount was fine but the top sliding mount wasn't too flash - so I used a red Holden alternator mount for that. Worked perfectly.

I changed the fan belt to a Bosch 11A1065 that fitted perfectly and I was up and running.

Mind you, I didn't have to change anything on the firewall mounted voltage regulator as all that had been removed when I rewired the car. If you dig around a bit, you will find a 'mod' that lets you bypass that regulator.

[matpoli]

Hey drifter,

When you changed to the alternator did it line up with the fan belt pulley on the engine and did you have to modify the Holden bracket at all?

I found this alternator which is an 85 amp Holden one so I'm hoping it will fit.

CoolDrive - ALT 12V 85A UNIVERSAL BOSCH (http://ishop2.cooldrive.com.au/products/BXU1285A)

Thanks in advance for anymore advice you may have.

[drifter]

This is the one I got:

LUCAS 12Volt 65Amp (Twin Leg Mtg) - GotyaParts (http://gotyaparts.com/product.php?id_product=65)

only I got it from Ashdown Ingram and paid a lot more than that for it.

If you are using the standard generator lower mount you need, from memory, 88mm across the bottom.

I took the pulley off (it is actually two 'bent' washers) and removed the spacers behind it and it lined up just fine.

Edit: here are some pics

https://www.aulro.com/afvb/images/imported/2012/01/92.jpg

https://www.aulro.com/afvb/images/imported/2012/01/93.jpg

https://www.aulro.com/afvb/images/imported/2012/01/94.jpg

https://www.aulro.com/afvb/images/imported/2012/01/95.jpg