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Generator vs altenator

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AUSMHLY

AUSMHLY

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64 BJ8 II

What's the take on changing from the generator to an alternator. Should that be a concern if I change to neg ground?

Will the generator be more reliable?
Will it do a better job keeping the battery charged?

Any links to how to do it, where to obtain the parts?

Thank you, Roger
 
I think the alternator will do the better job of charging the battery and will be easy if you switch to neg. ground. That being said, my generator in my ph 1 BJ8 works fine at charging the battery (current battery is 4 yrs old). For that matter, I see no advantage in switching to neg. ground either, unless you are adding a radio/cd player. In that case the addition is easier with neg ground. Otherwise, you must totally isolate the radio from ground, including speakers and antenna. That is not too difficult to accomplish though, which is what I did when I added my radio.
 
HI AUSMHLY, I do not recommend trying to isolate a radio which is designed for Neg GND in a POS GND car's electrical system. IMOP that is a potentialy costly melt down just waiting to happen.Converting to Negative ground will give you more options on alternators to use and the alternator is more reliable than the old Dynamo,plus it will maintain battery charging at idle and provide enhanced charging during night time driving.---Fwiw---Keoke
 
The alternator will be more reliable than the generator over the long haul but there's nothing wrong with a generator if you haven't added high-currant accessories like halogen headlamps. This always comes back to a debate between originality vs. reliability.

I am REALLY hoping the product on the link below becomes available in the U.S. at a reasonable price. At the moment it's about $800 imported to the U.S.

https://www.racemettleltd.co.uk/dyn.html
 
/ubbthreads/images/graemlins/savewave.gif HI DK, Yeah thats neat, but why should I pay almost $800.00 for a 5A up grade when I can go to the junk yard and get 80A for $15;00 and the best he can do on a small alternator is 55A .---Keoke- /ubbthreads/images/graemlins/crazyeyes.gif------OH! by the way Moss Europe is also selling them. /ubbthreads/images/graemlins/yesnod.gif
 
my dear friend keoke,weve wrestled with this one befor,thats why fuses/circut brakers etc are installed,anything you could add to the electrical interups of this vehicle would be far superior to what exists,you make it sound as if a dead short from pos. to neg would have a different result then a neg to a pos short,i believe this vehicle is an equal oppertunity polarity disaster!imop juice is juice! no matter what direction you think it travels in!by the way im gunna send you the master boot mounted battery cut off swith i just ripped out, that i know your so fond of! ha,ha darling! /ubbthreads/images/graemlins/yesnod.gif
 
No I think you mistook me. I simply meant that a NEG GND Alternator is much easier to source than a POS GND one. Similarly if you plan on adding other electric items they too will most likely be NEG GND compatible only with out fiddlin.As a matter of fact the DYNALITE and that vendors Alternators are only available in the NEG GND configuration too. Regarding the cut off switch I wil be out early every day awaiting its arrival.---Keoke-- /ubbthreads/images/graemlins/yesnod.gif- /ubbthreads/images/graemlins/laugh.gif PS: Be sure and include the bracket too!
 
keoke,o.k. now i understand what you ment,but who ya kiddin?we all know you dont get up much earlier that 1-2 oclock! /ubbthreads/images/graemlins/lol.gif
 
"The alternator will be more reliable than the generator over the long haul but there's nothing wrong with a generator if you haven't added high-currant accessories like halogen headlamps. This always comes back to a debate between originality vs. reliability."


That prompts another issue. Yes, I plan on installing PL700 headlights, which come with halogen bulbs.

If I stay with the generator, will that be a problem? /ubbthreads/images/graemlins/confused.gif Roger
 
[ QUOTE ]



That prompts another issue. Yes, I plan on installing PL700 headlights, which come with halogen bulbs.

If I stay with the generator, will that be a problem? /ubbthreads/images/graemlins/confused.gif Roger

[/ QUOTE ]

Yep Roger.---Keoke
 
Halogens and generators are not a happy mix. However, if you don't do much long distance night driving you'll be fine. (Search for other threads on the board about fitting relays to power your halogen lamps and protect your wiring/switches).

Keoke, I know Moss Europe is selling Dynalite. They will ship them to you in the U.S. That's where I came up with the nearly $800 price tag (delivered).

Why would anyone pay $800 for the Dynalite? I can't answer that. I want one, but not for a Healey, and not at that price. For the Mini, I'd like to have the reliable alternator and at 40Amps, the Dynalite is a step up from the 22Amp Lucas C40. Being packaged in a C40 case, the Dynalite would "look correct" in my engine bay.

As it is, I've got a big, reliable, Motorola alternator. It works a treat but it doesn't look right, it required I fabricate a custom coil mounting bracket, and it prevents me from running the original oil cooler supplied with my car. I've considered repackaging a $200 Denso racing alternator in a Lucas C40 housing but I really want to make up-close measurements of the Denso unit before committing to the purchase.
 
[ QUOTE ]
[ QUOTE ]



That prompts another issue. Yes, I plan on installing PL700 headlights, which come with halogen bulbs.

If I stay with the generator, will that be a problem? /ubbthreads/images/graemlins/confused.gif Roger

[/ QUOTE ]

Yep Roger.---Keoke

[/ QUOTE ]

Weren't the PL700's a period accessory? What exactly is the problem? Wires get too hot? Halogen bulbs don't like the lower current?

Cheers,
John
 
Looking forward to that answer too John.

So guys, with the halogen bulbs, if I change over to an alternator, should I still be concerned with the wires getting too hot? Roger
 
Yes, the halogen bulbs (being higher wattage) will draw more current through what is already too small guage wire. The alternator with greater charging output will keep the battery charged with the greater draw from the halogen headlights, but it won't protect the wiring from overheating. The fix is to run larger guage wire to the headlights. You can use the existing wire to control relays and the relays will actually turn on the headlights. Go to www.danielsternlighting.com/tech/relays/relays.html for instructions on how to upgrade your headlight circuit. You should be able to do this in about 2-3 hours.
BUT BACK TO THE ALTERNATOR/generator question. You will still be alright with a generator, even with halogens, if you don't drive a lot with your headlights on. While I don't have halogens, I do have two fog lights. Occasionally, I drive with both the fog and headlights on and the generator still charges the battery.
FWIW, I would install the halogen headlights with the P700's first with the relay system, before I consider the switch to neg ground & installing an alternator. If you don't experience charging problems (the little red light in the tach will tell you), I would leave the car as original with the generator and pos. ground.
Why do the wires get to hot? Well, again to0 light a guage wire, but generally bad connections (the bullett connectors get dirty and corroded), usually the ground connections. Whether you go to halogens or not (regular bulbs are available too), or add relays or not, it would be a good idea to check, clean, replace if necessary, the bullet connectors.
 
HI DK, You can almost double that 22A capacity by going to a C42 Dynamo_On the other hand, being sneaky I also want to package an alternator inside a standard dynamo case. So I will share with you a tip that LIN passed on to me some time ago.There exists on some of the import fork lifts a very small high capacity alternator which might work- reuiring a minimum of machine work to fit it. I have been busy with other things and have not had time to locate that Item as yet, so lets go see if we can find one small enough.---Fwiw---Keoke
 
HI John, I had to go read the article. While it is basically good. I would take exception to two of the statements: 1] 100 watts disapated in the lighting switch, If so the plastic handle would melt and drip off. Further, if 1 ohm of resistance were present in the switch as stated and you have 10A of current flow. there would be not less than 10 volts drop across the switch alone ,doubt if the lamps would illuminate on what was left. 2] Adding GND return wires- if we postulate that is the only return path for the circuit you now have at least twice the resistance you had in the chassis ground configuration.You could if you wanted to beef up the existing GND wire to the chassis -but why? since resistance is directly proportional to length and inversly proportional to cross sectional area,there is no reasonable wire size that can compete with chassis GND return path and the small resistance of the harness gnd wire in a sea of nearly none,the chassis, is more than comphensated for.On the other hand, keeping the wire circuit interfaces clean is a valid argument but not a daily chore.---Fwiw---Keoke


PS. OH! do install relays to operate all the Head/ Driving lights you install on your vehicle. /ubbthreads/images/graemlins/yesnod.gif
 
Keoke, I have pursued some of the forklift/industrial-truck alternators. I even bought a rebuilt one I thought would work. So far they all have stators larger than the OD of the C40 generator case. I'm not giving up though. I'll keep looking in my spare time. Like you, I have other things I'm working on at the moment. The alternator conversion is a long-term project.
 
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