Alfa Romeo Forums banner

1 - 20 of 23 Posts

·
Registered
Joined
·
360 Posts
Discussion Starter #1
Act I

About a week ago I noticed that the gen light on my 69 Spider Jr. was flashing every couple of seconds while driving at hiway speeds. I looked for loose wires or a fuse and didn't find anything wrong.

Act II

Before I could do any more testing the gen light stopped coming on altogether. At the same time I also notices that intrument lights for the tach, same module where the gen light is, were both out but they may have been out for awhile since I rarely drive the car at night.

Act III

This weekend I got out the voltmeter and found that the generator appeared to be working. Voltage went up with the revs and I saw readings as high as 16v (too high?). I pulled the tach out of the dash looking for a bad ground but it apparently grounds through the tach chassis to the dash. I did register voltage from the gen light wire with the engine off. I also found out that only one of the intrument bulbs was burned out.

So how do I end this mystery? Is it a bad regulator or gremlins in the dash or did the butler do it?

Anybody know a source for new intsrument bulbs?

Thanks
 

·
Trained (ex)Professional, , 1953-2018 RIP,
Joined
·
16,232 Posts
If I'm not mistaken, your '69 should have an alternator, not a generator (even though the dash light says 'GENERAT.') If your voltage regulator looks like the one in the pic, you have an alternator. In either case, 16v is WAY too high. Try disconnecting the regulator and recheck the charging voltage. If the voltage does NOT rise when the engine is revved up, the alt is probably OK but the reg needs to be replaced.
The GEN light is grounded thru the green wire that goes to the D+ terminal at either the voltage reg or the alt. The pink wire on the light is switched power thru fuse #6.
Instrument lightbulb info to follow.
 

Attachments

·
Registered
Joined
·
5,799 Posts
Hi,

Your car has a generator. It's a piece of crap! Do what I did and replace your generator with an AC/Delco (GM) alternator (with internal voltage regulator) from a '70s Chevy (about $70 from any auto parts store). You will have to fabricate a bracket and put in some home-made bolt spacers, but it's probably the best modification I have ever done to mine!

I can send you the plans if you like.

By the way, Mitch...that's a VERY rare car that you have there! As far as I know (I've done a lot of research too!), there are only about 60 roundtail 1300 Juniors left worldwide! Is yours a Canadian model (english gauges)?

Cheers,
 

·
Trained (ex)Professional, , 1953-2018 RIP,
Joined
·
16,232 Posts
Guess I'm mistaken. So what year/model/engine size did Alfa switch to alternators? Both my 68 1750 GTVs have alts.
 

·
Registered
Joined
·
2,067 Posts
Are the older generators really that bad?? I have one in my '67 GTV and it works fine as far as I can tell. I have yet to break out the engine analyzer though. Will it tell me what I need to know about the charging system?
 

·
Registered
Joined
·
5,799 Posts
Yup...they really ARE bad! That's why EVERYBODY switched to alternators! The generator will charge your battery pretty well, provided you're not using lights, windshield wipers, heater fan or (heaven forbid!) a radio!

If you want a 100 point car, you probably don't drive it much...if you want to use your car in weather and at night...get an alternator!

Cheers,
 

·
Trained (ex)Professional, , 1953-2018 RIP,
Joined
·
16,232 Posts
67GTV said:
Are the older generators really that bad??
Yes, they are. They put out virtually nothing at idle and will fly apart at half the speed that an alternator will. Then there's brushes to change, commutators to dress and undercut, cutout relay in the regulator goes bad, polarizing before it'll charge.....

But it IS original!
 

·
Registered
Joined
·
5,799 Posts
Oh! I just figured it out! I had the battery in wrong! I switched the leads and now everything isn't from 'Bizarro Alfa World' anymore!:D

Seriously though...I sure am glad that this isn't the BritishBB.com, or the electrical section would be chock-full of troubles! With Alfas, almost all electrical problems can be attributed to a bad ground or corroded and dirty switch gear and terminals.

Cheers,
 

·
Registered
Joined
·
2,067 Posts
Hmmm, I don't know. I have been ignoring all discussions about switching to alternators because my generator seems to work so well. Now you guys are making me nervous.

I upgraded my lights to H4 bulbs. They are much brighter than the sealed beams they replaced. I have an old AM/FM radio that does not draw much current. I rarely use my wipers and never use the heater fan. For some reason I always have warm air coming in through the 'system', but that's a request for advice for another day.

My generator light only comes on at idle, although the most load I'm putting on the generator at one time would be my lights and the radio. I'll have to try using all these devices at the same time.

I just bought a NOS AM/FM cassette deck with adjustable shafts that'll fit in my dash without having to make any cuts. Perhaps I will need to look into switching to an alternator after the stereo installation. Although it is rated at a paltry 25w peak power.

With the suggestions of switching to a new Delco alternator, what about using a Bosch alternator off a 2-liter Alfa engine? I have one that I was saving for the 2-liter transplant. Would I be looking at making bracket/spacer modifications? I do have the alternator bracket. And what about the fan belt? Are alternator belts longer or shorter than generator belts?
 

·
Registered
Joined
·
5,799 Posts
Honestly Kai and all, I really tried to live with my generator. I figured if they lived with it in '69, so could I. However, in '69 the 'genny' was pushing 'juice' through new wires, etc.

Unless you plan on using your car only in the daytime in dry weather, it is worth changing to an alternator.

Now, if I had a trailer queen...it would be 100% 'originale'!

The Alfa alternator works fine, but the AC/Delco internal voltage regulator makes this a really easy and trouble-free swap. I chose the latter, YMMV.

Cheers,
 

·
Registered
Joined
·
360 Posts
Discussion Starter #15
Hi Guys,

I'd talked with you (Alex) before about your Spider Jr. Mine is a euro model with guages in Italian metrics. How it got to Denver I'll never know (shaking ashes off of Groucho's cigar) but its a barrel of fun.

I originally replaced the brushes on the generator when I first got the car about 6 years ago and haven't had to mess with it since. I do mostly drive it on sunny days and the radio isn't worth playing. I've also got an Optima battery which I highly reccomend. I'm planning to update to an alternator but not until the old one fails. Right now its still charging okay, according to my voltmeter, its the dash circuit that's the problem and wouldn't be solved by an alternator, though a new regulator might do the trick.

Kai, I'd appreciate if you could check the output from your generator. I don't think it should go as high as 16v but I don't know for sure.

Thanks
 

·
Trained (ex)Professional, , 1953-2018 RIP,
Joined
·
16,232 Posts
I know this thread is getting a little bit away from MitchW's original question (sorry), but to answer Kai's question, the current draw of a period radio can be measure in milliamps and the headlights pull maybe 8 amps total on highbeam. The stock generator can easily keep up with this if all is normal with the system. However, if one were to add a sound system that is capable of breaking the neighbors windows or headlights more suited to jet aircraft, the genny's gotta go.
For anything in between, my thought would be to go with a 2l or newer Bosch alternator; higher output than the 35 amp 1750 version and has an internal regulator. And it would look more like it belongs there than a GM unit would. Then again, you can get a GM 7127-12 53 amp alt for about 30 bux.
 

·
Trained (ex)Professional, , 1953-2018 RIP,
Joined
·
16,232 Posts
MitchW,
I posted some info on instrument bulbs in the electrical forum under the thread 'instrument bulbs'. Hope you find it useful.
 

·
Registered
Joined
·
2,067 Posts
Mitch I apologize for highjacking your thread. I'll break out the engine analyzer this weekend and have a go at it. Never used one before.

Thanks for the input Jim and Alex. I'll keep your advice in mind. The stereo I purchased will be the only addition to my sound system for now. I may replace the speakers, two 6x9's and two 5-1/4's, depending how they sound with the new stereo. But that's about it.

Alex, I'd be interested in taking a look at your alternator swap plans though.

Thanks!
 

·
Registered
Joined
·
360 Posts
Discussion Starter #20
Thanks guys,

Asking the questions sometimes helps me come up with my own answers, sometimes. I think I'll need to take another look at the indicator circuit and understand how it actually works.
 
1 - 20 of 23 Posts
Top