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Discussion Starter #1
Finally enough snow gone to drive the GTV. Yesterday, the ignition light stayed on for the drive home. I am wondering how to check the generator and the regulator for charge. I know the recomendation will be to replace with an alternator but I would prefer to stay original.
Thanks in advance.
 

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How many volts do you at the battery when she is running? All the connections tight etc?
 

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Might wanna check that the drive belt is tight, not slipping, dry and not glazed, cracked, or wet from a puddle or something before getting all up in a charging system swap~out.

S'not even beyond the realm of possibilites that the pulley nut on the generator has loosened and letting the pulley free spin a little bit.

May we presume that you double and triple checked all connections associated with the generator and regulator, and also including the battery terminals (tightened down, or just thumped on with the palm of your hand?) and ground strap (tight, clean contact, actually affixed to engine and chassis?)
 

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Discussion Starter #5
Might wanna check that the drive belt is tight, not slipping, dry and not glazed, cracked, or wet from a puddle or something before getting all up in a charging system swap~out.

S'not even beyond the realm of possibilites that the pulley nut on the generator has loosened and letting the pulley free spin a little bit.

May we presume that you double and triple checked all connections associated with the generator and regulator, and also including the battery terminals (tightened down, or just thumped on with the palm of your hand?) and ground strap (tight, clean contact, actually affixed to engine and chassis?)
Hi Darren Everything seems ok , I am just not sure how to check the ouput of the gen and if the regulator is kaput!
Brian
 

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13 volts is a bit low, should be over 13.5 to keep up with draw. If you have a local shop that rebuilds these should be easy to rebuild or you can check the brushes etc at home. That is a pretty common point of wear - others will likely have more specific info.
 

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Discussion Starter #7
checked the voltage from the gen to the regulator 7 - 8 volts:( no change with more rpm :(:(
Brian
 

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Rebuild time - shouldn't be a big deal.
 

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Hi again Ok managed to get the generator rebuilt and had the regulator tested at the same time and it needed replacing. So installed both and when I went to connect the battery, big spark. Ignition was off and everything was wired as before. Does the gen need to be polarized and if so, how?
Help please
Brian
 

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Uh oh. Was the ignition key in an on/run position?
 

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Sorry Brian - that was pre-coffee. There had to be some load on the system for the spark to occur, if there wasn't a draw then no flow through the terminals.

Polarity is fairly straight forward to address. This video is worth watching - but please be aware that while the principals should be correct this is for British cars.

 

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Hi again Ok managed to get the generator rebuilt and had the regulator tested at the same time and it needed replacing. So installed both and when I went to connect the battery, big spark. Ignition was off and everything was wired as before. Does the gen need to be polarized and if so, how?
Yes your generator does need to be polarized. But I'm pretty confident that the fact that this hasn't been done yet is NOT the cause of that big spark. I can't explain what is the cause - I would start by asking the people who tested and rebuilt your generator and regulator if they can explain it. My guess is that 1) they'll ask if everything was re-connected properly, and 2) they will want to re-test the two components.
 

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That is pretty odd Jay - I've never seen one generate a spark before, have you?
 

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That is pretty odd Jay - I've never seen one generate a spark before, have you?
I'm sorry, I didn't understand your question. Not sure what "one" refers to. Did you mean: "have I seen a newly rebuilt generator/regulator generate a spark before"? Well honestly, no.

While I'm no expert on generators, I am guessing that MRTR2 either has:

- A faulty generator or regulator that is producing the short. Yes, newly rebuilt parts can be bad "out of the box".

- A short somewhere else in the car's electrical system. It is possible that there was never anything wrong with his charging system - that the persistent warning light was due to a short somewhere else, and not a failed generator.

My next step would be to disconnect the generator/alternator, and see if the spark still happens when the battery is re-connected. That would help to distinguish between the two broad possibilities I suggested above. Another interesting diagnostic would be to put an ammeter between the battery "+" terminal and the battery wire - how many amps does this short involve? "big spark" implies a problem, but knowing if it's a 2a or 20a problem would tell us a lot more.
 

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Hi Jay - sorry for the poorly formed question. What I was trying (grin) to comment on was that I have never seen a case of simply reconnecting a generator produce that behavior. That it did seems to suggest that there was a problem in the rebuild, either with how it was done or the parts.

Brian - is the shop local and can you bring it back to have them check it out?
 

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Discussion Starter #17
tdskip and Jay thanks for your input. I got to play a bit yesterday morning but then got involved with a turkey feast. I did go back to my TR2 manual for test info on a generator. They said to run a test wire between the 2 terminals on the gen and test between them and ground. With the car running, I was getting very low voltage. 1 to3.5 on revs. Repair man is local and I will return the gen to him. If the gen was not polarized, could it ground and short through the generator at power hook up? Or only cause issues when the car was running? Jay good idea to isolate the spark issue.
When i put the old regulator back in, it did not spark. I had the cover off the regulator and the points were on rapid fire mode. Less than a second on off.
I did test for amps on the B+ terminal and bat. wire with no amps. So I think the original reg. is toast. I did check continuity on both leads from the gen and they were ok although all wires are very brittle. I will check with my rebuild guy today to confirm what he had for volts. Tonight I will put the new reg in and try to isolate the spark as Jay sugested. Gen or Reg. And probably return the gen tto have it re checked tomorrow. I have learned a few things. Like why GTV owners put the battery in the trunk and exhaust manifolds are HOT when the car has been idling for 5 minutes. I am getting pretty good at getting that gen out.:)
Thanks for your help guys.
Brian
 

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If the gen was not polarized, could it ground and short through the generator at power hook up?
Brian:

I don't know the answer to that. I suppose it's possible that a yet-to-be polarized generator might draw a small load - say an amp or so. I really doubt it would draw several amps, as people hook up their new generators, and then casually polarize them without having wires melt. That's why I'd like to know how much current that "big spark" represents.

I'm afraid I'm one of those people you reffered to in your initial post - the kind who just pull the generator/alternators out of their Giulias and substitute alternators.
 

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Discussion Starter #19
Brian:

I don't know the answer to that. I suppose it's possible that a yet-to-be polarized generator might draw a small load - say an amp or so. I really doubt it would draw several amps, as people hook up their new generators, and then casually polarize them without having wires melt. That's why I'd like to know how much current that "big spark" represents.

I'm afraid I'm one of those people you reffered to in your initial post - the kind who just pull the generator/alternators out of their Giulias and substitute alternators.
Hi Jay It was a pretty good spark. Kind of like touching the mig wire in at a medium power setting. I will see what I can find out tonight. Talked to the rebuilder this am and he said bring it back with the new reg. and he will check both.
I agree changing the gen to an alternator is the logical smart decision.... I'm just not that smart.:eek:
Thanks for the help
Brian
 

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Discussion Starter #20
tdskip, Jay and any other electrical wiz types. So far not so good.
Polarized the generator. Replaced a couple of slightly suspect conectors.
hooked everything up with the old regulator in place. No spark. Replaced the old reg with the new one and conected the wires with bat lead off. As soon as I touched the bat lead to the post, I was welding and I could hear the regulator click (more like a klunk). Disconect the B+ (red) wire on regulator
and hook up the bat. no problem. As soon as I touched the red to B+ spark.
Disconect the large gen lead (greeny blue) from the reg and conect the red to B+ no spark. As soon as I touched the gen lead to the regulator spark.:(
Help!
Brian
 
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