Overcharging and battery draw

[readoaksigns]

Hi,

I replaced my alternator recently because my system was not charging. Now its overcharging. I'm looking at 17V which is way too high. I don't have the external regulator. I also don't have a choke heater. My choke is manual. My car is 1973 620 truck with L16 engine. Also there is a draw on the alternator around 3Amps. When I disconnect little cables it goes away. I saw similar topics but they mentioned rewiring stuff because of the choke heater. Since I don't have it I presume my issue is a little different. Any pointers would be much appreciated. Please let me know if you need any pictures or additional info. I'll do my best. Thank you!

[datzenmike]

Replacing parts gets expensive when the replaced part does not fix the problem. Find the problem, fix it once. As it wasn't charging and now is over charging you've introduced a new problem, likely the alternator. Hopefully it wasn't a '73 alternator. Take it back. These cheap rebuilt alternators or 're-pops' from China are often 'bad in the box' .

 

Did you do the conversion to internal regulated alternator? There is also a choke heater relay that needs to be removed as the conversion wires it permanently ON. The little coil inside the relay is still drawing some current.

 

Put the year of your 620 in you profile and your state. There were many many differences in the 620 over the 7 years and it will reduce you answering questions. Different states have different emissions parts. You know where Petaluma is, I don't.

[readoaksigns]

Thanks for your reply. It was already converted to internal. I don't have a choke heater. Truck is from 1973. I'll add it to my profile though like you suggest. Petaluma is in California. Now we both know 😄

[datzenmike]

Yes, you said no choke but there is a relay that has to be deleted. it's not powering the choke heater but it's on all the time. I did this to my car and by Monday morning the battery is low, a 3 day weekend and you need a boost. The relay is on the passenfer side inner fender

[Crashtd420]

8 hours ago, readoaksigns said:

Thanks for your reply. It was already converted to internal. I don't have a choke heater. Truck is from 1973. I'll add it to my profile though like you suggest. Petaluma is in California. Now we both know 😄

What was the replacement alternator?

Did you ask for one for a 73?

Because it sounds like you replaced it with an externally regulated alternator..

[datzenmike]

Once converted to internal regulated an external will no longer work properly. Never heard of them over charging so that likely is just a bad replacement.

[banzai510(hainz)]

If your getting 17 volts maybe its a unregulated 17 volts. This means the alternator is working and the volt reg or not one is causing this.

 

On my 521 I run a cig lighter volt meter. Usually I had a solid state external volt reg and they can pop and I would see my volter go past 15 and put everything on and still overvolts. I put another volt reg in then works again

 

Now if your carb dont have a electric choke and the wire is back on the fire wall. doesnt mean that is still not working. as there is a relay to power this and a modification needs to be done if one put a newer later model alternator in. But sonce Im not a MIND READER and privous owner of this truck Im only guessing.

You need to take photos of back the alternator and where the volt reg is or isnt.  If modified there are 2 jumper wires added where the external volt reg should be on the wire harness. then YOU had a IR Internal volt reg alt in there . Hopefullyou ordered the same type of alternator as the volt reg is in the alternator

 

if the external volt reg is still there then get a japan made volt regulator an hope that fixes it

 

battery drain? watch the first min and do this test

https://video.search.yahoo.com/search/video?fr=yfp-t&p=scotty+kilmer+battery+drain#id=1&vid=418de20d5f3335af5d80b045562c43ac&action=click

 

 

 

this is a simple fix but            you swapped to many parts for me to keep up. if there was a battery drain before you swapped the alternator this be nice to know. 

I always ck the fuses and seating of them in case loose connection where maybe the alt wasnt getting the 12volt to charge the windings in the alter thus no charging

Edited February 4 by banzai510(hainz)

[readoaksigns]

Like I said I swapped only the alternator. Is this a lot of parts? And it was direct replacement of the one I had before. The alternator I got is internally regulated. My car never had external regulator since I got it. Drain wasn't there . It showed up after I replaced the alternator. 

[banzai510(hainz)]

what year alt you ordered for this truck?

 

 

alt with F and N fot T connector require a External Volt Reg 70-77 620

alt with L and S are have the volt reg inside alternator 78 and up 620

Edited February 4 by banzai510(hainz)

[readoaksigns]

1973

[banzai510(hainz)]

Did somebody put this adapter in the engine side harness or a version of this with 2 wires.??? If you dont have a external volt reg. and you went to the part store and put a 73 alternator in there then your eletrical will over volt, Cause that alternator dont have a built in volt reg.

 

take photos if you have to

[readoaksigns]

16 minutes ago, banzai510(hainz) said:

what year alt you ordered for this truck?

 

 

alt with F and N fot T connector require a External Volt Reg 70-77 620

alt with L and S are have the volt reg inside alternator 78 and up 620

The one I have is 10000000% internally regulated. I replaced it on warranty and will try again later today. 

[banzai510(hainz)]

32 minutes ago, banzai510(hainz) said:

what year alt you ordered for this truck?

Well I asked what year ALT you ordered for the truck you said 73. So I assumed its NOT regulated Alternator

[datzenmike]

2 hours ago, readoaksigns said:

Like I said I swapped only the alternator. Is this a lot of parts? And it was direct replacement of the one I had before. The alternator I got is internally regulated. My car never had external regulator since I got it. Drain wasn't there . It showed up after I replaced the alternator. 

 

1 hour ago, readoaksigns said:

1973

 

These two post do not agree.

 

'73 through '77 620 alternators were externally regulated. The '78-'79 were internally regulated.

 

If your '73  was converted to an internally regulated alternator why would you put an externally regulated alternator back in it??????

 

 

21 hours ago, datzenmike said:

Replacing parts gets expensive when the replaced part does not fix the problem. Find the problem, fix it once. As it wasn't charging and now is over charging you've introduced a new problem, likely the alternator. Hopefully it wasn't a '73 alternator. Take it back. These cheap rebuilt alternators or 're-pops' from China are often 'bad in the box' .

 

Did you do the conversion to internal regulated alternator? There is also a choke heater relay that needs to be removed as the conversion wires it permanently ON. The little coil inside the relay is still drawing some current.

 

Put the year of your 620 in you profile and your state. There were many many differences in the 620 over the 7 years and it will reduce you answering questions. Different states have different emissions parts. You know where Petaluma is, I don't.

 

 

Take it back it's the wrong year. Get a '78 or '79 internally regulated alternator.

[readoaksigns]

I have INTERNALLY regulated alternator. I can't explain it any clearer. I went to the store. Showed my old one. Told them it's from my 1973 Datsun. They brought me the exact replacement. What happened is they probably checked numbers and gave me what I brought to them. 
To sum up:

- after replacing internally regulated alternator that was toasted with another internally regulated alternator I see overcharging and 3Amp draw on the alternator
- since I owned the car I never had external regulator
- before old alternator went bad there was no draw

After everything I read here it looks like I had bad luck and got broken alternator. Hopefully the one they gave me on warranty is good. I'll check tonight.
 

[datzenmike]

You can see how telling them it was a '73 could lead to them giving you a '73 external regulated alternator right? Outwardly they all look the same.

[datzenmike]

 

You were asked what year you ordered...

 

3 hours ago, banzai510(hainz) said:

what year alt you ordered for this truck?

 

 

 

 

You said '73

 

3 hours ago, readoaksigns said:

1973

 

 

See the confusion????

[datzenmike]

Again, take it back tell them it's no good. Be sure to get a '78 or '79 internally regulated one.

[readoaksigns]

I already returned it and got a new one. I returned the one that was overcharging. I got new one this morning and I'm about to test it tonight. It is internally regulated. 

[banzai510(hainz)]

waiting for the results

Edited February 5 by banzai510(hainz)

[datzenmike]

Did this resolve you over charging problems??????? If it did say so, so othes reading this with a similar problem can learn from it.

 

Maybe post a picture of where your regulator was just behind the battery.