Guest bigtoyzII Posted May 30, 2012 Share Posted May 30, 2012 I have gotten my 1937 Packard 120 out for summer use and noticed that the amp gauge is buried on the +30 side. When first started the gauge starts out to the + side of 0 but soon gets to +30 and bounces higher when I rev the engine. It has a 2 brush Delco #2794 generator and a Autolite RD4001A 25 amp regulator. Shouldn't it just stay to the + side of 0? Are the regulator points sticking or do I have the wrong components? I have never noticed it before but I just installed a new 6V battery after winter storage. Do I need to re polarize the regulator because of installing a new battery? Any suggestions where to start?Thank you Link to comment Share on other sites More sharing options...
West Peterson Posted May 30, 2012 Share Posted May 30, 2012 Doesn't sound like it's a generator problem as you wrote in your title line. I think you're correct in later stating that it's probably a regulator problem. Check to see if the points are stuck. Clean them. Is the regulator new, or NOS. If it's a driver, I recommend getting a new regulator vs NOS. They're available through CarQuest or Napa, probably others as well. Not sure what the correct one would be for your car, but the cost is around $50-60.There's also some way of adjusting the regulated output, but I'm not well versed in that. I'm sure someone else will chime in with more technical ways of fixing this for you.Don't drive it too much if it's charging that high, though, or you'll burn out your generator. Link to comment Share on other sites More sharing options...
Guest bigtoyzII Posted May 30, 2012 Share Posted May 30, 2012 Your right and thank you West. I don't think it is a generator problem as much as I am starting to think it is regulator. I am going to see if I can get the cap off now to see if the points are stuck. In the mean time I have called local parts stores and gave them the autolite regulator #RD 4001A and the can't cross reference it. I am hoping to find out if this is the correct regulator for the generator and what replacement regulator will work. I still want to replace it for reliablity. Anyone have suggestions for a replacemnt #?Thank you Link to comment Share on other sites More sharing options...
West Peterson Posted May 30, 2012 Share Posted May 30, 2012 I'm trying to find the correct replacement number for you. The one you have sounds correct, but I don't know for sure. 25 amps sounds about right. Mine is 35-40 amps, but then, I have more electricity running through my car, plus factory air. Link to comment Share on other sites More sharing options...
West Peterson Posted May 30, 2012 Share Posted May 30, 2012 I got the right person on the line right now. Evidently it's not an easy answer. Both the generator and the regulator would probably have been the same brand from the factory. They used both Delco and Autolite. Might be after lunch time for an answer for you. Link to comment Share on other sites More sharing options...
Guest bigtoyzII Posted May 30, 2012 Share Posted May 30, 2012 I just had the cap off and both contacts look pretty good. As I would open one set, the amps would drop to - and the motor ran with less drag. When realeased, it would go back to a + charge and soon get to +30 with the engine under load. The second set would do the same. Would I need to re polarize the regulator after putting in the new battery? It seemed like it started after the installation?Thank you. Link to comment Share on other sites More sharing options...
West Peterson Posted May 30, 2012 Share Posted May 30, 2012 My expert friend says it doesn't sound like your regulator or generator is the problem. Also, since it seems to start out okay, then move all the way over to the + side, it couldn't be a case of the points sticking. It's possible they could use some adjusting, but unless you know what your doing, you shouldn't try adjusting at this time.No polarizing needed, unless you've recently rebuilt the generator.First thing to do is look for some type of short on the hot line between the battery, starter and regulator. Something is telling your regulator that you have no battery. How old is your wiring? Is it the original cloth covered wire, or do you have a new harness with the cloth covered plastic covered wire? Look for some place where a cable or wire has rubbed against a ground.Is your battery cable 00-gauge? Many people make the mistake of installing a 12-volt cable, which is way too narrow of a gauge for six-volt operation.Let me know what you find out... good or bad. Feel free to pose more questions. Link to comment Share on other sites More sharing options...
Owen_Dyneto Posted May 30, 2012 Share Posted May 30, 2012 Although some other issue is possible, you've got the classic symptoms of a grounded field, either at the regulator, or within the generator, or in the field wire between the two. As someone has already pointed out, continuing to drive it this way may harm the generator but what will probably happen first unless you drive with the headlights on (as was done in the age before full generator control) is that you'll boil the electrolyte out of the battery, warp the plates, and be in the market for another new battery. Link to comment Share on other sites More sharing options...
Guest Commodore Posted May 31, 2012 Share Posted May 31, 2012 FYI the correct generator for your Packard 120 is an Autolite GCJ-4801-A. The generator you have assuming the complete part is 1102794 is from a 1953 - 1954 Pontiac. The regulator is correct. Link to comment Share on other sites More sharing options...
oldford Posted May 31, 2012 Share Posted May 31, 2012 The purpose of one of the coils in the regulator is to ground the fields as a method of regulating output. Sound like the regulator.... I'd replace it with a solid state unit if it were me...Frank Link to comment Share on other sites More sharing options...
West Peterson Posted May 31, 2012 Share Posted May 31, 2012 It's positive-ground car, so I think you'd ground the armature.... or do I have that backwards?In any event, the way to polarize the regulator is to touch the battery with the armature. But that is not needed unless you've rebuilt the generator. Link to comment Share on other sites More sharing options...
Guest bigtoyzII Posted May 31, 2012 Share Posted May 31, 2012 Thank you guys for all your advice. I have a lot of things to start checking and I wil get back to you to let you know what I find.I did wire the entire car from scratch using a correct wiring diagram. I purchased newer (plastic) covered wire with a wover look to it. I did not rebuild the generator. I have a woven ground strap but a modern battery cable. My dad has driven it occasionally for several years without saying anything about overcharging and I just got it back. I am sure there wasn't a high + issue before. Infact I did drive & run it some before just installing a new battery and it seems like that is when I realized it was overcharging. Going by the old numbers, I should have a new exact replacement regulator in a few days but if someone could recommend a solid state number I would rather go that route. I will check some of the other things suggested here and get back to you guys. If anyone thinks of anything else to try, I would appreciate it.Thank you. Link to comment Share on other sites More sharing options...
Guest Water Jacket Posted May 31, 2012 Share Posted May 31, 2012 BTZII -- Lotta savvy from the above gents. Should you need any further help on electrical or anything else on your One Twenty, and happen to live within comfortable driving range of Napa in the NorCal wine country, call Just Packards, 1 (707) 254-2046, as Steve and his associate specialize in late '30s, early '40s Packards, junior and senior. Tell him a black '47 Super Clipper in the East Bay referred you, and all best. Link to comment Share on other sites More sharing options...
West Peterson Posted June 1, 2012 Share Posted June 1, 2012 Modern battery cable???? Make sure it's not a 12-volt cable. 00-gauge is preferred. Link to comment Share on other sites More sharing options...
Guest bigtoyzII Posted June 6, 2012 Share Posted June 6, 2012 Just an update. I rebuilt the generator (it is a '53 pontiac) while waiting for the regulator. I changed out the - battery cable for a much heavier cable. The regulator that came in was VERY incorrect so I am still looking for a new one, preferably solid state. Any suggestions on this? I am going try to locate a '53 Pontiac regulator to try unless I get a lead on a solid state. The ammeter has settled down some, it now registers 0 to +15 idling and bounces a little higher at higher RPM. Flipping the lights on does bring it down to just to the + side of 0. And, now the regulator is buzzing off and on and the ammeter gauge fluxuates with the buzzing. I am hoping that I have narrowed it down but will keep you guys posted. I would really appreciated a suggestion on a solid state regulator.Thanks for all the help so far. Link to comment Share on other sites More sharing options...
1937-44 Posted June 6, 2012 Share Posted June 6, 2012 Hi, I can not recommend this company, only because I have never used them. I still run stock voltage regulators on my cars. However you might want to check out there website and talk to them: Wilton Auto Electric Good luck. Carl Link to comment Share on other sites More sharing options...
Guest Commodore Posted June 7, 2012 Share Posted June 7, 2012 The part numbers for a non-solid-state regulator are:Standard VR8, Airtex/Wells 1V1062 and NAPA VR1071. Link to comment Share on other sites More sharing options...
Guest bigtoyzII Posted June 9, 2012 Share Posted June 9, 2012 Great news. I have the ammeter reading correctly again, just above +0, lights on or off. After installing a correct battery cable, rebuilding the generator, ect, I found the regulator points buzzing when I physically rocked the regulator body slightly(?). I filed the points but I think the real problem was the corrosion/poor contact at the 4 wire connections points on the outside of the regulator. I think it was struggling to turn off & on. I did find a 4 lug 6volt + ground point type regulator that maxs at 10 amp/7.5 volt. I will keep it as a backup and I will post the part numbers tomorrow.I want to thank everyone for all the suggestions and help. Its great knowing where to go to find such great help. Link to comment Share on other sites More sharing options...
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