doogan Posted August 9, 2016 Report Share Posted August 9, 2016 Once again I'm at a loss as to what the problem is. This is a 1949 B1 that has just finished a total off frame restoration. Here is the story. This problem existed when I got the truck last year and started the restoration and now it continues so I've missed something. Problem: the amp gauge pointer sits in the center "0" location all the time until the lights are turned on. Then it shows a discharge and will not move toward charge no matter how fast the engine turns. I have tested the generator and it is putting out 7.1 volts. I used the jumper on the regulator grounding the field terminal to the engine block and the amp gauge goes fully to the charge side. Replaced the regulator with one from a working truck and it does the same thing. I have followed every wire and they are just at the wiring diagram shows they should be. All lights, horn, stop lights, wiper and heater blower work. At idle the regulator will have a hard click about every 2 seconds and the amp gauge needle will wiggle at each click but nothing else. The only thing different than the wiring diagram is there is an 8 volt positive ground battery used rather than the 6v. Anyone ever had this problem or is it just me? Any suggestions would be appreciated. Thanks Don Quote Link to comment Share on other sites More sharing options...
JBNeal Posted August 9, 2016 Report Share Posted August 9, 2016 I have a similar problem on my '49, I am assuming that the amp gauge got fried but have not verified this. The 6V battery has plenty of oomph to crank the starter, I do not drive it at night so I have not put this issue high on the priority list...I recall finding several amp gauges on eBay over the years, so I'm guessing that amp gauges would fry frequently...the amp gauge is a shunt, so system voltage should not be interrupted if the monitoring circuit malfunctions Quote Link to comment Share on other sites More sharing options...
_shel_ny Posted August 9, 2016 Report Share Posted August 9, 2016 Does your voltage regulator have a good ground connection. May be necessary to scrape a bit of paint to get a good ground. Quote Link to comment Share on other sites More sharing options...
Merle Coggins Posted August 9, 2016 Report Share Posted August 9, 2016 7.1 volts is not enough to charge an 8 volt battery. You may only be reading battery voltage. I suspect that your generator or regulator are indeed faulty. 1 Quote Link to comment Share on other sites More sharing options...
doogan Posted August 9, 2016 Author Report Share Posted August 9, 2016 Well it is finally fixed. After doing all the test on the generator and regulator as shown in the manual, rechecking the wiring diagram and tracing all the wires, testing the gauge and finding nothing out of order I decided to move to the only area I haven't touched. The battery. So I removed the 8 volt battery and replaced it with a 6 volt out of my A model. First I cranked the truck with the 8 volt still installed. While running I removed the 8 volt battery. This proved the generator was putting out voltage as the engine didn't die when the battery was disconnected. The 6 volt battery was installed battery cables hooked up and when the engine was sped up walla!!! it was charging and showing a strong charge on the amp gauge. I don't know why, how or what the problem was but it is now working and that is all I needed. So tomorrow its to town and get a 6 volt with at least 625 CCA and put the 8 volt aside. The pilot house is back on the road and running fine. Enjoy the ride and keep 'em going. Thanks Don Quote Link to comment Share on other sites More sharing options...
Jerry Roberts Posted August 9, 2016 Report Share Posted August 9, 2016 Optima makes a 6 volt battery that packs a wallop . Drawbacks are the odd shape and the high price . 1 Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted August 9, 2016 Report Share Posted August 9, 2016 (edited) bulletin...Optima can be stuffed into a conventional looking shell that would not draw attention to itself....for sure they pack a whallop...best reserve battery I have found this item comes under the "Pay to Play" heading...when looks are extremely important... http://www.ebay.com/itm/Original-Style-Battery-Case-Hides-6-volt-Optima-Battery-Classic-Vintage-Cars-/232027798356?hash=item3605ef3b54:g:tRwAAOSwqu9UzxkP&item=232027798356&vxp=mtr Edited August 10, 2016 by Plymouthy Adams Quote Link to comment Share on other sites More sharing options...
Merle Coggins Posted August 10, 2016 Report Share Posted August 10, 2016 On these trucks the battery is hidden under the floor so it doesn't really matter what it looks like. I believe the issue was that your regulator was never readjusted for the 8 volt battery, so even though your generator was putting out 7 volts it wouldn't charge the battery, so you'd never have current flow back into the battery enough to show up on the ammeter. Merle 6 Quote Link to comment Share on other sites More sharing options...
Jim Roach Posted August 10, 2016 Report Share Posted August 10, 2016 Here is a picture of the Optima battery in my 1955 Thunderbird. I cut the top off and hollowed out the old battery. I inserted the new Optima battery on an angle so the posts were in opposite corners. Then I built a new top and you can see the results. These batteries spin my 292 like it was a 12V system. 2 Quote Link to comment Share on other sites More sharing options...
Jocko_51_B3B Posted February 29, 2020 Report Share Posted February 29, 2020 Doogan, I think Merle has the right answer. Current can't flow from a 7V source to an 8V source. Good that you figured it out by trial and error. 1 Quote Link to comment Share on other sites More sharing options...
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