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| | | | Joined: Aug 2005 Posts: 1,186 Shop Shark | | Shop Shark Joined: Aug 2005 Posts: 1,186 | Fired Barry up a couple days ago and of course the 12 volt battery from 2005 is just a little weak. I want to convert Barry back to 6 volt. My questions are as follows..
1. I can't find the little ceramic block that cuts the voltage down anywhere on the truck. Is there one??
2. Obviously I need a new battery, can I go buy a 6 volt and just slap it in and go or do I have to go 12 volt until I convert it back? I will replace the alternator with a 6 volt generator. The starter still looks 6 volt.
3. The coil on the truck now is 12 volt. Should it be 12 volt or six volt right now? It gets REALLY hot after I run the truck for a bit.
4. What type of coil do I need for either 6 or 12 volt...external or internally regulated?
I need to get this big boy back on the road soon so any help would be great.
Bruce | | | | | Joined: Mar 2012 Posts: 240 'Bolter | | 'Bolter Joined: Mar 2012 Posts: 240 | I'm no expert, but I've converted my truck to 12V successfully. Ultimately, you need to go back through the conversion steps "in reverse": http://www.stovebolt.com/techtips/12_volt_conversion.html From my reading, understanding, and experience: 1) If your coil has an "internal resistor", you won't find (and don't need) the voltage reducer you're looking for. 2) Nope. You need a 12V battery in a 12V system. (you'll either not get the charging system to work on that low a voltage, or you'll cook the battery if it does); Most folks (including me) run the 6V starter on a 12V system. My understanding is there are different starter pinion gear sizes between a 6V and a 12V that would require a flywheel change to make a correct mesh. 3) You'll need a 6V coil if you convert it to 6V. As it is, you need a 12V coil (not sure what to make of the apparent coil temp, maybe it doesn't have an internal resistor and needs one). 4) 6V coils aren't offered with internal resistors - they don't need them (assuming you're running in a 6V system). I'm sure that others will have additional thoughts or comments. Good luck and best regards, Bill
1947 3100 Advanced Design
Never, never, never, never give up. - Churchill
| | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | 6V systems had no ignition resistor [ceramic block] - with the coil getting hot sounds like whoever made it 12V didn't add one, cross it off your list, and switching back to 6V, get everything new 6V, including the coil now that one has been abused
Bill | | | | | Joined: Aug 2005 Posts: 1,186 Shop Shark | | Shop Shark Joined: Aug 2005 Posts: 1,186 | So if I understand correctly which my wife says I never do, I pull the alternator and reinstall a generator. Pull the 12 volt coil and put in a new 6 volt coil. Then pop in a 6 volt battery and I should be good? It sounds too easy.
Bruce | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | that's the nice part about an old truck - simple  what else is there? might check if all the light bulbs were changed to 12V, in which case you'll need to change'em back - also make sure you have good heavy gauge ['0' or even '00'] battery cables, and see if there's been any dropping resistor added to the gas gauge Bill | | | | | Joined: Aug 2010 Posts: 775 'Bolter | | 'Bolter Joined: Aug 2010 Posts: 775 | Has the wiring been changed? 6V draws more current. If the wiring is original it should be fine. If it was changed when it went to 12V you need to make sure it is the right gage for 6V. 6V was a larger heavier gauge. | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | So if I understand correctly which my wife says I never do, I pull the alternator and reinstall a generator. Pull the 12 volt coil and put in a new 6 volt coil. Then pop in a 6 volt battery and I should be good? It sounds too easy.
Bruce Reinstall the 6v generator AND the 6v voltage regulator. If you have a 12v starter, you'll need a 6v starter. | | | | | Joined: Aug 2005 Posts: 1,186 Shop Shark | | Shop Shark Joined: Aug 2005 Posts: 1,186 | I'm pretty impressed with myself! Even though I don't know squat about electrical, I converted Barry back to 6 volt today. I changed out the alternator for the generator I went through, used the matching voltage regulator which was originally with this generator. Polarized the generator and slid in a new 6 volt coil and battery and it wouldn't start! Swapped out the starter which was a rebuilt 6 volt for an old 6 volt starter I had in the parts bin and woosh.....fired right up. I guess shooting 12 volts through the 6 volt starter destroyed the fields. Anyway it works great! Now back to the still malfunctioning brakes, master cylinder kit is due in Monday. 
Bruce | | | | | Joined: May 2005 Posts: 8,983 Sir Searchalot | | Sir Searchalot Joined: May 2005 Posts: 8,983 | I'm impressed with the guys that helped you and what I learned from this. Thanks guys!
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
| | | | | Joined: Oct 2010 Posts: 1,232 'Bolter | | 'Bolter Joined: Oct 2010 Posts: 1,232 | Congrats on bringing Barry back to his 6-volt roots. I wish that I had done the same when the 12v generator and regulator went out on my '54 that a PO had converted to 12v. It would have been a cheap fix, since I had to replace the generator anyway.
- Lonnie
- Lonnie My '54 3104Photos that I have shared on Stovebolt via PhotoBucket are no longer available. Please contact me if you want a photo from an old post. lonniecook [at] aol [dot] com. I sold my '54 3104 12/12/2017, but I still visit Stovebolt. OLD STUFF ... houses, furniture, cars, wine ... I love it all | | |
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