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| | | | Joined: Mar 2007 Posts: 460 Shop Shark | | Shop Shark Joined: Mar 2007 Posts: 460 | Slowly but surely we've been installing my wiring harness in the '37, but today got to connecting the gauges and hit a wall since we didn't want to take a chance on frying them... My '37 was upgraded to 12V when it was hot rodded by the previous owners, but they also added some newfangled 12V gauges at the time that I have discarded in favor of the "original equipment" gauges that came with the truck when it was stock... What is required to make 6V gauges work properly (without a smoke show in the cab) using a 12V system? Looking forward to hearing about your experiences in this area and specifically what you had to do to make yours work... Thanks in advance...  ~Trev | | | | | Joined: Sep 2001 Posts: 29,270 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,270 | | | | | | Joined: Dec 2007 Posts: 1,403 'Bolter | | 'Bolter Joined: Dec 2007 Posts: 1,403 | Requires a voltage reducer in the gas gauge power feed and any other 6v accessory, and I think that is it, besides changing out any 6v bulbs. | | | | | Joined: Mar 2007 Posts: 460 Shop Shark | | Shop Shark Joined: Mar 2007 Posts: 460 | The bulbs were already swapped out when they did the conversion, jdl... in a way I am simply reversing part of their 12V conversion in going back to the original 6V gauges... I do have a 12V to 6V converter box under the dash already but it is not in use for the gauges... can I patch into that and will it work or do I need seperate reducers for every gauge? Thanks for the link to the tech tip, tclederman... My buddy who is working with me on the project and I actually looked at a few of them today and obviously didn't find the right tip to come up with a conclusive answer... I'll take a look... ~Trev | | | | | Joined: Aug 2005 Posts: 6,377 Ex Hall Monitor | | Ex Hall Monitor Joined: Aug 2005 Posts: 6,377 | Trev, back in the day I had a 55.1 panel truck that I converted to 12v. I did nothing with the gauges (didn't occur to me then that I might need to) and had no problems at all. I noticed that the gas gauge stayed on full longer but nothing fried and all the other gauges worked the same pre & post. I'm not sure about your converter box because I've never used one. It seems reasonable that it would work with the gas gauge. Having followed similar threads here before it seems the gas gauge is the largest concern.
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| | | | | Joined: Jan 2002 Posts: 2,254 'Bolter | | 'Bolter Joined: Jan 2002 Posts: 2,254 | What is the ballast resistor that is mentioned in the Tech Note between the ignition switch and coil? Where can they be found?
TIA
Dennis
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| | | | | Joined: May 2004 Posts: 1,312 'Bolter | | 'Bolter Joined: May 2004 Posts: 1,312 | Trev........what will you do with Oil Pressure Gauge ?. As I recall original only goes to 30 psi ?. As well, it is a tube actually filled with oil vs. electric sending unit. | | | | | Joined: Mar 2007 Posts: 460 Shop Shark | | Shop Shark Joined: Mar 2007 Posts: 460 | Trev........what will you do with Oil Pressure Gauge ?. As I recall original only goes to 30 psi ?. As well, it is a tube actually filled with oil vs. electric sending unit. Correct! Actually yesterday we removed the "new style" fitting that was on the oil pressure line to an old fitting that was on the gauge and that went on fine... we started the truck and pinned the gauge at the full 30 p.s.i. so not really sure if there's much point in having it running if it just stays pinned... My concerns were more with the other gauges (since that one apparently works with the adapted line)... the gas gauge and electrical stuff so I thought it would be better to ask now than fry a nice set of old gauges...  ~Trev | | | | | Joined: Dec 2007 Posts: 1,403 'Bolter | | 'Bolter Joined: Dec 2007 Posts: 1,403 | The only thing that you have to worry about frying would be the gas gauge, unless you are putting in any other 6v accessory. As far as a reducer or anything, the gas gauge will work on the reducer that you have already, but I'm not sure it will be accurate. If you want to be sure that the gauge will read accurately, then take a look at this link. It has the reducer you need at the bottom. | | |
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