jgkurz 52 Report post Posted January 13, 2015 Hi All,My 69 Mach1 came with a Temperature gauge on the far left of the gauge cluster. I would like to change at this gauge to the Alternator gauge that came on different 69 models. The two gauges seem to have the same mounting and should easily swap. I think the Alternator gauge is actually an amp meter. I plan to run a mechanical water temp and oil pressure gauge in the console and don't want the redundant water temp gauge. I like the classic look of the original gauges in the cluster which is why I'm going through the trouble.I don't know if the original dash wiring/ribbon cable will support the gauge swap. If not, fabricating the amp meter and dash light wiring shouldn't be too hard.Is there reason why my plan won't work?Thank you,John Quote Share this post Link to post Share on other sites
buening 63 Report post Posted January 13, 2015 The temp gauge came with the tachometer cars. You have a fuel gauge at the far right correct? The printed circuit (gauge ribbon) is completely different between tach and non-tach cars (as is the underdash harness). You would have to cut the printed circuit ribbon that touches the posts for the temperature gauge, and then run wires from the alternator to the gauge posts. Indeed it is an amp meter and is pretty useless as a gauge, FYI. Quote Share this post Link to post Share on other sites
jgkurz 52 Report post Posted January 13, 2015 Correct, I have a fuel gauge on the right side. I agree the Alternator gauge is almost useless but it will tell me if the alternator is charging (with a slight swing to the right) but that's about it. I wasn't sure if the ribbon was similar between cars. Sounds like I will need to fabricate the wiring. Rather than run a new wire directly to the alternator I was hoping there was a factory wire from the alternator somewhere in the dash. From your post, I now know the ribbon and harness are different. This leads me to believe the non-tach cars had a special wire directly to the alternator. I will research that before I start running my own wires. Thank you. Quote Share this post Link to post Share on other sites
1969_Mach1 333 Report post Posted January 13, 2015 I have rewired a 69 Mach to switch from a non tach IP to a factory tach IP. There are many differences. I would not attempt what you are trying to do. Have you thought of leaving the gauge setup as is and installing a mechanical oil pressure gauge and a voltmeter in the console? I would definitely leave the existing oil and amp warning lights intact and functioning because from my experience the gauges on the console are so far out of your line-of-sight you don't look at them. The console is a not the best location for gauges. Quote Share this post Link to post Share on other sites
jgkurz 52 Report post Posted January 13, 2015 I definitely want to keep the oil and amp warning lights. I agree that the lights provide an immediate warning that the gauges will not. My plan was to swap in (and wire) the factory Alternator gauge but still use the warning lights. I did think about continuing to use the factory temperature gauge but I wasn't sure if I could trust it plus it's vague. My setup is not that street friendly so keeping a close eye on coolant temps will be important. What is your experience with the factory temperature gauge? Quote Share this post Link to post Share on other sites
Wycked69 20 Report post Posted January 13, 2015 (edited) If our car did not have a factory tachometer, then the gauges were (from left to right): Ammeter, Speedometer, Fuel/Temp gauge combo, and oil pressure. If your car had a factory tachometer, then the gauges were (from left to right): Temp, Speedometer with Trip Odometer, Tachometer, and Fuel. The ammeter and oil pressure gauge was deleted and an oil pressure warning light and charge indicator light were at the lower tachometer face. So if you indicate you had a temp gauge, then your car was a factory tach car and even though the ammeter gauge will properly mount at the far left, you will have to figure a way to wire (connect) the ammeter gauge while not using the existing cluster circuit. Since your car would originally have what is sometimes referred to as an "idiot light" for the charge circuit, the instrument circuit is different not to mention the under dash harness and headlight to firewall harness is different. I see no reason why you could not wire the ammeter circuit as a stand alone circuit. (Looks like I said mostly the same thing as everyone else) Edited January 13, 2015 by Wycked69 Quote Share this post Link to post Share on other sites
Wycked69 20 Report post Posted January 13, 2015 I definitely want to keep the oil and amp warning lights. I agree that the lights provide an immediate warning that the gauges will not. My plan was to swap in (and wire) the factory Alternator gauge but still use the warning lights. I did think about continuing to use the factory temperature gauge but I wasn't sure if I could trust it plus it's vague. My setup is not that street friendly so keeping a close eye on coolant temps will be important. What is your experience with the factory temperature gauge? I have not done this on my 69 (as I have not started the restoration) but on my 68 FB, it has a factory tach set up which in turn has the idiot lights for the charging circuit and oil pressure. I wanted to also add gauges for my charging circuit and oil pressure as I did not want to rely on the idiot lights. Since I did not want to cut up the console or dash, I simply made a holder to hold an electrical oil pressure gauge and ammeter gauge to replace the ash tray (I kept the ashtray). I wired the gauges in without splicing wires. The oil pressure was an electronic type so the sending unit was simply fitted to the oil galley on the top of the block behind the manifold. If I can figure how to upload a couple pic's, I will Quote Share this post Link to post Share on other sites
Wycked69 20 Report post Posted January 13, 2015 And I kind of figured out how to attached pic's Well, let me see if I can rotate and re-upload (I'm not so computer or IPhone savy) Quote Share this post Link to post Share on other sites
Wycked69 20 Report post Posted January 13, 2015 Lets try this Well,.......... You get the point Quote Share this post Link to post Share on other sites
1969_Mach1 333 Report post Posted January 13, 2015 I definitely want to keep the oil and amp warning lights. I agree that the lights provide an immediate warning that the gauges will not. My plan was to swap in (and wire) the factory Alternator gauge but still use the warning lights. I did think about continuing to use the factory temperature gauge but I wasn't sure if I could trust it plus it's vague. My setup is not that street friendly so keeping a close eye on coolant temps will be important. What is your experience with the factory temperature gauge? You're right, the original temperature gauges are not very accurate. In your case it would be simpler to have the original ammeter converted to a volt meter. The additional wiring to connect a voltmeter is much simpler than an original ammeter. The appearance is not altered just the functionality. Here is one place that can do the gauge conversion, http://rccinnovations.com/index.php?show=menu-volt-all . A volt meter is a better indicator of the charging and battery condition. If I had an extra ammeter I would do the conversion because the original ammeters do not work very well. Then install a temp and oil psi gauge of your choice in the console as you originally planned. I think this would be the easiest way to accomplish your goals. Quote Share this post Link to post Share on other sites
jgkurz 52 Report post Posted January 13, 2015 You're right, the original temperature gauges are not very accurate. In your case it would be simpler to have the original ammeter converted to a volt meter. The additional wiring to connect a voltmeter is much simpler than an original ammeter. The appearance is not altered just the functionality. Here is one place that can do the gauge conversion, http://rccinnovations.com/index.php?show=menu-volt-all . A volt meter is a better indicator of the charging and battery condition. If I had an extra ammeter I would do the conversion because the original ammeters do not work very well. Then install a temp and oil psi gauge of your choice in the console as you originally planned. I think this would be the easiest way to accomplish your goals. WOW! What a great idea. I am going to do this conversion. Thank you for the link. Quote Share this post Link to post Share on other sites
jgkurz 52 Report post Posted January 13, 2015 Lets try this IMG_0178.JPGIMG_0179.JPG Well,.......... You get the point Thanks for the info and pics. I do get the point. : ) Quote Share this post Link to post Share on other sites
1969_Mach1 333 Report post Posted January 13, 2015 I think the ammeter to volt meter conversion is a good idea. Eventually I want to do mine. Good Luck. Quote Share this post Link to post Share on other sites
Guillaume69 150 Report post Posted January 13, 2015 I have just done this (using RC Innovations for amp to volt internal conversion) and it is really nice. A little adaptation is required on the printed circuit, but after this, you have a functional gauge that reads what tension your VR is delivering to the battery. Pretty cool, IMO. Quote Share this post Link to post Share on other sites
danno 128 Report post Posted January 14, 2015 You can still do the alternator gauge replacement if you would want to. It would require its own wires, like shown above. You cannot use the flextape, it would be a lot of cutting and splicing. Then you would need to add a resistor that the wires above would connect to. It could be done. I have added the extra resistor to get my ampmeter working. The factory ampmeters never worked good at all, they were not designed correctly. But by adding a resistor, you can get it to work. I can explain more if you want, but converting to a voltmeter is also a good idea. Quote Share this post Link to post Share on other sites
SA69mach 39 Report post Posted January 15, 2015 You can still do the alternator gauge replacement if you would want to. It would require its own wires, like shown above. You cannot use the flextape, it would be a lot of cutting and splicing. Then you would need to add a resistor that the wires above would connect to. It could be done. I have added the extra resistor to get my ampmeter working. The factory ampmeters never worked good at all, they were not designed correctly. But by adding a resistor, you can get it to work. I can explain more if you want, but converting to a voltmeter is also a good idea. Please do explain. I have had my gauge clusters out in the 70 and the 69 Mach 1, and both are all working, but both ampmeters seem to be 'inactive'. I only ever see the slightest movement, and would love to know what resistors to install, and where. Would like to have the factory gauges working correctly. I have a working knowledge of the 69 and 70 gauges, wiring, senders and voltage system. If I cant get the amp meters working I will be changing them out for volt meter conversions. Any info appreciated Quote Share this post Link to post Share on other sites
danno 128 Report post Posted January 15, 2015 The ampmeter has 2 wires on it that go from the instrument cluster, through the firewall, and to the wire harness. The two wires connect to different locations of the same wire. Look at a schematic, they connect to the same place. The different locations on the same wire has a certain, very small resistance in it. The ampmeter is sensing the voltage drop in the resistance of this section of wire. The trouble is the resistance is not large enough to move the ampmeter. The solution is to do one of the following. 1 increase the resistance in that section of wire 2 increase the windings in the ampmeter so it actually moves 3 install an amplifier so the small resistance in the wire is amplified and will show up on the ampmeter. Each of these solutions has an advantage and disadvantage. The resistor has a problem because it need to be large. For solution 3, I have designed an amplifier that just bolts onto the back of the ampmeter. No wires to cut or any complicated installation. I will see if I can finish it soon. I will get back to you with more information on the resistor idea. Quote Share this post Link to post Share on other sites
SA69mach 39 Report post Posted January 16, 2015 Great ideas. Looking forward to the results with the amplifier. Seems like some possible solutions to the lifeless nature of the factory amp meters. Quote Share this post Link to post Share on other sites
stangs-R-me 120 Report post Posted January 16, 2015 I did this on my '69 back in the 80's. My car originally had a non-tach dash and I picked up a tach dash & dash wiring harness for it. I also did not want idiot lights for oil PSI & ALT, but did not want to do a real ALT gauge like '69 Shelby. Looking at the wiring diagrams I noticed the headlight harnesses are different and of course were not being reproduced back then. I then noticed that '69 Cougar XR7 which has "full instrumentation", used the non-tach Mustang headlamp & alternator harness's. So if I figured out how to swap the ALT gauge from the non-tach dash to the tach dash, I would not need to find a good used headlamp & alternator harness from a tach car. I also like to keep things as factory looking as possible, and don't like doing modifications that can't be easily reversed. First I took the alternator wires out of my original non-tach dash harness and pulled the Oil PSI & Water Temp wires out of the instrument cluster plug. The original tach printed circuit line that goes to the sender was re-used, the other side of the alt gauge I ran a separate wire as the printed circuit goes to the VR. I then ran wires up to the cluster plug area and taped the wires to the original connector terminals (did not cut / splice) for the Oil & Water gauges that I added in a Shelby-type pod in the console ash tray spot. Since the ALT gauge is not all that functional, I also added a Voltmeter in a Autometer pod that mounts to the lower cluster screw below the speedo. I also took a copy of the Ford Wiring Diagram and made a diagram showing MY added gauges. Trying to upload pictures and the wiring diagram (1st attempt at this new site) and it is not letting me do any attachments. However, just checked and the "pictures gallery" is still on the old site so here is a link to my pics there ... http://www.1969stang.com/gallery/stangs-R-me-Deluxe-GT-Hardtop?page=2 If anyone wants a copy of my wiring diagram, send me a PM with your e-mail and I'll send you a PDF copy of it. Doug Quote Share this post Link to post Share on other sites
stangs-R-me 120 Report post Posted January 16, 2015 Alternator Gauge sensitivity ... When I 1st got my car in the early 80's, it had a std. black non-tach dash and this alternator gauge actually worked ... as in ... it would swing towards negative when you turned on headlights etc. with engine not running and would show positive swing when the alternator was charging. I think I even swapped in a nicer std. black cluster at one point and that gauge worked properly too. However the alternator gauge in the deluxe woodgrain dash I eventually swapped in (and is now in my tach cluster) never showed much movement. I have since replaced my headlamp & alternator harness's with new Alloy Metal repros and I still have no ALT gauge movement. Someone had mentioned a while back (guessing Danno or Midlife) to clean up all the connection points in the alternator gauge circuit. I figured the new headlamp harness is half of the circuit, I've yet to try and clean up the connections in the dash harness. Doug Quote Share this post Link to post Share on other sites
Midlife 814 Report post Posted January 17, 2015 I rarely see bad continuity or connectors for the ammeter lines. I think it was just a crappy design Ford used. To make the ammeter work better, you actually need to add resistance to one of the lines, so the more corroded a connector is, the better performance ot the ammeter! Go figure... Quote Share this post Link to post Share on other sites
SA69mach 39 Report post Posted January 17, 2015 Thanks for the info Midlife. I would like to add in a resistor and see if the meter could be a bit more lively and useful. On the stock instrument (non tach) cluster, the printed circuit makes the connection for the two terminals of the gauge. Would a 10 amp resistor across both terminals - with no other changes- do the job? Or another resistance value, if you know? Quote Share this post Link to post Share on other sites
Midlife 814 Report post Posted January 18, 2015 No, you need to add a resistor in line with one of the ammeter lines, not across the two terminals. I'd start with a 10 ohm resistor, perhaps using the wiring for a in-line glass fuse holder. Insert it on either the yellow or red line on the harness itself. Quote Share this post Link to post Share on other sites
SA69mach 39 Report post Posted January 18, 2015 Gotcha... When I have the instruments apart I will try it. Any particular type of resistor more suited to this? I only know of two, the ceramic type and the diode type. would a 10 amp glass fuse be of any use, or is there not enough resistance built in to that? Quote Share this post Link to post Share on other sites
Midlife 814 Report post Posted January 18, 2015 No resistance in a glass fuse. I'd use the ceramic type of resistor, but keep it away from other wires as it will get hot. Quote Share this post Link to post Share on other sites
