I unbolted the silver box / presumed regulator from the bakelite board it was attached to. The 67 terminal has a white wire going to it and the 15 has a red one. The wiring diagram says I should see green, white, and black wires, but I have red, white, and (the ground bolted to the housing) black. The red wire goes to the fuse in the fuse box marked Regulator The Measuring voltage between the terminals where they enter the device on the back side and the ground wire I get:' When the ignition is on but the car is not running I get 10.2v to the 67 terminal and 11.2 to the 15 with the car running at 2000 rpm and the headlights NOT on, I get 13.5 and 14.2 with the car running at that speed and the lights ON, I get 11 and 12. The voltages with the car running seem to fluctuate constantly, but those are averages. The ammeter shows 0 with the ignition off, some negative with the engine running at 2K, and more negative when the lights are turned on. Image Unavailable, Please Login
Jim - I studied the link Scott provided, and found a few of my own comments (2008). I have copied one below: "Scott - sorry to hear of your twitchy amp meter. However, old-style electromechanical voltage regulators will, by their nature, result in discontinuities (on-off) and "twitchy" amp meters. After all, unlike a modern transistor regulator, the electromechanical regulator is an on-off device. Either it charges the battery (plus amp meter movement) or the battery discharges (negative amp meter movement). There is no gradual "seeking" of a zero current condition. It is referred to as a "Bang-bang" feedback control system. My comments may be without merit if your amp meter, heretofore, was as smooth as silk. I would be surprised if that was the case. It is more likely that if you had a smooth amp meter, then something was wrong to lead to a smooth amp meter, rather than the opposite. I invite others to discuss this issue. It is interesting, as old-style electromechanical regulators are not seen often. They are most commonly seen today in old Jaguars, the true Vanna Whites of the automotive world...they look great but do nothing. After all, a moving violation in a Jaguar is an oxymoron. Jim S. " Your older type of mechanical "bang-bang" regulator will lead to twitchy amp-meter movement. But if it previously was smooth, and is now jerky, then I would not attribute the symptom to the regulator. Terminal 67 is the Field output of the regulator on later model schematics. Your voltage measurements are not consistent with a properly functioning regulator, HOWEVER, I do not have the schematic for the earlier model. Pin 67 on my Dino would find voltage going UP when the lights are turned on. Please check continuity of pin 15 with + positive battery terminal. With the relay open (car turned on but not running), pin 15 should read the same voltage as the battery. A continuity tester will confirm (zero Ohms) that 15 is, indeed, the positive bus supply. Pin 67 (with relay open, that is, not running) should not have continuity with positive battery OR ground. Come by and visit anytime and we can test further. Jim S.
Steve, What's the status of your problem? If it's still the same, may I suggest a simple check which I don't think anyone has mentioned and MAY be related. I had a problem with the connection of the alternator's heavy gauge wire to the black fuse box on the firewall (upper right corner as you view the engine from the rear of the car). The wire comes into the box from below - - directly from the alternator. That connection became loose because the wire from the alternator was not supported near the attach point with the fuse box. The wire was moving with the car movements and vibrations. Consequently, the attachment would become loose, the resistance would increase, the connection would overheat, the bottom of the fuse box would melt, the resistance would increase even more, etc, etc. You may want to check that connection for tightness and evidence of overheating. The photo below shows the box with the cover off as I'm disconnecting it from the firewall. You can see the red wire coming from below, turning black and melting the box at the connection point. Bill Image Unavailable, Please Login
Thanks, Bill, I had the cover off that box today to check / clean / apply dielectric grease to those two fuses and didn't see anything amiss. However, I didn't specifically check that connection and will do so. Jim
Does this look like an old "bang-bang" regulator? I saw the one in John's thread and this does not look deep enough to house the coil of wire shown in that photo. Also, while I don't make a habit of studying the ammeter as I drive, I do not recall ever seeing jump from pos to neg and back as you describe a bang-bang type would do--it would jump from one positive reading to a higher one for a split second, then return, but that's all. The 11.2v when the car is not running is confusing to me, also. I do have an FIA-approved battery cutoff switch, but I used very large gauge leads to it, and the car is on a battery maintainer most of the time. However, I wonder if that black ground wire is very good-- when I tried to measure the resistance between it and the windshield wiper stud / flanged shaft the gauge still read infinity. Would a bad ground wire lead to the VR misbehaving? Jim
update-- the wire at the 60 amp fuse is not loose The black ground is good when tested to a screw holding one of the trunk cover rubber bumper pads at the 60 amp fuse I get 13v with the car not running, while the battery line at the VR shows 11.2v. So there must be some voltage drop over the wires leading to it. I think my VR is bad. Superformance sells only 2 VRs for the Dino- an aftermarket electronic one for GBP 20 or what looks like an old points type for GBP 70. http://www.superformance.co.uk/a-246/electrical.htm anyone have any experience with the electronic one?
You might consider purchasing the inexpensive, modern regulator, while leaving the original, non-functional regulator on the board. Simply disconnect the wires and attach to the new regulator, and then hide it somewhere behind the air duct. Jim S.
My interpretation of the sticker on the back side of the unit in the car now (see photo of it off the bakelite mounting board) is that it was made in Oct 1984, so isn't it a modern one?
The electronic one offered by Superformance looks quite like the Hueco i recommended before. Works great and is inexpensive. The one you have currently installed is not original but an after market item so no harm in replacing it. Image Unavailable, Please Login
Fiat Plus sells one that can be used on many Fiats and the Fiat Dino. Would this one be fine? http://www.fiatplus.com/1968-77-a-market-voltage-reg-pr-278713.html TRutlands answered my email that they have a solid state one for $300. I wrote back asking what is so special about it. We'll see what they say Jim
Jim, that seems to be the same one, looks good! 'Solid State' just means that the regulator is electronic and uses no mechanical parts (compared to the original Dino regulator which is an electromechanic device). The Hueco regulator is also a solid state device. $300 seems to be a bit expensive though. Adrian
