Before condemming the alternater or voltage regulater (it's inside the alternater) MAKE SURE that all of your grounds are clean and tight. Pay particular attention to the ground cable from the battery and the ground point on the frame inside the front left wheel to the frame. A bad connection can cause all kinds of weird problems and if you start replacing parts before fixing the ground connection you will be wasting a lot of money and time and getting frustrated. It only takes a few minuets and doesn't cost anything (assuming the cables are there!) Hot weather doesn't affect the voltage regulater, they have temperature compensating circutry in them, but it does affect the output of the alternater. As electrical components (wiring and alternater) get hot they carry less current. Also the belt will tend to slip if loose in the heat (it streches a little). At the same time the electrical system is under the most stress, ie: heat and high demand from the engine, cooling system and A/C, the cooling system is also under high demands and of course if it's dark you also have the headlights going. This is the scenario that the Ducy couldn't keep up with. It's hard to imagine but under high demands a car can use more electric than a small house! Upwards of 100 amps! Also consider when starting the motor the momentary draw is over 300 amps! This is why all connections MUST be clean and tight. Some of the branch circuits (like the cooling fans) draw 30 amps continuosly. The wiring is only rated for 30 amps but not continuosly! This is why you need to allow the fans to cycle either on the otterstadt or the low pressure A/C switch. It gives the circuit a chance to cool and not heat up to max. It also points out why it is important to check all of the connections in the fuse/relay panel. When you go out for a drive in the heat put your hand behind the passenger seat and feel the heat from the fuse panel. Some owners leave the carpet and cover off to help keep it cool. It becomes a vicious cycle because the hotter it gets the higher the resistance, the higher the resistance the hotter it gets. Some cars have actually caught fire from this. I personally have seen a fan fail bypass burn and almost set the car on fire. Because it is a hidden area may people never even look at the fuses. David Teitelbaum vin 10757 --- In dmcnews@xxxx, dherv10@xxxx wrote: > Andy, Sounds like the regulator in the alternator is going out or has gone > out. This hot weather all over the country is playing havoc on them. Delco > has changed their specifications two or three times in the last couple of > years and even though they try to do better, sometimes it's not quite as good > in all applications. They try to make one device fit as many applications as > possible. We are always looking for the better regulator. I'm am going to > start adding a diode in the light wire to try to stop some potential feed > back problems. > John Hervey > http://www.specialtauto.com/