No battery charge when temp hits operating temperature. I measured ~70C on the shell of alternator with my Infrared thermometer when charge disappear. That may explain why the two electric shop where not able to find any problems with my alternator.
Update Aug 3: Bought a used 2003 alternator from ebay seller youngstn. It was priced at US$ 74.95 (including free US shipping). It was installed Aug 1 and found to be working perfect. I have had a volt meter in the car for the last few days and found that voltage never drops lower than 13.8 volt measured in the auxillary output plug inside console, even thou temprature have been way above 30 the last few days with rear defroster and AC on.
Even the new alternator measured 70C in the summer, so this is normal. What is happening here is that alternator does not reach 70C in testbench in a electrical shop, so they simply could not reproduce it. To me, this sounds like I had a partially malfunctioning regulator in alternator.
Problems while removing these parts:
- Belt tensioner screw rusted stuck to bracket. I guess the 5 years of Ontario salt killed it. Belt tensioner is supposed to work like this: Loosen idler pulley. Turn tensioner anti-clockwise until idler pulley can be moved up/down about 25mm. This is supposed be enough to get belt off. I had to cut belt off (which was ready for replacement anyways at ~100 000km), and purchase a new bracket ($24) and idler pulley assembly ($121) from Nissan Scarborugh.
Problems while installing:
- Lower tensioner bolt on alternator was impossible to put in. The only possible way is from underneath engine with the O2 sensor connection temporary removed. A straight long nose plier is a must to get this in. Even when removing this is a very helpful tool.
- Could not get all air out of coolant system when refilling. Solved by driving front of car up on ramps and squeezing rad and heater hoses.
- All tools needed are 10, 12 and 14mm in various forms. In the belt area, there are 50-60mm of free space to body, and that is very little when working with sockets, so various keys must be used and they will slow you down.