|
|
|
|
| Author |
|
|
Registered
Join Date: Jun 2004
Location: Sacramento, CA
Posts: 185
|
Battery Light
I have a 1988 911
Yesterday battery light came on intermittently at idle 750rpm , The care was warmed up and it was about 90 degrees out. On the way into work today lower temp, and no light at idle. What would have caused the light to go on in this fashion, battery, alternator, v-belt? Thank you for your time, SMC |
||
08-18-2005, 08:50 AM
|
|
|
Registered
Join Date: Aug 2005
Location: Commerce Twp, MI
Posts: 80
|
I have read in past posts that this means your alternator is "beginning"
to go bad. If this is the case, my alternator was beginning to go bad 4-5 years ago. In my case it only occured at idle, intermittenly , also . I would still check voltage with a volt meter and your belt however. Mine has not gone on at idle since I made some adjustments and installed a Steve Wong chip. My idle is at 900-950 rpms now. You might want to increase your idle speed a bit. When I had this problem mine was also around 700-750 rpms
__________________
1985 Carrera 1995 325is 2000 Grand Cherokee |
||
|
08-18-2005, 11:21 AM
|
|
|
Moderator
Join Date: Dec 2001
Posts: 9,569
|
Overheated voltage regulator. Happens in high temperatures.
Moving the VR to a location on the back of the alternator that's two inches above the engine case wasn't a very good idea. HEAT is the enemy of electrical components. Anyway, it might be time for a replacement VR, which is available from our host here. Figure an hour to remove the alternator and install the replacement regulator and hook everything back up. Tons of material in the archives here on this.
__________________
'66 911 #304065 Irischgruen ‘96 993 Carrera 2 Polarsilber '81 R65 Ex-'71 911 PCA C-Stock Club Racer #806 (Sold 5/15/13) Ex-'88 Carrera (Sold 3/29/02) Ex-'91 Carrera 2 Cabriolet (Sold 8/20/04) Ex-'89 944 Turbo S (Sold 8/21/20) |
||
|
08-18-2005, 11:33 AM
|
|
|
Registered
|
750 seems low; isn't the correct idle speed 850-900 RPM? If so, there may be nothing wrong with your charging system. i.e. if the RPM's are too low the alternator will simply not be producing enough current. I think the first thing to do is check/correct idle speed.
Jerry M '78 SC |
||
|
08-18-2005, 11:39 AM
|
|
|
Registered
Join Date: Aug 2005
Location: Commerce Twp, MI
Posts: 80
|
Thats I what was thinking Jerry. I had the same issue , same low idle, increased the idle, no more light. But SMC, if you must pull the alternator, it is a perfect time to polish / powder coat that fan ! (Lots of threads on that too : )
Mike
__________________
1985 Carrera 1995 325is 2000 Grand Cherokee |
||
|
08-18-2005, 11:49 AM
|
|
|
Registered
Join Date: Jun 2004
Location: Sacramento, CA
Posts: 185
|
Thank you for all the great advice. Just got the 88
My father and I are restoring a 1970 911 T, and this forum has been nothing but helpful!!!!!!!!!!!!!!! |
||
|
08-18-2005, 11:53 AM
|
|
|
1978 Porsche 911 SC 3.0
