Alternator Problem - Alfa Romeo Bulletin Board & Forums

 
LinkBack Thread Tools Display Modes
post #1 of 5 (permalink) Old 03-20-2017, 11:15 AM Thread Starter
Registered User
 
dj91alfa's Avatar
 
Join Date: Aug 2010
Location: Nashville, TN
Posts: 11
Alternator Problem

My S4 spider will frequently have a squeal from under the hood. At that time the all dash lights will come on and the radio will go off. Also, the voltage gauge will peak to max.
Would this indicate an alternator problem or possible wiring problem?

Thanks
dj91alfa is offline  
Sponsored Links
Advertisement
 
post #2 of 5 (permalink) Old 03-20-2017, 11:56 AM
Registered User
 
spiderserie4's Avatar
 
Join Date: Jul 2011
Location: Cologne, Germany
Posts: 5,259
How is the alternator charging? Put a voltmeter across the battery poles with engine ticking over: what voltage do you get? (don't go by the dash gauge for this)
Check battery ground is tight, also where it bolts to the trunk floor.

voltage regulator? it might even squeal if the brushes are really worn....
it is screwed in the back of the alt. itself, comes out easy with 2 screws (easy to get to, if you take off the air cleaner top half)

do a visual check, see if the brushes are long enough, and of even length, or oily perhaps...or worn right down.

Orig. Bosch regulator (Bosch 1 197 311 028) is probably 30$ to replace, same as Audi, BMW, Volvo what have you...

Dom - Alfa Spider 1990 S4 - formerly: Alfa 101 Sprint, 2600 Sprint, Montreal - family classics: Jensen Interceptor II, '58 Hooper RR Silver Cloud I, Shadow II, '60 Corvette.
spiderserie4 is offline  
post #3 of 5 (permalink) Old 03-20-2017, 12:12 PM Thread Starter
Registered User
 
dj91alfa's Avatar
 
Join Date: Aug 2010
Location: Nashville, TN
Posts: 11
The voltage on the battery is 12.6V prior to starting.
The voltage across the battery is approx. 13.6v when started.
I have seen it spike up to 18v while running.

Thanks for your help.
dj91alfa is offline  
 
post #4 of 5 (permalink) Old 03-20-2017, 12:23 PM
Registered User
 
spiderserie4's Avatar
 
Join Date: Jul 2011
Location: Cologne, Germany
Posts: 5,259
Quote:
Originally Posted by dj91alfa View Post
The voltage on the battery is 12.6V prior to starting.
The voltage across the battery is approx. 13.6v when started.
I have seen it spike up to 18v while running.

Thanks for your help.
those are all good values.
......except the 18V spike! thats a bad'un!

I'd get the alternator checked (Autozone do that for free, don't they...hoping you buy one of their alternators!....

could try the regulator first, but could well be a bad alt. diode.

Dom - Alfa Spider 1990 S4 - formerly: Alfa 101 Sprint, 2600 Sprint, Montreal - family classics: Jensen Interceptor II, '58 Hooper RR Silver Cloud I, Shadow II, '60 Corvette.
spiderserie4 is offline  
post #5 of 5 (permalink) Old 03-20-2017, 01:37 PM
Registered User
 
Alfajay's Avatar
 
Join Date: Jan 2005
Location: San Juan Capistrano
Posts: 7,853
Quote:
Originally Posted by spiderserie4 View Post
those are all good values.
......except the 18V spike! thats a bad'un!

I'd get the alternator checked (Autozone do that for free, don't they...hoping you buy one of their alternators!....

could try the regulator first, but could well be a bad alt. diode.
Yes, all true.

The key is to do something NOW. 18V is high enough to damage your EFI computer, radio, and anything else electronic. Is the tachometer electronic in an S4? If so, that could get fried too.

Jay Mackro
San Juan Capistrano, CA

'63 Guilia spider
'65 Guilia Sprint GT
'67 Duetto
'91 164L
Alfajay is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Alfa Romeo Bulletin Board & Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 
Replace with
For the best viewing experience please update your browser to Google Chrome