Cadillac Owners Forum banner

1 - 6 of 6 Posts

·
Registered
84 Seville
Joined
·
4 Posts
Discussion Starter #1
Hi all, I have searched around and there are a few different "ideas" yet I would like to be lead down the correct path. Son's 84 Seville started flashing lights, loss of power and eventually died.. Of course Batt was dead.. I charged, ran fine for a day and then dead again.. Obviously an ALT issue.. I replaced the ALT and belt.. Has been running fine for last 2 weeks and then today all of the sudden it starts happening again. Symptoms mimic the alt not charging the batt, system eventually drains batt and symptoms start once again.. No power, blinking dash lights etc.. This is the 4.1.. Clean car.. Son is frustrated but its just to clean to part with in my opinion. Thanks in advance for your advice.

Reid
 

·
Master of the Dark Art of Diagnostics
2003 DHS - two-2002 DHS, 2003 SLS, 1995 Sedan DeVille, 1989 Coupe DeVille
Joined
·
19,506 Posts
Hi all, I have searched around and there are a few different "ideas" yet I would like to be lead down the correct path. Son's 84 Seville started flashing lights, loss of power and eventually died.. Of course Batt was dead.. I charged, ran fine for a day and then dead again.. Obviously an ALT issue.. I replaced the ALT and belt.. Has been running fine for last 2 weeks and then today all of the sudden it starts happening again. Symptoms mimic the alt not charging the batt, system eventually drains batt and symptoms start once again.. No power, blinking dash lights etc.. This is the 4.1.. Clean car.. Son is frustrated but its just to clean to part with in my opinion. Thanks in advance for your advice.

Reid
=======================
have the battery load tested -
a bad battery could have killed the original alternator - and the new one -

another possibility is a defective new alternator -

PLEASE don't tell us it is from autozone -

bad grounds - corroded connections - broken wires are always a possibility -
when dealing with a 30+ year old car -
 

·
Registered
84 Seville
Joined
·
4 Posts
Discussion Starter #3
Ya I restore classics so know the ins and outs of well 50+ year old cars.. True the alt could possibly have been taken out by the batt, just something that is not common place. Yet because its draining the batt, it should not be that ecm reset I have read about.. Just was not sure if this was something that was known and has happened or if its just the charging/batt system itself over something else possibly causing the issue.. Never seen a car freak out like this dash lights flickering all over, power loss etc.. just odd symptoms that made me believe computer control issue. Locally I only purchase my parts from a speed shop first off, second Napa.. although some of their stuff is now chinesium also.
 

·
Registered
1926 Model T street rod, 2000 Jaguar XJ8, 1999 Corvette.
Joined
·
6,738 Posts
I've posted this MANY times. This engine has a poor belt routing. If the smog pump belt is loose it will slip on the water pump pulley at any RPM above idle, eventually causing the alternator to slow down and not provide sufficient amperage to charge the battery. Try turning the alt. pulley against normal rotation, engine off,by hand! If you can rotate it, the smog belt is too loose. Notice that the alt. belt only wraps around the one water pump pulley. If you look straight down at the pulley while you rotate the alt. you'll see the smog pump belt, if loose, will not move but the alternator to w/pump belt will. This belt must be tightened from under the car with extensions to reach past the front crossmember. Every 4100 powered car I've owned required that belt be tightened or replaced.
 

·
Registered
1926 Model T street rod, 2000 Jaguar XJ8, 1999 Corvette.
Joined
·
6,738 Posts
WHY??? asks for help then disappears! Either he or the car died!
 
1 - 6 of 6 Posts
Top