Help I have a sick 850
#1
Help I have a sick 850
My wife has been very patient her 850 broke an idler pulley changed that and then.....well, I went through 3 alternators and got the voltage back to 13.9 at start up thought all was good so I told her to take it to work. She got towed home it killed the battery the voltage has been beating me up. It must be something stupid like me but I can't get her to charge it's a 95 with 117K
#2
#3
also if you totally drained the battery when the alternator failed you may need to replace it. First check battery voltage with the engine off. Should be ~12.6V. Jump start the car and check the voltage at the battery with the engine running. Should be ~14V. Now turn on all your electrical loads - high beam, fan blower on hi, rear defrost etc. voltage should sustain over 13V at idle. If you can't retain the charge after running the car for 15 minutes, time for a new battery.
#6
I'd do two things - 1) check and make sure all terminals and connecters are clean and tight. 2) replace the overload relay (should be in the fuse box up by the firewall - owners manual should say which slot)
As background, there's not a lot of components in the charging system. First the alternator is really two things - its the generator "motor" plus a voltage regulator. If the generator or regulator's diodes fails you may get zero volts or something less than 13V. Typically you replace both with a new alternator so I don't suspect this is the problem. Side bar - Newer alternators use a voltage sensing lead to know if the system voltage requires the alternator to kick in - not sure what year that started with. Next you have your cabling. If the cable ends get corroded - either at the battery terminal, altnerator or starter motor, they will heat up and melt the insulation. best to check and see if your cabling is in good shape - no cracked or broken connectors etc. If there is more than a .2V drop between the two ends of a cable, you need to check grounds/terminals/connectors. Last part is the overload relay. Not sure where or which slot that's in but if it is old and sticky, time to replace.
As background, there's not a lot of components in the charging system. First the alternator is really two things - its the generator "motor" plus a voltage regulator. If the generator or regulator's diodes fails you may get zero volts or something less than 13V. Typically you replace both with a new alternator so I don't suspect this is the problem. Side bar - Newer alternators use a voltage sensing lead to know if the system voltage requires the alternator to kick in - not sure what year that started with. Next you have your cabling. If the cable ends get corroded - either at the battery terminal, altnerator or starter motor, they will heat up and melt the insulation. best to check and see if your cabling is in good shape - no cracked or broken connectors etc. If there is more than a .2V drop between the two ends of a cable, you need to check grounds/terminals/connectors. Last part is the overload relay. Not sure where or which slot that's in but if it is old and sticky, time to replace.
Last edited by mt6127; 04-15-2019 at 04:11 PM.
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