Announcement

Collapse
No announcement yet.

Alternator Problem/Electrical Short

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Alternator Problem/Electrical Short

    Howdy. It's been a long time since I posted. I'm still driving my '88 carby Festiva.

    I have a problem with the bearings going out on my alternators. I've replaced it 4 times under warranty from O'Reilly. Every time the bearing goes out. Someone suggested I may have a short going to ground through the bearings.

    I know I have a short somewhere. I installed a battery disconnect switch years ago. If i don't shut the switch off, the battery will drain within a couple of days. Now I'm thinking the short, and the alternator bearing failure are related.

    The two prong connector that goes in the back of the alternator broke. I have two insulated quick disconnects in it's place.

    Any suggestions on what to do?
    '88 Festiva L, stock carby engine (with exhaust upgrade), 4 speed tranny. Aspire Struts and Springs, Capri 14" wheels, interior gutted, battery in back

    '92 Geo Metro XFi

    '87 Suzuki Samurai

    '85 F150, modded 300cid

  • #2
    Diag the power draw first. Also, are you correctly tightening the alt belt? Excessive tention can cause premature bearing failure.
    Trees aren't kind to me...

    currently: 2 88Ls (Scrappy and Jersey), 88LX, 90L(Pepe), 91L, 91GL (Skippy) 93 GL Sport (the Mighty Favakk), 94 (Bruce) & 95 Aspire SEs, 97 Aspire (The Joker),
    94 Justy 4WD, 87 Fiero GT, plus 2 parts cars. That's my fleet.

    Comment


    • #3
      Your alternator is working very hard trying to keep the battery fully charged wearing out the bearings. Bet your gas milage and power is down too. Find that discharge!

      Comment


      • #4
        Do you have a voltage gauge in car?

        Sent from my SM-G900V using Tapatalk

        Comment


        • #5
          I have a volt meter in the car. It reads around 14v when the battery is charging, drops to 12.5 after it's charged.

          Regarding belt tension, I just use hand pressure to pull the alt back when I tighten the bolt. It will squall if I leave any slack in the belt.

          i'm not sure how to diagnosis the drain. It's in the harness somewhere.

          Thanks for the help!
          Last edited by BigElCat; 04-20-2016, 10:45 AM.
          '88 Festiva L, stock carby engine (with exhaust upgrade), 4 speed tranny. Aspire Struts and Springs, Capri 14" wheels, interior gutted, battery in back

          '92 Geo Metro XFi

          '87 Suzuki Samurai

          '85 F150, modded 300cid

          Comment


          • #6
            Originally posted by BigElCat View Post
            I have a volt meter in the car. It reads around 14v when the battery is charging, drops to 12.5 after it's charged.

            Regarding belt tension, I just use hand pressure to pull the alt back when I tighten the bolt. It will squall if I leave any slack in the belt.

            i'm not sure how to diagnosis the drain. It's in the harness somewhere.

            Thanks for the help!
            You'll need an amp gauge in line between the battery and the battery cable. Them start pulling fuses until you see a big drop.

            Sent from my SM-G900V using Tapatalk

            Comment


            • #7
              Belt tension is measured by deflection. I lay a straight edge across the top of the two pulleys (alternator and water pump) then push down on the middle with the end of a ruler and read the deflection. I think it's 5/8" for a used belt, slightly less for new. Deflection is given in Haynes manual and I've seen it in this forum. I have scratched a line in the alternator and housing to use as a guide and it's never far off.
              Original owner of silver grey carburetted 1989 Festiva. 105k km as of June 2006. 140k km as of June 2021.

              Comment


              • #8
                I've had 3 Festiva's with constant battery drain; one was due to the ignition switch not turning all the way to the off position, the other 2 were both due to previous owners not wiring the radios properly. If you have an upgraded stereo system like most do, that might be a good place to start.

                Comment


                • #9
                  I failed to mention that I had changed the water pump before I decided the bearings were bad in the alternator. The new pump didn't help with the squalling noise.

                  It turns out that the bearings were not bad in the alternator. I stiffed O'Reilly for a replacement alternator. My bad.

                  I put the new alternator on with a new v-belt. It was still squalling. I used a pry bar on the front section of the alternator to get more tension on the belt. This eliminated the squall, but I still had a persistent loud chirping noise. This chirping noise had been there prior to changing the pump and alternator. I put a spare set of pulleys on the pump and crank...the noise was still there.

                  I used a syringe to put several tablespoons worth of 30 weight motor oil into the relief hole in the water pump. Voila ! The noise is gone. I was tempted to try this sooner, but I've heard that it is the wrong thing to do. It seems to have been the cure. I'll post back if I have any problems with this 'trick'.
                  '88 Festiva L, stock carby engine (with exhaust upgrade), 4 speed tranny. Aspire Struts and Springs, Capri 14" wheels, interior gutted, battery in back

                  '92 Geo Metro XFi

                  '87 Suzuki Samurai

                  '85 F150, modded 300cid

                  Comment


                  • #10
                    Originally posted by WmWatt View Post
                    Belt tension is measured by deflection. I lay a straight edge across the top of the two pulleys (alternator and water pump) then push down on the middle with the end of a ruler and read the deflection. I think it's 5/8" for a used belt, slightly less for new. Deflection is given in Haynes manual and I've seen it in this forum. I have scratched a line in the alternator and housing to use as a guide and it's never far off.
                    I don't see any way to measure deflection. I can't get a straight edge under the front motor mount.
                    '88 Festiva L, stock carby engine (with exhaust upgrade), 4 speed tranny. Aspire Struts and Springs, Capri 14" wheels, interior gutted, battery in back

                    '92 Geo Metro XFi

                    '87 Suzuki Samurai

                    '85 F150, modded 300cid

                    Comment

                    Working...
                    X