Help needed- Car doesn't start without a jump
Thread Starter
6th Gear
Joined: Mar 2018
Posts: 6
Likes: 0
Help needed- Car doesn't start without a jump
Hey guys, my dad passed down his 78 to me a couple days ago. Well I already ran into my first problem after a few years. The car does't want to start without getting a jump. However when I turn the key I can hear the starter going but no dice. I'd figure the battery is no good but its fairly new (I am thinking it a bad quality battery). I haven't had a chance to use an actual voltmeter yet. However the voltmeter in the car reads 11-12 volts when the key is in ignition. The car also has an electric fan installed with a manual on/off switch. When I flick it on, I notice the voltmeter drops to 8 and even the backlight on the radio dims. Could the wiring of the fan be part of the problem as well? Thanks in advance for any help!
Burning Brakes
Joined: Dec 2005
Posts: 992
Likes: 56
From: Baldwinsville, NY
Welcome, most 40 year old cars have some kind of battery drain that over time (days or weeks) will drain a battery. This is not good for any battery or electric system. You need to address that after you find out what you short term problem is.
The battery and or the alternator might be bad. Any auto parts store can test both.
After that you check that you have good wire connections, the list is endless.
Always start Electric repairs by disconnecting the negative battery connection first!
The battery and or the alternator might be bad. Any auto parts store can test both.
After that you check that you have good wire connections, the list is endless.
Always start Electric repairs by disconnecting the negative battery connection first!
Safety Car
Joined: Oct 2007
Posts: 3,729
Likes: 267
From: Austin Texas
Corvette of the Year Winner 2017
2016 C3 of Year Finalist
first thing verify every ground connection is clean and solid connection to metal frame.
do not just look, unbolt clean and veirify. frame ground to battery and verify the ground cable from frame to engine/starter.
If those are good,. My next suspect would be the main positive cable.
i would change the (50 year old) main +12 battery cable from
battery to starter. they frequently have internal corrosion inside the cable.
No one changes this cable, because it is a pain in the ***.
do not just look, unbolt clean and veirify. frame ground to battery and verify the ground cable from frame to engine/starter.
If those are good,. My next suspect would be the main positive cable.
i would change the (50 year old) main +12 battery cable from
battery to starter. they frequently have internal corrosion inside the cable.
No one changes this cable, because it is a pain in the ***.
Last edited by 69Vett; Mar 8, 2018 at 04:49 PM.
Team Owner
Joined: Jan 2007
Posts: 53,648
Likes: 878
From: Southern Cal Ca
St. Jude Donor '22
could be,,,
borderline starter
cables
battery
simple enough but time consuming.
11vdc is above starter min, but- many recon starters are not to spec
bat is easy to have tested
cables can be a pain to change.
borderline starter
cables
battery
simple enough but time consuming.
11vdc is above starter min, but- many recon starters are not to spec
bat is easy to have tested
cables can be a pain to change.
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
Hey guys, my dad passed down his 78 to me a couple days ago. Well I already ran into my first problem after a few years. The car does't want to start without getting a jump. However when I turn the key I can hear the starter going but no dice. I'd figure the battery is no good but its fairly new (I am thinking it a bad quality battery). I haven't had a chance to use an actual voltmeter yet. However the voltmeter in the car reads 11-12 volts when the key is in ignition. The car also has an electric fan installed with a manual on/off switch. When I flick it on, I notice the voltmeter drops to 8 and even the backlight on the radio dims. Could the wiring of the fan be part of the problem as well? Thanks in advance for any help!
Melting Slicks
Joined: Dec 2009
Posts: 3,229
Likes: 656
From: Thunder Bay
If the cars starts well with a jump, I think you can pretty much eliminate cables, grounds, and starter as potential problem areas. Check the connections at the battery and if they check out, its your battery.
What does the voltmeter read when its running. It should be around 14 volts if the alternator is working.
What does the voltmeter read when its running. It should be around 14 volts if the alternator is working.
Thread Starter
6th Gear
Joined: Mar 2018
Posts: 6
Likes: 0
Thanks for all the help guys! so I followed all advice so far doing as much as I can since its the day after the snow storm NY just had. I went to undo the connection to the battery and it seems the connection got "fused" to terminal on the positive side (banging head on A pillar).
Thread Starter
6th Gear
Joined: Mar 2018
Posts: 6
Likes: 0
If the cars starts well with a jump, I think you can pretty much eliminate cables, grounds, and starter as potential problem areas. Check the connections at the battery and if they check out, its your battery.
What does the voltmeter read when its running. It should be around 14 volts if the alternator is working.
What does the voltmeter read when its running. It should be around 14 volts if the alternator is working.
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Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,117
From: Crossville TN
If you connected the jumper cables to the battery terminals, I think that your battery is depleted. If the battery cables in your car were the problem, jumper cables still would not start the car.
If the car is going to sit for long periods of time. you should either connect a good trickle charger to the battery when stored or install a battery disconnect to one of the battery terminals and disconnect it when in storage.
Your battery MAY be fine, once it has had an opportunity to reach full-charge. Or, once charged, you may find similar issues with starting...and that would indicate the battery could no longer hold a charge.
If the car is going to sit for long periods of time. you should either connect a good trickle charger to the battery when stored or install a battery disconnect to one of the battery terminals and disconnect it when in storage.
Your battery MAY be fine, once it has had an opportunity to reach full-charge. Or, once charged, you may find similar issues with starting...and that would indicate the battery could no longer hold a charge.
Thread Starter
6th Gear
Joined: Mar 2018
Posts: 6
Likes: 0
If you connected the jumper cables to the battery terminals, I think that your battery is depleted. If the battery cables in your car were the problem, jumper cables still would not start the car.
If the car is going to sit for long periods of time. you should either connect a good trickle charger to the battery when stored or install a battery disconnect to one of the battery terminals and disconnect it when in storage.
Your battery MAY be fine, once it has had an opportunity to reach full-charge. Or, once charged, you may find similar issues with starting...and that would indicate the battery could no longer hold a charge.
If the car is going to sit for long periods of time. you should either connect a good trickle charger to the battery when stored or install a battery disconnect to one of the battery terminals and disconnect it when in storage.
Your battery MAY be fine, once it has had an opportunity to reach full-charge. Or, once charged, you may find similar issues with starting...and that would indicate the battery could no longer hold a charge.
Race Director
Joined: Jul 2015
Posts: 13,082
Likes: 3,399
From: SW Florida.
About time to pull it out now. Not for driving, just to chase bugs... batt cable fused to positive post? Probably just stuck on good and nasty corrosion blocking current flow. First place to straighten out.
Race Director
Joined: Mar 2017
Posts: 11,934
Likes: 4,497
From: Virginia
This is it exactly. It's always the battery, and these are classic battery symptoms.Take it back to wherever you bought it. They may be able to test it, replace it for free (it happens!) or at least pro-rate a replacement. Once it's replaced, you can check connections, etc.
Last edited by Bikespace; Mar 8, 2018 at 10:44 PM.