1978 engine won't turn over after tune up
Thread Starter
Heel & Toe
Joined: Apr 2013
Posts: 21
Likes: 1
From: Amherst Ohio
1978 engine won't turn over after tune up
Did a complete tune-up, plugs/wires/dist. Cap/ rotor! Had to drop starter out to simplify changing the plug wires and getting at the heat shields. All back together now and engine won't turn over? Battery fully up, not that! Have all electrical when key is in the ignition but when you turn the key to start the engine it seems it all goes dead! Seems to have a rather significant drain on the battery when turning the key to the start position. No "clicking" No "Nothing" when turning the key to start. It all ran fine before the tuneup? Need to start the trouble shooting but figure I'd get some ideas before hand. Thanks.
Emerging Vendor
Joined: Mar 1999
Posts: 1,599
Likes: 114
From: San Diego CA
Did a complete tune-up, plugs/wires/dist. Cap/ rotor! Had to drop starter out to simplify changing the plug wires and getting at the heat shields. All back together now and engine won't turn over? Battery fully up, not that! Have all electrical when key is in the ignition but when you turn the key to start the engine it seems it all goes dead! Seems to have a rather significant drain on the battery when turning the key to the start position. No "clicking" No "Nothing" when turning the key to start. It all ran fine before the tuneup? Need to start the trouble shooting but figure I'd get some ideas before hand. Thanks.
I'd check this first.
Greg
Thread Starter
Heel & Toe
Joined: Apr 2013
Posts: 21
Likes: 1
From: Amherst Ohio
Le Mans Master
Joined: Aug 2006
Posts: 7,431
Likes: 1,561
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
Stick or automatic?
At the starter, the purple wire connects to the small terminal closest to the block.
Is that how you connected it?
Your year may have the 'STARTER HARNESS EXTENTION'. Make sure the connection (behind the distributor) is good.
http://www.zip-corvette.com/77l-78-w...n-harness.html
Is that how you connected it?
Your year may have the 'STARTER HARNESS EXTENTION'. Make sure the connection (behind the distributor) is good.
http://www.zip-corvette.com/77l-78-w...n-harness.html
Last edited by Peterbuilt; Mar 20, 2016 at 03:27 PM.
Thread Starter
Heel & Toe
Joined: Apr 2013
Posts: 21
Likes: 1
From: Amherst Ohio
If they were reversed what would happen? I'm pretty sure that I didn't reverse these but then again anything is possible at this point. One thing I noticed is once the battery is completely charged and I turn the key to the start position it's like the car is out of park or in gear(neutral safety)! Absolutely nothing happens. If those wires were in fact reversed could that be the result? Also, it seems that when I do try and start the battery drains down right away. It's a brand new battery in the fall right before going into storage and I kept a trickle charger on it all winter. Now, if there is something wrong with the reinstall of the distributor cap and rotor that shouldn't cause the car to NOT turn over, right? My guess is the engine would still turn over just not start due to no spark? Am I correct here? Respect your advice! I'm rather confused on this one.
Thread Starter
Heel & Toe
Joined: Apr 2013
Posts: 21
Likes: 1
From: Amherst Ohio
At the starter, the purple wire connects to the small terminal closest to the block.
Is that how you connected it?
Your year may have the 'STARTER HARNESS EXTENTION'. Make sure the connection (behind the distributor) is good.
http://www.zip-corvette.com/77l-78-w...n-harness.html
Is that how you connected it?
Your year may have the 'STARTER HARNESS EXTENTION'. Make sure the connection (behind the distributor) is good.
http://www.zip-corvette.com/77l-78-w...n-harness.html
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Thread Starter
Heel & Toe
Joined: Apr 2013
Posts: 21
Likes: 1
From: Amherst Ohio
Thanks for confirming for me. Just now have to figure out if the solenoid extension harness was correctly connected. That's the only thing I can think of at this point. I'm pretty sure I did that correctly but I am trying to find a schematic that shows the correct way to hook up the ext. harness on my '78.
Le Mans Master
Joined: Aug 2006
Posts: 7,431
Likes: 1,561
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
When you turn the key to start the ignition switch stops sending power to most everything so the starter gets full battery voltage.
With the key in start battery voltage is sent from the ignition switch -through the neutral safety switch and to the small terminal on the starter solenoid. The solenoid then turns ON the starter.
So seeing the power go off with the key in'START' is normal.
So to answer your question if the connection at the 'starter extension' is bad 12 volts will stop there and the engine will not turn over.
Heres all the diagrams:
http://www.vetteprojects.com/bmv/mis...ng%20Diagrams/
