1969 won’t start
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6th Gear
Joined: Jun 2021
Posts: 6
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1969 won’t start
Readers I have a 1969 corvette with the L46 350 engine. Recently I took the car for a short drive and after cutting it off, when I went to restart it I got nothing, the car appeared to not be getting any electrical power as the radio nor courtesy lights would come on. Tried boosting with another vehicle and still no power. Took the battery and had it checked, it was only 9 months old and they swapped it for a new one and upon installation it actually started the car. Just went to pull it out of the garage and it started just fine, but when I turned it off I got the same symptoms as before. I checked the battery cables and they appear tight and not corroded. Sorry for the long post but any suggestions would be greatly appreciated.
Safety Car
Joined: Mar 2006
Posts: 4,530
Likes: 5,113
From: Chester VA
Geno,
Welcome! Electrical problems are a pain; I feel for you.
Certainly sounds like an intermittent connection problem. Is your wiring harness firmly connected at the bulkhead connector located on the engine side of the firewall below your master cylinder and/or power booster? How about the connections on your horn relay (not sure where that is on a 69 - on a 72 it's on the driver's side wheelhouse)?
Has any electrical wiring work been done lately?
Larry
Welcome! Electrical problems are a pain; I feel for you.
Certainly sounds like an intermittent connection problem. Is your wiring harness firmly connected at the bulkhead connector located on the engine side of the firewall below your master cylinder and/or power booster? How about the connections on your horn relay (not sure where that is on a 69 - on a 72 it's on the driver's side wheelhouse)?
Has any electrical wiring work been done lately?
Larry
Drifting
Joined: Nov 2013
Posts: 1,546
Likes: 281
From: Scottsdale Arizona
Check the connection for your negative battery cable. It could be dirty or corroded since it’s out in the open below the battery box. I had a similar issue as yours and I actually ended up replacing the cables and no problems since then.
2026 Loser of the Year
Joined: Sep 2013
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From: New Or-leens Loo-z-anna
Use a Good voltmeter:
Check the new battery to see if it has 12volt minimum.
Check the voltage where the Positive cable bolts to the terminal on the starter for12volts minimum.
Check the voltage at the horn relay which is on the driver-fender well for 12volt minimum.
Check the voltage at the fuse block under the dash with the Ignition key turned to the ON position (the next position would be Start/Crank....do not turn the key that far)
Tell us your readings/results.
Check the new battery to see if it has 12volt minimum.
Check the voltage where the Positive cable bolts to the terminal on the starter for12volts minimum.
Check the voltage at the horn relay which is on the driver-fender well for 12volt minimum.
Check the voltage at the fuse block under the dash with the Ignition key turned to the ON position (the next position would be Start/Crank....do not turn the key that far)
Tell us your readings/results.
Is my vette stock?? HAHA
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From: Im not allowed to tell you
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Check your ground cable to the frame. Someone a while back with a similar issue had a cable that looked fine but was a little lumpy and they cut it open to find it was corroded completley on the inside.
then check your fusible links...you may have power at the battery but nothing going to the horn relay which is a bus bar for all your vehicle power...like Dorr gunner suggested
then check your fusible links...you may have power at the battery but nothing going to the horn relay which is a bus bar for all your vehicle power...like Dorr gunner suggested
Last edited by Rescue Rogers; Jun 30, 2021 at 10:16 PM.
Race Director
Joined: Jul 2015
Posts: 13,082
Likes: 3,399
From: SW Florida.
the neg cable at the frame is the issue. steel frame copper lug aluminum wire. then start shoving mass quantities of electrons through that joint. differential metal electrolysis. you never have to splash one drop of water on that spot and it will be corroded away. and the aluminum wire is toast up about 6 inches. why this cable gets like this and the one from engine block to frame doesn't is beyond me. i would guess that every bit of electricity that the car ever used passed through this connection. you can buy the 89 buck corvette one that has a big grommet on it to seal hole in batt box or buy the 12 buck one from auto parts store and goop it with silicone or some other non NCRS-points style seal. don't try to get the grommet off the old cable. you will hurt yourself.
Burning Brakes
Joined: Jan 2006
Posts: 1,223
Likes: 174
From: Fort Wayne IN
I agree, it is likely the battery cables. Get a set of jumper cables and go from the negative post of the battery, out the door, to a good point on the frame or transmission temporarily, and if it starts - that confirms the negative battery cable is the issue.
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Racer
Joined: Jul 2018
Posts: 428
Likes: 182
From: Green Bay WI
Had this same problem this week, just picked up the car from the shop today. It's a 72 and wouldn't start except with a push start. Everything checked out okay, battery, starter, alternator, etc., until we got to the negative battery cable. Upon examination the rubber casing holding the dozens of wires inside had split open and moisture must have gotten in there as there was all kinds of corrosion. Replaced the cable, 24 inch, and the car fired right up.