Basic Ignition Troubleshooting
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Safety Car
Joined: Nov 2008
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From: Seattle Washington
Basic Ignition Troubleshooting
I have my newest Project Corvette and Im trying to start it for the first time. Near as I can tell it hasnt been started in 28 years or so. I apears to be a Crate Engine across the GM parts counter probably a LS6 variant with 1978 Casting Dates and 890 Heads. A Bore Scope shows no Rust in the Cylinders and nice Honing Marks.The bottom of the Engine is hardly dirty I doubt it was driven much at all. All the Cylinders are between 210 and 235 Compression and once warmed up the Rings and Valves might seat themselves and be even better. I took the Distributor out and pre lubed it and and after cleaning the Starter motor I have it turning over.
So Im at the point of starting it. When I first gave it a fog of starting fluid it popped telling me it had Ignition. Now that I have some fresh Gas to make it run I have no Ignition. I have an Inductive Timing Light and its showing nothing. I have 12 volts or more on both sides of the Coil. Cranking I still have 10.8. Putting the Timing Light on the Coil Wire isn't showing anything. The Tach Drive distributor has a Rotor and its turning wile Cranking. If I had another Coil laying around I would try that but I don't. Its been 30 years since I delt with one of these. I should probably file the Points and check the Capacitor. These old names are just coming back to me as I'm writing.
What is the Diagnostic Tree to follow from this point ?
So Im at the point of starting it. When I first gave it a fog of starting fluid it popped telling me it had Ignition. Now that I have some fresh Gas to make it run I have no Ignition. I have an Inductive Timing Light and its showing nothing. I have 12 volts or more on both sides of the Coil. Cranking I still have 10.8. Putting the Timing Light on the Coil Wire isn't showing anything. The Tach Drive distributor has a Rotor and its turning wile Cranking. If I had another Coil laying around I would try that but I don't. Its been 30 years since I delt with one of these. I should probably file the Points and check the Capacitor. These old names are just coming back to me as I'm writing.
What is the Diagnostic Tree to follow from this point ?
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Can you rotate the engine a small amount while measuring the voltage on the coil C- lead to see if the points are actually closing and electrically conductive?
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Take the wire off the points, with power on. Tap the wire quickly to a good ground. Coil should throw a spark. If yes, probably dirty points. If no, check the wiring and if good likely the coil
Race Director
Joined: Nov 2006
Posts: 13,068
Likes: 7,682
From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
2024 C3 of the Year Finalist- Modified
2022 C3 of the Year Finalist - Modified
Cruise-In VIII Veteran
Yeah, that'll do it!
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Team Owner
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From: Southern Cal Ca
St. Jude Donor '22
I have my newest Project Corvette and Im trying to start it for the first time. Near as I can tell it hasnt been started in 28 years or so. I apears to be a Crate Engine across the GM parts counter probably a LS6 variant with 1978 Casting Dates and 890 Heads. A Bore Scope shows no Rust in the Cylinders and nice Honing Marks.The bottom of the Engine is hardly dirty I doubt it was driven much at all. All the Cylinders are between 210 and 235 Compression and once warmed up the Rings and Valves might seat themselves and be even better. I took the Distributor out and pre lubed it and and after cleaning the Starter motor I have it turning over.
potential
