Engine Trouble 1974 corvette
Thread Starter
Instructor
Joined: Jan 2017
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Engine Trouble 1974 corvette
Im having trouble starting my car. The engine turns over fine and it is getting gas, but the car just wont start. It keeps turning over and nothing happens. What else could make it difficult to start the car?
Pro
Joined: Jan 2017
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From: Beaver County PA
There are many reasons a motor won't start. As mentioned, no spark is probably the most common. Did you do something to the motor or did you just go out into the garage one day and had this problem? How was it running the last time you drove it? We need more info on the events leading up to this point.
Team Owner
Joined: Jan 2006
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From: Crossville TN
Air...fuel....spark are all needed. And, they are needed in the correct amounts and at the right time. Simple enough 
You can put a timing light on your engine and check timing as the car is [merely] cranking. This can rule out 'spark' and 'spark timing'. If you get no light flashes as the engine cranks, you are getting no spark.
IMO, your most likely problem is a bad condenser (if you still have points) or an electronic ignition module, if you don't.
You can put a timing light on your engine and check timing as the car is [merely] cranking. This can rule out 'spark' and 'spark timing'. If you get no light flashes as the engine cranks, you are getting no spark.
IMO, your most likely problem is a bad condenser (if you still have points) or an electronic ignition module, if you don't.
Team Owner
Joined: Jan 2006
Posts: 37,637
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From: Crossville TN
Points ignition systems and electronic ignition systems have their PLUSES & MINUSES. Electronic systems are trouble free and require no maintenance...UNTIL THEY FAIL. Then, you replace it with another one. If you have a spare with you, great; if you don't, you walk home.
Points require yearly maintenance and replacement every few years (big deal). When they start to deteriorate, you know it from the firing "misses" on occasion. But, you still can drive the car for a significant amount of time before the engine will not run.
Go with what works best for you.
Points require yearly maintenance and replacement every few years (big deal). When they start to deteriorate, you know it from the firing "misses" on occasion. But, you still can drive the car for a significant amount of time before the engine will not run.
Go with what works best for you.
Is my vette stock?? HAHA
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pull a plug and see if its flooded and the plug fouled, take off the air cleaner, hold open the choke and give it a full pull on the accelerator and see if you get a shot of gas into the carb from the accelerator pump. Put a meter on the coil + side and see if you have 12 volts when your cranking the motor. then pull a plug and check for spark at the plug. If you have gas, and spark and its not flooded, then try and check the timing like was stated above in #4 post. if your timing isnt on then your timing chain jumped and it needs to be replaced and realigned. that happened to me on my work truck. it jumped when I shut it off one day. Wouldnt start 1/2 hour after I shut it off.
Last edited by Rescue Rogers; May 4, 2017 at 10:19 PM.
Drifting
Joined: Jun 2005
Posts: 1,950
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From: Chino Hills CA
[QUOTE=7T1vette;1594665055]Air...fuel....spark are all needed. And, they are needed in the correct amounts and at the right time. Simple enough
Don't forget air, fuel, spark, and COMPRESSION in the correct amounts and the right time.
Don't forget air, fuel, spark, and COMPRESSION in the correct amounts and the right time.
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Thread Starter
Instructor
Joined: Jan 2017
Posts: 175
Likes: 14
There are many reasons a motor won't start. As mentioned, no spark is probably the most common. Did you do something to the motor or did you just go out into the garage one day and had this problem? How was it running the last time you drove it? We need more info on the events leading up to this point.
Thread Starter
Instructor
Joined: Jan 2017
Posts: 175
Likes: 14
pull a plug and see if its flooded and the plug fouled, take off the air cleaner, hold open the choke and give it a full pull on the accelerator and see if you get a shot of gas into the carb from the accelerator pump. Put a meter on the coil + side and see if you have 12 volts when your cranking the motor. then pull a plug and check for spark at the plug. If you have gas, and spark and its not flooded, then try and check the timing like was stated above in #4 post. if your timing isnt on then your timing chain jumped and it needs to be replaced and realigned. that happened to me on my work truck. it jumped when I shut it off one day. Wouldnt start 1/2 hour after I shut it off.
I checked and plugs are not flooded, when i press the accelerator i can smell the fuel fumes so its getting fuel. And i have been getting 12 volts when i try to start it.
like you said I Think the timing may be off.
How do i check the timing?
Le Mans Master
Joined: Jan 2001
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From: Dryden MI
Youtube is your friend on many repairs. Here is an example of a 350 timing procedure.
Last edited by Cooter Tech; May 5, 2017 at 06:54 PM.
Is my vette stock?? HAHA
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How many miles on the motor? You can pull all the plugs and crank the motor around until the rotor is at the number two tower on the distributor cap, then use a dowel to check how far down in the cylinder #1 piston is. you can also put a bit of rope in the cylinder number 1 as well leaving a tail out so you dont lose it in there, then use a socket on the crankbolt and slowly crank it clockwise and check the position of the cylinder as you get closer to the #1 tower. as you pass the center of the tower it should peak quickly. If you have the right amount of rope it will top out and stop turning when you are at the center of the tower or just off center. anything before or after means the chain jumped. Like I said, it happened to me on an old motor right after I shut it off. I just put in a new chain and timed it correctly, it started right up
Last edited by Rescue Rogers; May 5, 2017 at 07:20 PM.
Instructor
Joined: Jan 2017
Posts: 150
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From: mountains of N.E. Georgia Georgia
This happened to me once with a Chevelle. It was a bad ground strap from the engine to the firewall. I've only owned my Vette since December but I've learned no matter what is wrong with a Vette, the answer is always either a ground or vacuum problem. I'd start with the engine ground then I'd check the vacuum even though vacuum has nothing to do with the engine starting! 
Good Luck!
Good Luck!
Last edited by tomvr; May 5, 2017 at 07:29 PM.
Pro
Joined: Jan 2017
Posts: 653
Likes: 51
From: Beaver County PA
Do you have a points distributor or an HEI? If you have an HEI the module could be bad inside the cap. You can pull it out and take it to an Auto Zone or Advanced Auto to be tested. They can go bad without any warning.
Thread Starter
Instructor
Joined: Jan 2017
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How many miles on the motor? You can pull all the plugs and crank the motor around until the rotor is at the number two tower on the distributor cap, then use a dowel to check how far down in the cylinder #1 piston is. you can also put a bit of rope in the cylinder number 1 as well leaving a tail out so you dont lose it in there, then use a socket on the crankbolt and slowly crank it clockwise and check the position of the cylinder as you get closer to the #1 tower. as you pass the center of the tower it should peak quickly. If you have the right amount of rope it will top out and stop turning when you are at the center of the tower or just off center. anything before or after means the chain jumped. Like I said, it happened to me on an old motor right after I shut it off. I just put in a new chain and timed it correctly, it started right up
This motor is a 350 crate motor put in around 4 years ago and i would say it has around less than 10,000 miles put on it.
Is my vette stock?? HAHA
Joined: Oct 2015
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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with only 10,000 miles the timing chain idea of mine is pretty low odds. The idea about the HEI pickup might be feasible if you have HEI
Thread Starter
Instructor
Joined: Jan 2017
Posts: 175
Likes: 14
pull a plug and see if its flooded and the plug fouled, take off the air cleaner, hold open the choke and give it a full pull on the accelerator and see if you get a shot of gas into the carb from the accelerator pump. Put a meter on the coil + side and see if you have 12 volts when your cranking the motor. then pull a plug and check for spark at the plug. If you have gas, and spark and its not flooded, then try and check the timing like was stated above in #4 post. if your timing isnt on then your timing chain jumped and it needs to be replaced and realigned. that happened to me on my work truck. it jumped when I shut it off one day. Wouldnt start 1/2 hour after I shut it off.
I attached two pictures below, hopefully you can view them. I opened my hood up and checked the stainless steel line going to the carburetor and it is almost full of fuel, i think this is why my car wont start.
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,212
Likes: 9,352
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
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what kind of carb are you using? holley or edelbrock