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Discussion Starter #101
Have you had a chance to check the ignition timing.
Shoot for around 14° BTDC @ idle (vacuum advance disconnected).

If your engine is still backfiring thru the carb after the correct timing has been set, I recommend you purchase a spark plug piston stop and confirm TDC with the timing marks on the harmonic balancer and the timing tab lining up. There are a lot of articles and youtube videos on how to find TDC with a piston stop. We are also here to assist with advice as needed.

You should also do a compression check of all of the cylinders. Look for any cylinders with low/incosistant pressure. You may find some of your valves are out of adjustment... or even worse, the cam my have "wiped" a couple lobes.
I will look into it. On Saturday my father in law is coming over with a timing gun and done knowledge. He will help me with that.

As for compression test I can do that. What does it mean if the cam wiped a couple lobes?
 

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What does it mean if the cam wiped a couple lobes?
It means that one or more of your cam lobes has worn down and is not properly opening the valve. Usually, your engine would be running rough if the cam had one or more worn lobes.

You can always remove your valve covers and check all of your rocker arms for any play. I'm guessing your engine has a hydraulic cam... so there should be no play in any of the rocker arms (play = no clearance between the rocker arm and the pushrod & valve stem). If one or more of your rocker arms has any play, it is a "hint" that the cam lobe controlling that rocker arm may be worn down.

If none of the rocker arms have any play, you can also start your engine with the rocker arms still removed and watch the movement of all of the rocker arms. If one or more of the rocker arms seem to be moving much less than the others, that is also a sign that the cam may have worn lobes. Do not run the engine too long (or rev the engine) during this process... as some oil will leak onto the engine.
 

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Describe the backfire. Is it loud as hell? See flames? Or is it more of a cough out of the carb? Any backfiring out of the tailpipe? How knowledgeable is your father in law? I still think you should start a new thread mentioning you live in Chicago and need help. There are sure to be Nova owners around you who would probably be happy to help you with these issues but if they aren't following this thread they have no idea you live near them and need some help
 

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Discussion Starter #104
Describe the backfire. Is it loud as hell? See flames? Or is it more of a cough out of the carb? Any backfiring out of the tailpipe? How knowledgeable is your father in law? I still think you should start a new thread mentioning you live in Chicago and need help. There are sure to be Nova owners around you who would probably be happy to help you with these issues but if they aren't following this thread they have no idea you live near them and need some help
It's like a poof. No fire. No backfire from exhaust.

Father in law and grandfather in law are mechanics and know all about the SBC 350. They just haven't been able to make it out.

How do I post a video here?
 

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cool. the poof is most likely a fuel issue. Normally a timing issue is a loud bang and sometimes flame. Glad to hear you getting some help this weekend. Keep us posted.
 

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It really depends on your engines compression ratio. Higher compression engines (aprox 10:1 and higher) normally run the high octane gas.
To be on the safe side, use high octane gas (91-93) in your Nova until you get the engine to run decently. Once you have the engine running, carb adjusted, and the ignition timing set correctly... drive the car with the high octane and note how the car's performance feels.
On the next gas fill-up, try regular octane (87-89). If you do not notice any difference in the engine's performance and the engine does not "ping" while under load (slowly accelerating while going up hill), stick with the regular octane gas.
 

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I'm not sure if you have info listed in here about heads, cam, etc.; but I run 91 non-oxygenated on my 72 350 (stock with headers). This isn't for the octane rating as much as just for the lack of ethanol (we have a lot of stations that sell ethanol-free premium gas due to boats/atvs/outdoor equipment, so if you're in Chicago you might have a harder time finding it). According to the sticker on my radiator shroud I should be able to run lead-free 87 octane in my car if I stick with the stock specifications.

Unless the carb is setup to run gas with ethanol and the rest of the fuel system was changed to be ethanol-safe, I would try finding non-ethanol gas. Use Ethanol-free gas stations in the U.S. and Canada to find a station.
 

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Discussion Starter #109
I'm not sure if you have info listed in here about heads, cam, etc.; but I run 91 non-oxygenated on my 72 350 (stock with headers). This isn't for the octane rating as much as just for the lack of ethanol (we have a lot of stations that sell ethanol-free premium gas due to boats/atvs/outdoor equipment, so if you're in Chicago you might have a harder time finding it). According to the sticker on my radiator shroud I should be able to run lead-free 87 octane in my car if I stick with the stock specifications.

Unless the carb is setup to run gas with ethanol and the rest of the fuel system was changed to be ethanol-safe, I would try finding non-ethanol gas. Use Ethanol-free gas stations in the U.S. and Canada to find a station.
I couldn't find any remotely near me
 

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Discussion Starter #110
Ok so. I got all the lights working and have to install a new alternator (not charging).

I noticed brake fluid under back rear tire and so started to give it a brake job and both of the nuts on the lines into the cylinder are stripped and the lines are about to snap.

Sooooo.... I need to deal with this first. Off to learn how to bend brake tubing.
 

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Good to hear you got the lights working. They make special wrenches to fit the lines. Regular open end wrenches don't work well on them. You should be able to pick them up anywhere that sells tools. They will save you a lot of trouble loosening brake lines. Were the shoes worn when you took the drum off? You may just be able to replace the brake cylinder but if the pads got soaked you will be better off replacing them. The rear brake line should meet at a junction on the rear end. Measure the length and you can buy a replacement at any auto parts store. Was your FIL able to figure out what was going on with the engine?
 

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Discussion Starter #112
Good to hear you got the lights working. They make special wrenches to fit the lines. Regular open end wrenches don't work well on them. You should be able to pick them up anywhere that sells tools. They will save you a lot of trouble loosening brake lines. Were the shoes worn when you took the drum off? You may just be able to replace the brake cylinder but if the pads got soaked you will be better off replacing them. The rear brake line should meet at a junction on the rear end. Measure the length and you can buy a replacement at any auto parts store. Was your FIL able to figure out what was going on with the engine?
I tried to use a flare nut wrench but it was rounded off before I got to it. The line just snapped as I was trying to access the situation.

We started to do the timing and something came up and I ran out of fuel so it was the end of the day. I am going to rip out the old brake lines.
 

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Ok so. I got all the lights working and have to install a new alternator (not charging).
Turn your ignition key to the "Run Position" and do an "warning/idiot light" bulb check in the dash. Does the Alternator (ALT) light in the dash light up. If not, that could be the cause of your "No Changing" issue. The stock alternator for a 71 Nova needs the resistance of the Alternator bulb in the dash to "excite" the alternator to begin charging. If the alternator warning light bulb is burned out (or the wiring is not run correctly), the alternator will not charge.
 

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Discussion Starter #114
Turn your ignition key to the "Run Position" and do an "warning/idiot light" bulb check in the dash. Does the Alternator (ALT) light in the dash light up. If not, that could be the cause of your "No Changing" issue. The stock alternator for a 71 Nova needs the resistance of the Alternator bulb in the dash to "excite" the alternator to begin charging. If the alternator warning light bulb is burned out (or the wiring is not run correctly), the alternator will not charge.
Good to know. I would've changed the alt in a heartbeat!!
 

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Discussion Starter #115
So the brakes are done all the way around the car. New lines in the back. And the pedal feels great. Can't wait to see what the pedal feels like with the booster operating.

We started fiddling with the timing by rotating the distributor cap and the car grumbled and died. Started up and then died again.

I feel so dumb because I think the car ran out of fuel right as we were getting somewhere.

But.... Is it possible that doing the timing could've killed the engine? I don't know any better.

I filled the car up with gas and I filled the carb so I know the car has fuel. And it just won't start. How should I go about trouble shooting this?
 

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Discussion Starter #116
So the brakes are done all the way around the car. New lines in the back. And the pedal feels great. Can't wait to see what the pedal feels like with the booster operating.

We started fiddling with the timing by rotating the distributor cap and the car grumbled and died. Started up and then died again.

I feel so dumb because I think the car ran out of fuel right as we were getting somewhere.

But.... Is it possible that doing the timing could've killed the engine? I don't know any better.

I filled the car up with gas and I filled the carb so I know the car has fuel. And it just won't start. How should I go about trouble shooting this?
 

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To confirm if your getting power to HEI unit turn the ignition switch to on (not start). With circuit light check to see if power is going to HEI. If yes, then get someone to turn ignition to start while continuing to check for power going to HEI. Without power going to HEI during "start" motor will spin but not start. However when you release switch from start, in that instant car will sometimes start or spit back through carb. The times the car did start, was almost flooded and would not idle or run worth a flip. This was happening to me. Never figured out why I was loosing power to HEI when key was turned to start. Just one more thing to rule out.
 

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We started fiddling with the timing by rotating the distributor cap and the car grumbled and died. Started up and then died again.
But.... Is it possible that doing the timing could've killed the engine? I don't know any better.
Yes... turning the distributor in the wrong direction can "kill" you engine.
My guess is that you were turning the distributor cap (that is connected to the distributor body) in a clockwise direction when the engine died. Turning the cap in a clockwise direction "retards" your ignition timing... causing the idle speed to drop... until the engine dies.

Try turning the distributor cap a little bit in a counterclockwise direction and try to start the engine. If the engine does not start, turn the distributor cap a little bit more in a counterclockwise direction and try to start the engine again. Keep doing this until the engine starts.

Once you get the engine running, check your timing at idle. As mentioned previously in post #100, try to set your timing at around 14° BTDC @ idle (vacuum advance disconnected). My guess is that you will need to keep turning the distributor cap in a counterclockwise direction to achieve the correct timing.
Note: Once the engine is running and you turn the distributor cap in a counterclockwise direction, your engine RPMs will increase. Be sure to keep a flat blade screwdriver handy so you can adjust the idle speed (by turning the idle speed screw) while checking the ignition timing.

If your engine is still running rough after the correct timing has been set, I recommend you purchase a spark plug piston stop and confirm TDC with the timing marks on the harmonic balancer and the timing tab lining up (also recommended in post #100).
 

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Discussion Starter #119
Side project... Can I customize the length of my spark wires? They are a hott mess.

I've seen some kits but just wondering if I can reuse mine.

I also need to switch two wires fitting orientation but don't have the length to just swap the wires.
 

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There was a Warner Bros. rooster cartoon character, Foghorn Leghorn. He would say to the younger chick, "I say, I say pay attention son". Focus, if there is a plug wire on each plug to HEI, get the car running. Wire length can be easily addressed later.
 
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