1976 Stingray Oil issue
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6th Gear
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1976 Stingray Oil issue
I have a 1976 Stingray c3, I bought from a guy and it had some old sludgy oil in it, but the engine purred. I drained the oil and removed old filter. I was told by a guy at the AutoZone that I could/should use a synthetic blend oil in this car. I took his advice and used the synthetic blend. I started the car and it began to smoke and bubbled up at the header. I immediately shut the car off. I am worried my engine is ruined.The car had no issues before this, no leaks or smoking issues at all. Should I drain this oil out and put regular oil in it? I hope I have not ruined my engine. HELP!
Le Mans Master
Joined: Oct 2006
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From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Where exactly did the smoke/bubbles come from? Could it be from a few drips on the exhaust? Nothing wrong with semi-synthetic oil (blend). One thing that I have seen is a full synthetic oil running out of seals that were old and had some crud on them that the full synthetic washed out. But that was no where near immediate= took weeks.
Melting Slicks
Joined: Oct 2012
Posts: 2,156
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From: Dunedin NZ.
Are you sure you didn't spill some oil there when you were refilling the engine with oil? Was there any smoke coming out the exhaust?
FWIW it would probably have been a good idea to put an engine flush treatment through the engine if the original oil was so old and sludgy.
FWIW it would probably have been a good idea to put an engine flush treatment through the engine if the original oil was so old and sludgy.
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Thread Starter
6th Gear
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Team Owner
Joined: May 2001
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From: Western NY
I have a 1976 Stingray c3, I bought from a guy and it had some old sludgy oil in it, but the engine purred. I drained the oil and removed old filter. I was told by a guy at the AutoZone that I could/should use a synthetic blend oil in this car. I took his advice and used the synthetic blend. I started the car and it began to smoke and bubbled up at the header. I immediately shut the car off. I am worried my engine is ruined.The car had no issues before this, no leaks or smoking issues at all. Should I drain this oil out and put regular oil in it? I hope I have not ruined my engine. HELP!
Therefore, for that issue alone, you need to use a different oil. Unfortunately, the EPA has leaned on the oil manufacturers to take the ZDDP out of their "mass marketed" oil, in order to preserve the life of catalytic converters, even though it will damage older, flat tappet engines.
If you can't find a conventional oil that is "SL" rated, then use a conventional oil, and add a bottle of STP. The current bottles of STP claim that their formula has additional ZDDP in it. If you'd prefer a syn oil, then Amsoil and Joe Gibbs Racing have oils that are suitable for flat tappet engines (higher ZDDP levels).
With respect to your smoking issue, you most likely spilled some oil on the manifold, and it's simply burning off, unless you managed to somehow disturb the manifold, as "jb78L-82" suggested.
Last edited by leadfoot4; Feb 15, 2017 at 08:00 AM.
Thread Starter
6th Gear
Joined: Feb 2017
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Are you sure you didn't spill some oil there when you were refilling the engine with oil? Was there any smoke coming out the exhaust?
FWIW it would probably have been a good idea to put an engine flush treatment through the engine if the original oil was so old and sludgy.
FWIW it would probably have been a good idea to put an engine flush treatment through the engine if the original oil was so old and sludgy.
Le Mans Master
Joined: Oct 2007
Posts: 7,455
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From: RI, Now Franklin/Nashville TN
What color was the smoke? Blue, white, black?
Just an FYI that ZDDP was reduced by the EPA since cats need to last mandated by the EPA, I believe to 100,000 miles or 150K(? can't remember which mileage) where previously the cat only had to last 50K miles. High zinc oil will not kill your cat instantly but will shorten its life a little, like lasting 80K miles instead of 100K. Another example of the government saving us from ourselves....
Just an FYI that ZDDP was reduced by the EPA since cats need to last mandated by the EPA, I believe to 100,000 miles or 150K(? can't remember which mileage) where previously the cat only had to last 50K miles. High zinc oil will not kill your cat instantly but will shorten its life a little, like lasting 80K miles instead of 100K. Another example of the government saving us from ourselves....
Last edited by jb78L-82; Feb 15, 2017 at 09:09 AM.
Le Mans Master
Joined: Oct 2007
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From: RI, Now Franklin/Nashville TN
Every car I own blows white smoke (condensation) at start up...missed that. He would have to let it get to operating temp to see if it clears, otherwise maybe head gasket but doubt it that quick...after an oil change.
Le Mans Master
Joined: Aug 2005
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From: Temple Terrace Florida
Oil
You can use 10-40 Rotella oil for diesel engines. It has the necessary ZDDP in it for flat tappet cam protection. Any auto store should carry it. As for an engine flush, add a pint or two of Marvel Mystery Oil (don't overfill) to the crankcase and drive for 100 miles or so and change your oil as you normally would. That should do it. Jerry
Le Mans Master
Joined: Oct 2007
Posts: 7,455
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From: RI, Now Franklin/Nashville TN
You can use 10-40 Rotella oil for diesel engines. It has the necessary ZDDP in it for flat tappet cam protection. Any auto store should carry it. As for an engine flush, add a pint or two of Marvel Mystery Oil (don't overfill) to the crankcase and drive for 100 miles or so and change your oil as you normally would. That should do it. Jerry
"Contrary to the current internet buzz that diesel oil is the oil to use in a gasoline flat tappet cam engine, the correct oil to use on a continuous basis in your classic car's flat tappet cam engine is an oil designed for gasoline engines that contains the correct level of ZDDP anti-wear protection. Similarly, a race oil is not recommended for continued use in a street driven gasoline engine
Here are the differences between diesel engine oil and gasoline engine oil. In a modern diesel engine there is substantial exhaust soot contamination that the engine oil must contend with. Diesel oil is designed with much higher levels of detergency and dispersency to fight the soot contamination. Like ZDDP anti-wear chemistry, detergents are a surface active chemistry and compete directly for space on metal surfaces, such as the cam lobe and lifter face. So, in practice, the effective level of Zinc anti-wear is a bit lower than what we expect it to be based solely on chemical analysis. Additionally, the ZDDP that is generally used in diesel formulas is primary ZDDP (which activates at higher engine temperatures) since a diesel engine runs predominantly at operating temperature. In a gasoline engine, we must have both primary and secondary ZDDP (which activates at lower temperatures) since the engine will experience a significant number of cold starts. Also, the viscosity modifier polymers that are used in multi-viscosity engine oil to prevent viscosity loss at operating temperature (to protect the bearings) are different for diesel oil and gasoline oil. Diesels operate at essentially the same rpm all day long and need polymers that are shear stable to protect the bearings. Gasoline engines experience many large ranges of rpm during operation and require polymers that have both shear stability and thickening efficiency capability to protect the bearings."
Last edited by jb78L-82; Feb 15, 2017 at 09:42 AM.
Race Director
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questions
2. How many quarts of oil did you put in the engine?
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6th Gear
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He used 5 quarts of oil.