Too much oil? Should I drain?
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Car: 89' RS
Engine: 305
Transmission: 700r4
Too much oil? Should I drain?
Recently got an oil change for my 1989 rs. Its a 305 v8 5.0L engine. I checked the dip stick after i let it sit over night and it was about an inch above the full line. I know these engines are pretty resilliant, but should I worry about it?
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From: Davison, MI
Car: 89 Camaro
Engine: Dart SHP 400-Holley Terminator EFI
Transmission: Tremec T56 Magnum F
Axle/Gears: Strange S60 3.55:1
Re: Too much oil? Should I drain?
Too much oil can be as bad, or worse than, not enough.
To offer a tip,
It sounds like the oil change place is checking the oil wrong. The oil change place either put the wrong filter on, never checked level after fill, or more likely checked it right after engine shut off, failing to give the oil a few mins to make its way to the pan. If you wait 3-5 mins after shut down, then check it, you'll get better results.
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From: Richlands N.C.
Car: '92 RS
Engine: 350 carb'd
Transmission: T-5
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Re: Too much oil? Should I drain?
An inch over the full mark is a good amount. Like said above, drain it to the correct amount.
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Re: Too much oil? Should I drain?
That's most of a quart extra.
Take off the filter, drain it, put it back on, run the motor for a bit then turn it off, wait a few minutes and re-check.
Take off the filter, drain it, put it back on, run the motor for a bit then turn it off, wait a few minutes and re-check.
Re: Too much oil? Should I drain?
I disagree with the concept of waiting to check the oil level. A running engine holds possibly a pint in the lifter galley and head drains, unless it is horribly sludged. If it is that sludged, the engine will starve for oil.
Before citing any old wives' tales, colloquial resources, or other hearsay, consider the facts. A typical SBC or 60° V-6 holds just a little over four quarts in a full (stock) oil pan, not counting the 3/4 quart which is always in the filter. At 1,800 RPM cruising speed, the oil pump (operating at 900 RPM) will pump 14.88 quarts per minute (0.955 cubic inches per revolution). If the sump drops to 1½ quarts, the pump would draw enough air to ruin the engine in short order. In other words, the pump would suck the oil pan dry in about 6.05 seconds. If the oil did not drain back in less than 6 seconds, engines would last about a minute.
Now, how long should we wait to check the oil level?
Before citing any old wives' tales, colloquial resources, or other hearsay, consider the facts. A typical SBC or 60° V-6 holds just a little over four quarts in a full (stock) oil pan, not counting the 3/4 quart which is always in the filter. At 1,800 RPM cruising speed, the oil pump (operating at 900 RPM) will pump 14.88 quarts per minute (0.955 cubic inches per revolution). If the sump drops to 1½ quarts, the pump would draw enough air to ruin the engine in short order. In other words, the pump would suck the oil pan dry in about 6.05 seconds. If the oil did not drain back in less than 6 seconds, engines would last about a minute.
Now, how long should we wait to check the oil level?
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