Engine oil and it's additives question
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Race Director
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From: Danville Illinois
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Engine oil and it's additives question
Say you have 1 quart of whatever, 10/40, straight 30 weight, or any of the probably 100 different variations of oil for engines.
Question is - do the additives added to the oil separate with age/time ?
My Uncle would empty half of the quart and them shake it and pour the rest in.
I bought a case of GM rear end posi fluid some 50 years ago and have two bottles left, why would i NOT shake the bottle before using it.
Yes or no answer, just keep it simple.
Question is - do the additives added to the oil separate with age/time ?
My Uncle would empty half of the quart and them shake it and pour the rest in.
I bought a case of GM rear end posi fluid some 50 years ago and have two bottles left, why would i NOT shake the bottle before using it.
Yes or no answer, just keep it simple.
Pro
Joined: Jul 2021
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yes, they will separate over time.
better yet, put the posi fluid in diff First ... then "rinse" the posi bottles w/ fresh gear oil and then that goes in diff.
rinse & repeat .................. basic chem lab 101-102 tech
better yet, put the posi fluid in diff First ... then "rinse" the posi bottles w/ fresh gear oil and then that goes in diff.
rinse & repeat .................. basic chem lab 101-102 tech
Is my vette stock?? HAHA
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Yes....The old stuff would seperate. I was trained to shake the cans before spiking them with the spout....does that tell you how long ago that was???? Not sure if the synthetic stuff would seperate but whats a few minutes of shaking a bottle, no loss
Dr. Detroit
Joined: Mar 2012
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From: New Braunfels Texas
About 12 years ago I did a "shed find" restoration on a 1980 BMW R100RT bike......it had been sitting in the shed since 1984...at that point, 26 years.......it only had 4000 miles on it and was in excellent condition considering.
After verifying the boxer would spin over by hand...... I drained the oil and it was very clear, but when I pulled the pan to inspect, there was a white, almost lithium greasy substance coating the bottom of the pan....about 1/8" thick........I determined that the additive package in this 26 year old oil had separated. It was not moisture or anything like that.......below the first layer of white was a grey almost moly looking paste (like cam lube!)......very slick to the finger. I cleaned everything, refilled, refurbed both Amal carbs.....fresh gas and lit it up.....no issues.
So yes.....oil additives packages do separate over time......
Sorry...no keep it simple yes or no this morning......story time.
Jebby
After verifying the boxer would spin over by hand...... I drained the oil and it was very clear, but when I pulled the pan to inspect, there was a white, almost lithium greasy substance coating the bottom of the pan....about 1/8" thick........I determined that the additive package in this 26 year old oil had separated. It was not moisture or anything like that.......below the first layer of white was a grey almost moly looking paste (like cam lube!)......very slick to the finger. I cleaned everything, refilled, refurbed both Amal carbs.....fresh gas and lit it up.....no issues.
So yes.....oil additives packages do separate over time......
Sorry...no keep it simple yes or no this morning......story time.
Jebby
Burning Brakes
Joined: Apr 2020
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From: Western NY
A few years back I read a Q&A article someone wrote with a guy from Penzoil and one of the questions they asked him was about shelf life of oil. I don't remember what he said about the max shelf life but I do remember him saying if it was sitting for 6 months or more to shake the oil because the additive package can separate from the oil.
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Before that it was a Purple Martin gas station that only had oil in 55 gallon drums, you pumped it into glass bottles and then to the customers car.
The owner would say win you get to the last 3 inches, switch barrels and save the rest for me.
Last edited by Mod75; Dec 17, 2021 at 11:48 AM.
