Topping up oil when engine still running
- Thread starter Vdubuk
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I think I added a couple times to the LTD back in the day, with it running, but not even close to warm, with oil that was as cold as what was in the sump. Nothing was doing much flying.
It was one of those toothpaste tube oil additions.
Originally Posted By: Garak
I think I added a couple times to the LTD back in the day, with it running, but not even close to warm, with oil that was as cold as what was in the sump. Nothing was doing much flying.
It was one of those toothpaste tube oil additions.
LTD was an 8 ?
Try it on a 4...
Just charted the Delta in crank case volume for 4, 6, and 8 cylinder engines (the percentage is the percentage change in crankcase volume as a percentage of cylinder volume) for 4, 6, and 8, 3" stroke, 5.7" rod length.
A 4 cylinder at TDC has two all the way up, and two all the way down. At 90 degrees, has the maximum rod angularity (think ladder sliding down wall), so has a significant change in crankcase pressure as the cylinders are all "more down" than they would be sinusoidally.
Sixes, along with perfect primary balance show the benefit of three phase electricity, and the 8 is marginally more lumpy.
Just saying.
I think I added a couple times to the LTD back in the day, with it running, but not even close to warm, with oil that was as cold as what was in the sump. Nothing was doing much flying.
LTD was an 8 ?
Try it on a 4...
Just charted the Delta in crank case volume for 4, 6, and 8 cylinder engines (the percentage is the percentage change in crankcase volume as a percentage of cylinder volume) for 4, 6, and 8, 3" stroke, 5.7" rod length.
A 4 cylinder at TDC has two all the way up, and two all the way down. At 90 degrees, has the maximum rod angularity (think ladder sliding down wall), so has a significant change in crankcase pressure as the cylinders are all "more down" than they would be sinusoidally.
Sixes, along with perfect primary balance show the benefit of three phase electricity, and the 8 is marginally more lumpy.
Just saying.
It was a four. It wasn't really an ordinary "add" at all, though. I squeezed as much of a quart in, out of a GTX bottle, and it was the consistency of toothpaste, with a beautiful -40 C day. I didn't know which would die first, the engine or me.
It wouldn't have splashed without a stick of dynamite.
Originally Posted By: Shannow
Nope, but blowby and crankcase pulsations (especially if a 4 cyl) will blow it up into your face.
Ask me how I know.
+1... I still have some oil spots on the hood liner from the one time I opened my fill cap while the engine was running to watch the cams on my Fusion...
Nope, but blowby and crankcase pulsations (especially if a 4 cyl) will blow it up into your face.
Ask me how I know.
+1... I still have some oil spots on the hood liner from the one time I opened my fill cap while the engine was running to watch the cams on my Fusion...
If your 4 cylinder car is idling at say 600 rpm, there are 2400 air compression events per minute from the underside of the pistons. That’s 40 per second. Kinda drafty.
Originally Posted By: Shannow
Originally Posted By: Snagglefoot
If your 4 cylinder car is idling at say 600 rpm, there are 2400 air compression events per minute from the underside of the pistons. That’s 40 per second. Kinda drafty.
Nope...it's twice per rev.
Nope. Once per rev. Watch carefully.
https://www.youtube.com/watch?v=OGj8OneMjek
Originally Posted By: Snagglefoot
If your 4 cylinder car is idling at say 600 rpm, there are 2400 air compression events per minute from the underside of the pistons. That’s 40 per second. Kinda drafty.
Nope...it's twice per rev.
Nope. Once per rev. Watch carefully.
https://www.youtube.com/watch?v=OGj8OneMjek
Originally Posted By: Vdubuk
Just out of interest,Any views on doing this guys..i dont mean from a health and safety perspective but from a mechanical point of view..is adding cold oil from top down detrimental
Put your oil in the microwave to warm it up if you are worried.
Just out of interest,Any views on doing this guys..i dont mean from a health and safety perspective but from a mechanical point of view..is adding cold oil from top down detrimental
Put your oil in the microwave to warm it up if you are worried.
As a kid we poured STP (the old honey consistency stuff) into a running engine and you could hear the lifters quiet down as it got circulated.
Originally Posted By: Snagglefoot
As a kid we poured STP (the old honey consistency stuff) into a running engine and you could hear the lifters quiet down as it got circulated.
Yes. That could be about the only time I could think of to top up the oil while the engine was running.
As a kid we poured STP (the old honey consistency stuff) into a running engine and you could hear the lifters quiet down as it got circulated.
Yes. That could be about the only time I could think of to top up the oil while the engine was running.
Originally Posted By: Snagglefoot
Originally Posted By: Shannow
Originally Posted By: Snagglefoot
If your 4 cylinder car is idling at say 600 rpm, there are 2400 air compression events per minute from the underside of the pistons. That’s 40 per second. Kinda drafty.
Nope...it's twice per rev.
Nope. Once per rev. Watch carefully.
https://www.youtube.com/watch?v=OGj8OneMjek
I see 2 air compression events under the pistons per revolution of the crankshaft. The first 180 degree crankshaft rotation has an air compression event from both #1 and #4 pistons moving down at the same time. The next 180 degree crankshaft rotation has an air compression event from both #2 and #3 pistons moving down at the same time. So there are 1200 air compression events in the crankcase per minute in an engine at 600 RPM.
Originally Posted By: Shannow
Originally Posted By: Snagglefoot
If your 4 cylinder car is idling at say 600 rpm, there are 2400 air compression events per minute from the underside of the pistons. That’s 40 per second. Kinda drafty.
Nope...it's twice per rev.
Nope. Once per rev. Watch carefully.
https://www.youtube.com/watch?v=OGj8OneMjek
I see 2 air compression events under the pistons per revolution of the crankshaft. The first 180 degree crankshaft rotation has an air compression event from both #1 and #4 pistons moving down at the same time. The next 180 degree crankshaft rotation has an air compression event from both #2 and #3 pistons moving down at the same time. So there are 1200 air compression events in the crankcase per minute in an engine at 600 RPM.
Originally Posted By: tmorris1
Put your oil in the microwave to warm it up if you are worried.
MW's heat by the excitation of water molecules. Unless your oil has a significant amount of water in it, (and I hope it does not!) the MW won't do much good.
Put your oil in the microwave to warm it up if you are worried.
MW's heat by the excitation of water molecules. Unless your oil has a significant amount of water in it, (and I hope it does not!) the MW won't do much good.
Yeah some engines will spit back the oil if they're running.
The bigger issue is that you don't know if you added to much.
Cold oil is not a problem for a warm or hot engine!
I check all engines cold in the AM, etc, so I'll know if additions are needed.
On super long trips I'll stop for lunch, etc and check the oil and add if needed
when is clear it's down for sure.
The bigger issue is that you don't know if you added to much.
Cold oil is not a problem for a warm or hot engine!
I check all engines cold in the AM, etc, so I'll know if additions are needed.
On super long trips I'll stop for lunch, etc and check the oil and add if needed
when is clear it's down for sure.
Originally Posted By: tmorris1
Originally Posted By: Vdubuk
Just out of interest,Any views on doing this guys..i dont mean from a health and safety perspective but from a mechanical point of view..is adding cold oil from top down detrimental
Put your oil in the microwave to warm it up if you are worried.
I did do one oil change in the dead of winter with a pretty warm engine and pouring in -20C good flowing synthetic. There was a few ticks and then a seriously loud CRACK! Something in the top end of my old Neon didn't enjoy sudden thermal contraction but I ran it for a couple years after without a problem.
I won't do that again with my current cars though.
Originally Posted By: Vdubuk
Just out of interest,Any views on doing this guys..i dont mean from a health and safety perspective but from a mechanical point of view..is adding cold oil from top down detrimental
Put your oil in the microwave to warm it up if you are worried.
I did do one oil change in the dead of winter with a pretty warm engine and pouring in -20C good flowing synthetic. There was a few ticks and then a seriously loud CRACK! Something in the top end of my old Neon didn't enjoy sudden thermal contraction but I ran it for a couple years after without a problem.
Patman
Staff member
The question I have is why would there ever be a need to do this? I can't see any problems with adding oil to an engine that is shut off, but it could be very messy adding it while it's running.
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