Why was oil level high?

Question

Civic vti em1

I was checking my oil level and it kept showing below minimum, empty or just at minimum. At one point I added a quarter of a litre and the oil level when a a third above the minimum mark. However I remember checking the next day and it was slightly above the maximum mark.

Having read some questions and answers it seems to me in the initial cases (when it showed empty or just below minimum) it may have been because the engine was running or because I checked it too soon after stopped running.

1. I take it one should not check it when running or too soon after running and if it shows empty or below minimum in these cases, one should not worry?

I have since been ensuring to check after its stopped runnning and waiting a few minutes and on each occasion it shows a bit above the minimum mark.

However I'm still wondering why on one occasion it showed just above the maximum mark.

2. What would have caused it to show just above the maximum mark and why has it now gone to showing in between the min and max? Is it the case that when I originally put oil in (I read it incorrectly), added too much oil, and then the excess oil gets burned off until it goes in between the min and max?

I need to understand why it was showing so high and why that has now gone to in between min and max.

Answer 1

I take it one should not check it when running or too soon after running and if it shows empty or below minimum in these cases, one should not worry?

As far as engine oil goes, there are very few cars which you should check the engine oil while running.

To check the oil, do the following:

• Park the vehicle on a level surface.
• Shut off the engine and wait a few minutes for the oil to drain back down into the sump. NOTE: In most cases you can check the engine oil level when the engine is cold. Check your owner's manual as to whether this can be done with your Civic.
• Pull the dipstick and wipe it off with a clean rag.
• Re-stick the dipstick and pull it out to read the measure.

When adjusting the oil height, you should try to keep it as full as possible, up to the full mark. Between the lines is just fine, but full will ensure your engine has all the oil it needs to function properly. Overfull is not good, but if it's only slightly over it shouldn't hurt anything (NOTE: Slightly means something like a mm over ... if much more than that, you need to drain or have drained the excess. Too much oil can cause other issues.)

What would have caused it to show just above the maximum mark and why has it now gone to showing in between the min and max? Is it the case that when I originally put oil in (I read it incorrectly), added too much oil, and then the excess oil gets burned off until it goes in between the min and max?

It really depends on how you've been checking your oil. If you've not been on a level surface, it may have shown too much. If you've only ever checked it while it's been running, it has probably shown low (every time). If the one time it showed over full you'd actually waited (for whatever reason), it may have actually been reading correctly. That is your call to figure out why, as all I can do is second guess you.

In newer cars with a properly running engine, the engine will not "burn off" too much oil. If the oil level is too high, you can cause a situation where the crankshaft of the engine starts hitting the oil. This aerates the oil and actually causes a drop in oil pressure. It also causes the engine to work harder to maintain itself at any give speed.

Bottom line is, read the oil levels at the correct time and at the correct way. If there's not enough oil, add some oil to ensure you have enough. If there's too much, remove the excess so as not to cause issues. Your car will thank you for it.

Answer 2

To read the oil level: (general method: use the manufacturers method if available)

1) stop engine & wait 10 minutes.

2) remove dipstick, wipe clean and refit.

3) remove dipstick and then read level.

4) adjust oil level appropriately - the “usual” volume between min and max mark is 1 litre.

Some find that a trace of white paint on the edge of the dipstick makes it easier to read - not done that myself though.

Difficult to be sure of your various historical readings, so do it correctly and go from there.