Tymo23

I changed my oil today (88' Civic sedan LX) and accidentally added too much oil, I've since then drained it and corrected the level. I didn't drive anywhere when it had too much but my car will turn itself off, shakes fairly hard and it has an obvious loss of power. What should I be looking at as a possible problem area right now or will everything go back to normal after I put some miles on the car because I haven't driven it anywhere but around the block. Thanks to anybody that can help me because I'm obviously new to this.

MindBomber

Having to much oil for that short of a period shouldn't have caused any issues..

Tymo23

Ok but when should I expect my car to start behaving like it used to?

MindBomber

The engine feeling a bit different after an oil change is normal, but there shouldn't be a any drastic changes. How much did you overfill the oil by?

Tymo23

about 2 quarts but I didn't drive it while it was over filled but it was idling for a little bit and the engine has a drastically different feel right now.

MindBomber

I expected you put 0.5-1 quart to much oil in, which isn't uncommon and not much of a concern as long as you didn't run it to long, 2 quarts is severely overfilled and may have caused permanent and severe damage to your engine depending on how long it idled for.

When the oil is that high the crankshaft repeatedly contacts the surface of the oil as it rotates and causes the oil to foam up, in turn the oil pump isn't able to pump the oil properly and the foamy oil it does pump will not do it's job. In the top end of the engine the hydrualic lifters will have problems, because you've turned non-compressable oil into a compressiable foam, and in the cylinders the oil slick thats supposed to be in the cylinders just won't be there. The increased oil pressure has the potential to blow out the valve seals and the crankcase seals, which are designed to contain oil vapour are being covered in liquid oil and may begin leaking.

I'm sorry, but you made a big mistake overfilling it by that much.

gearbox

iTrader: (95)

did he actually idle it tho? sounds like he just overfilled it and then drained some out before starting the engine.

Brenden

iTrader: (1)

If you let it run or drove it you might have caused some damage to old seals in the engine.. I wouldn't worry it can't be worse than letting the engine run short on oil...

I overfilled my 97 Honda D16y7 by about 1/2 quart to 2/3 qt, and just let it run, never changed anything, but I do have a rear main leak already so it probably took one more for the team on that ^^

MindBomber

It sounds like he idled it, but didn't drive with the engine overfilled. Draining a bit of oil out probably left the frothy oil in the pan, unless he drained it completely, so when he went to drive the engine was still suffering the effects..

Kennykid2002

iTrader: (1)

I agree with what mindbomber said, but honestly, I dont think you could have idled it long enough to cause that severe of a problem.

Unless you probably idled it for more than an hour

My other guess would be that you have bad rings, and that the overfill of oil has actually reached inside the spark plugs.
I would take em out to see if they're covered in oil, just in case

Tymo23

Thanks for all help, I ended up draining the oil again and measuring the oil very carefully like I should have the first time, then using a bit of seafoam in a few different places and everything seems as of now back to the way it used to run. No loss of power or extremely rough idle, so I'm going to say my 10 min idle with too much oil didn't kill it but gave it a good punch in the gut.

MindBomber

Good to hear it worked out.

Giving the engine a break and draining out all the oil was probably just what it needed to eliminate all the air bubbles and get it back to running well.