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Added too much oil - did I ruin my engine?

I recently changed the oil in my 1998 Honda CRV and overfilled it. I don’t know exactly how much volume, but it was perhaps 1/4inch above the full line on the dipstick. To make matters worse, I then made a two-thousand mile round trip from southern California to New Mexico and back. I know, dumb.

Some things I’ve noticed, which I fear resulted from my mistake:

  1. I have an oil leak, I believe at the cylinder head cover gasket on one side, near the distributor cap.
  2. The oil level is now between the two dots on the dipstick.
  3. While driving down the freeway at 70mph, I thought I saw the temp rise a little and then drop back to mid, a couple of times.

What I really want to know is if I have caused any permanent/serious damage to the engine? I read some terrifying accounts online about people blowing head gaskets and mixing coolant and oil or getting engine oil into the transmission. Some people even reported bending crankshafts! Fouling spark plugs etc etc.

One last thing, the car runs smoothly, perhaps not as powerful as I would like, but gets approx. 25mpg - which is good for this model/year.

Any help/suggestions as to how I can determine exactly what has happened and what I should do next would be greatly appreciated.

Relax man.

  1. Have a trusted local independent mechanic check this out. Why do you think you have a leak?

  2. That is just fine. You want it somewhere between the dots. It need not be exactly in the middle.

  3. Totally normal. The thermostat is opening and closing to keep the engine temperature at optimal. temperature.

-A quarter inch above full is not a big deal. You’d have to overfill the car a lot more than that to do damage. There are some people that purposely slightly overfill their cars to add oil volume.

-Your oil consumption on a 2,000-mile trip may be totally normal. What signs are you seeing of a leak? Is there oil on the outside of the engine or the ground?

-The temp gauge rise/fall may or may not be normal. (Can you say for sure that it has not always done this and you’re just now noticing?) If your car has never done this before, it is likely not normal. This behavior might be expected on a hot day while idling, but should not happen on a highway trip. You may have a sticking thermostat or a worse problem. I’d get this one checked out. It is not likely related in any way to overfilling the oil.

ur motor uses 5 qts? approx? how many quart bottles did you add? why did you add more than required? were you distracted? or just guessing?

It’s A 1998 Honda, Built Between Mid 1997 And Mid 1998 Which Makes It 14 Or 15 Years Old, A Senior Citizen In “Car Years,” To Be Sure.

Senior citizens have little aches, pains, and idiosyncrasies that seem to accumulate as part of the aging process. Some of these aren’t worth fixing with the limited time left on the old clock, but often symptoms can be relieved a bit at reasonable cost and effort.

As the other comments suggest, take your car and concerns to a competent mechanic and have him/her sort things out. Develop a list of recommended maintenance and repairs and help with prioritizing it.

Somewhere down the line you’ll have to start a “letting go” process and begin thinking about a younger, fit, and more able replacement for your old friend.

CSA

The overfill probably didn’t hurt anything. A gross overfill can cause the oil to get whipped into a foam, which of course doesn’t lubricate well or pump around well, but I don’t think you were that high.

As others have stated or implied, if the level on the dipstick was just 1/4 of an inch above the “full” mark, nothing was harmed.

As to the other situations that the OP noted, when a vehicle is this old, all sorts of leaks and other problems will occur. Regarding the leak, this may well have been present, prior to the slight overfill of oil. The OP may have started looking more closely for problems once he realized his goof with the oil, and may have noticed for the first time that this problem–of possible long duration–was present.

The drop in oil level on the dipstick is almost surely due to some oil consumption, which is to be expected on an engine that is this old.

As to the location of the oil leak, I am assuming that the OP is referring to the valve cover gasket, rather than the head gasket, but if there is any possibility that the head gasket is leaking, then it is imperative to get the vehicle to a competent mechanic a.s.a.p. And, since there may be an issue with temporary temperature spikes in the cooling system, that is another reason to get thee to a mechanic very soon.

I don’t think he mentioned “spike”. It running up and coming back down is likely just the thermostat being closed and opening. If you see it ramping up quick to red point and then coming down, that’s when you have to worry.

But you’re right. Making sure there isn’t an issue with the HG is always a good thing.

Still runs, right? If you drove it home; No problems.

I’d be shocked if it DIDN’T leak a bit and use a bit of oil. You can but 1/2 quart over in most cars with no issues, especially a 5 qt oilpan.

Thanks everyone - I was pleasantly surprised by the number of helpful comments/questions posted in response!

To update and clarify my situation…

  1. My car runs great - age considering and all.

  2. According to a diagram I found in the service manual, I would say there is an oil leak around the cylinder head plug (a black plastic plug on the side nearest the distributor where the valve cover meets the rest of the motor). There was some oil at this joint and dripped below.

  3. I was concerned with the oil being between the dots because I am certain it was 1/4inch above the top dot a week earlier - before the road trip. I was surprised because I have never burned off this much oil in a week before and assumed I must have caused a big leak someplace.

  4. On second thought, I don’t think there is any issue with the temp, just my hyper-vigilance and probably the thermostat opening and closing as suggested by JosephEMeehan.

In any case, I am quite relieved by the comments you have all posted, and gladly accept any further suggestions. Do I need to get the cylinder head plug replaced or just keep an eye on the oil levels?