Author Topic: Too much oil (Read 4148 times)

skypoint · « **on:** June 14, 2005, 08:13:56 pm »

What is the downside of too much oil in the engine? I tried to do some research and what I foun was that the engine will burn oil and therefore run less cleanly.

Would there be any harm done to the engine as a result of too much oil?

tpl · « **Reply #1 on:** June 14, 2005, 09:18:22 pm »

depends how much too much.

If the engine is so far over that the crankshaft hits the oil then the sump will get full of oil foam....oil pumps pump liquid not foam.

If the oil level is above the sump gasket level then that gasket will undoubtedly leak... however, before that happens the oil foam problem will happen.

If the oil level is upto the main bearings then probably all of the above plus the front and rear seals will leak copiously.

Burning oil in those conditions is the least of your problems.

Now the good news.

A small amount over the top of the dipstick mark wont matter, say 1/4" over

If you really wish to get rid of a small amount....change the filter and install the new one without filling the new one with oil..that on most cars gets rid of around 1/2 litre.

If you are really worried then drain the oil and replace with the right amount from the manual. Oil changes are cheaper than engines

Driver · « **Reply #2 on:** June 14, 2005, 11:11:09 pm »

back in 1997 i poured half liter more than I should in my old nissan sentra and the engine stumbled everytime i step hard on the gas. idle was fine, upto 2500 rpm, beyond that i loose power

Scaerio · « **Reply #3 on:** June 15, 2005, 11:43:35 am »

I read a story in the UK mag "Practical Classics" about a guy who literally filled his 1970s Land Rover's engine up to the cap with oil. When he cranked it over, it blew up! The story showed a picture of a chunk of a piston rod, which the guy's wife sent into the mag along with the story!

(Message edited by gkjsooley on June 15, 2005)

ericthejet · « **Reply #4 on:** June 15, 2005, 05:40:15 pm »

Do NOT ever overfill the crankcase with oil. Get out of the habit of thinking even a little bit is ok. As far as the dipstick is concerned make sure you check the mark when the oil is hot and the engine has been off for about 60 seconds, level ground.

mrthompson · « **Reply #5 on:** June 15, 2005, 05:47:23 pm »

I thought you are supposed to check engine oil when the engine is cold? That way ALL the oil is in the oil pan and you get a more accurate reading.

21Rouge · « **Reply #6 on:** June 15, 2005, 06:01:42 pm »

My car does not show the final oil level by the dipstick for at least an hour after having been driven. If shows full when 'cold' then that all is fine.

skypoint · « **Reply #7 on:** June 15, 2005, 07:07:56 pm »

I'm concerned because my car's dipstick has been showing about half an inch above the full mark once the engine has been off for about 2 minutes after a long drive. I haven't noticed any kind of negative performance, however.

tpl · « **Reply #8 on:** June 15, 2005, 09:19:20 pm »

Some cars like it hot, some like it cold.

BMWs for instance is hot + 5-10 minutes

Skypoint, have you checked it cold?

barrie1 · « **Reply #9 on:** June 15, 2005, 09:59:05 pm »

Check your oil when your engine is cold as oil expands when it is hot. You can get false readings when the oil is at hi-heat temps. If you have at least as much as the dipstick requires without being too far up the stick you will be alright.

Sterling · « **Reply #10 on:** June 15, 2005, 11:13:03 pm »

I thought the dipstick would read low when hot because some oil hadn't drained back to the sump. By the time the oil has cooled, it has all drained back resulting in an accurate reading.

articsteve · « **Reply #11 on:** June 15, 2005, 11:46:07 pm »

I'm concerned because my car's dipstick has been showing about half an inch above the full mark once the engine has been off for about 2 minutes after a long drive. I haven't noticed any kind of negative performance, however.

That is not good. You won't notice any adverse effects, but unnecessary pressure is building in your motor. It causes premature leaks eventually and turbos complicate oil leaks.

What is the level in the morning? Must be another 1/2 inch?

The valve train holds lots of oil depending on the motor. The old GM 6.2s held a full 1 litre in the heads soon after turned off. This caused lots of problems in false readings.

barrie1 · « **Reply #12 on:** June 15, 2005, 11:48:02 pm »

Yes you are right Sterling as thats why we should wait until the oil is cool to get the proper reading. It does take a few minutes to drain back down and with the heat expansion you still don't get a good reading until the engine is cold.

ericthejet · « **Reply #13 on:** June 16, 2005, 07:05:33 pm »

Even if oil expanded at a rate of 1% a sump that holds 4L of oil would show an extra 4mm of oil? I don't think oil expands in volume enough to measure with a dipstick IMO.

If your car is up to temp and it takes more than 1 minute for it to reach the sump I think your oil may be a bit thick. 5w-30 at operating temp flows like water and will drain to the sump in a few seconds will it not?

Oil does not need to cool(hours later BTW) before you get a proper reading.

If your oil is beyond the "full" mark then it's too full, plain and simple.
Molehills into mountains perhaps? :-)

barrie1 · « **Reply #14 on:** June 16, 2005, 10:20:27 pm »

I believe you may be correct.

Sterling · « **Reply #15 on:** June 17, 2005, 12:03:46 am »

I think a few seconds may be a little quick. When you open the drain plug to change hot engine oil there is still oil drizzling out for much longer than a few seconds.

articsteve · « **Reply #16 on:** June 17, 2005, 10:27:40 am »

When you open the drain plug to change hot engine oil there is still oil drizzling out for much longer than a few seconds.

Depending on the motor it will drip for at least an hour.

That is why with quick lubes people will never get a perfect oil reading unless the dude who is filling it is really good and knows exactly how much to hold back on certain models.

weebl · « **Reply #17 on:** June 17, 2005, 10:52:22 am »

That is why with quick lubes people will never get a perfect oil reading unless the dude who is filling it is really good and knows exactly how much to hold back on certain models.

And you have to ask yourself, just how many people working in a quick lube are really good? Not just for the fill level, but any aspect of the servicing.

I've seen these things happen (I used to go to quick lubes until it got too scary):

- after "checking" an air filter, installing it backwards
- recommending wrong viscosity
- adjusting tire pressure on hot tires
- trying to push with hands on hood to close it (leaves nasty dents! - the guy looked at me like I had 3 heads when I stopped him as he was about to do it)
- refilling washer fluid tank with plain water

I'd much rather do oil changes myself (and always have), but unfortunately the complex where I live doesn't permit that. So from now on for me it's either the special at the dealership, or going to my regular independent mechanic.

ericthejet · « **Reply #18 on:** June 17, 2005, 11:57:01 am »

This is just too fun somedays. :-)

articsteve · « **Reply #19 on:** June 17, 2005, 12:08:47 pm »

This is just too fun somedays

Eric, leave the condescending stuff to experts like me.

I happen to think Weebls' last post was right on as I have experienced the exact same things in my past. Naturally, I think all the content in my posts are "spot on" as well.

If your car is up to temp and it takes more than 1 minute for it to reach the sump I think your oil may be a bit thick. 5w-30 at operating temp flows like water and will drain to the sump in a few seconds will it not?

After reading your above statement I would say that you have never personally changed the oil in a car.