Can excess oil in the engine (3/4 Quarts) cas any damage or cause for concern? If so how do I go about fixing this. I did my first oil change and ended up emptying the 5 quart Mobil 1 can. Then I read the manual and it said the capacity is 4 1/4 Quarts. My dipstick is funny and doesnot give me accurate reading. some times I see oil all the way up to half length and sometimes slightly above the H.
Please advise.
Thx,
S

 

This is very bad. You have to take out the oil right away. It can cause leaks and go to the spark plugs.

 

Drain out the excess... 3/4 quarts over is enough to put excessive pressure on the internal seals/gaskets...

The correct way to check the oil level:
Park on a flat surface, wait 1/2 hour for all the oil to drain back into the pan. Pull dipstick, wipe clean with a lint-free rag, reinsert dipstick all the way and remove it. Now see the oil marking on the dipstick.

The key is to wait for the oil to settle back to the bottom of the pan - o/wise you will see the oil all over the dipstick and cannot get a good reading.

 

Thanks for your help. I just drained some oil out But I did drive my car around 200 miles. How can I check if I did any damage to the seals/gaskets? What other damage could I have done? I feel like such a dummy!!

 

i don't see how it can hurt. i always put 5 full quarts in my Max, and i've never put the exact amount it calls for in all the cars i have owned and never had engine problems.

 

Comments removed.

 

Please explain in technical terms how more oil in the pan will lead to "more pressure" inside the engine?????? How does more oil make the oil pump push more pressure?????????

If anything, a very big increase in the oil level might LOWER the oil pressure. But I'll refrain from the explaination until I get your reply.

 

I'll state right up front that I my comments are from my own understanding... I can't say that I can explain technically what I stated. If what I stated is incorrect, thanks for pointing it out. I thought that more oil in the pan means more oil in the crank case - which means more pressure... but apparently that is not the case.

I'm not being patronizing when I say this - please do inform us of what exactly happens if you overfill.

Apologies for any misleading anyone.

 

Live and learn. If you're not sure of something, don't give out info. The only thing I can think of that could possibly mess with oil pressure is that stupid, thick oil treatment. It makes the oil too thick to get pumped through the pump properly and will cause it to make noise.

 

Overfilling oil will not increase oil pressure. Over filling your oil will damage you cat and possibly your engine. What happens when you over fill your oil is excessive oil will get into the combustion chamber by blowbyand it will get sucked through your pcv(positive crankcase ventilation) system wich puts more HC's(hydrocarbons)into your motor that will come out your exhaust wich will cause your cat to work overtime and "burn out" and at the same time your o2 sensors will have a rich reading wich will cause your motor to run lean. Another reason ive heard of overfilling oil to cause a problem is if the oil level in your oil pan is too high then the counter weights on the crankshaft will churn up the oil and airateit so you will be pumping bubbles and not oil through your oil galleys.. And i woiuldnt worry about the 200 mi like that just dont do it again. I hope this all makes sense to ya(im not the best writer)

 

I'm confused. How would this happen?

*DING*

 

wich part are you confused with the first or second part?

 

1st..... excessive blowby via too much oil? Doesn't make any sense.

 

Well i guess saying blowby is incorrect(blowby is cylinder pressure leaking out past the rings into the crank case) What i meant is that you would have more oil slung up towards the piston so more oil will get passed the rings and into the cylinder. Even though i think the main way oil will back up into the combustion chamber is through the pcv system. Which in that case the valve covers fill up with oil and are sucked into the motor via manifold vaccuum. Does that make more sense?

 

Exactly how would more oil get slung anywhere? The oil pickup is near the bottom of the pan. How would the pick up get more oil or how would the pump be pumping more oil and/or pressure just because there was more oil in the pan?

 

Well oil doesnt just travel around the motor via the pickup and oil pump there are also baffles and such that sling oil around the bottom end of the motor. Wich makes an argument about what i said about the valve covers filling up with oil. You would think that the oil wouldnt drain back down to the oil pan as fast if you had more oil in the top of the head but then again you should be pumping the same amount of oil into the head regardless of the oil level. Although i have witnessed oil getting sucked back throgh the pcv because of oil overfilling(more times on fords than anything else).Wich i dont know How it gets there but it does.I just stumpted myself. Good point

 

As far as I know, the oil pump is the ONLY method the engine has to deliver oil to the heads. If there was so much oil that the crank foams it up, you have other problems. Now the the oil pan is a good 6-10" from the bottom of the piston. That's alot of travel for oil to sling up enough to get past 1 oil ring and 2 piston rings and get into the combustion chamber. Plus some Nissan FEATURE oil squirters that actually spray the bottom of the piston. Why don't they have these excessive oil problems?

 

Thats what I'm here for...

 

The oil pump is the only way to get to the heads but bottom end is designed to sling oil on itself. You also made a good point on the oil squirters but i think they are more aimed at the middle of the piston and when oil is slung up it can hit more of the cylinder wall, then getting above the rings. The reason the squirters dont get effected when over filling the oil is like you said before more oil wont increase pressure or pump volume so they would not be effected by too much oil. Like i said i think the bigger concern is oil getting into the pcv system rather than past the rings. Out of curiosity are you a nissan tech by anychance?

 

Maybe you can get alot of oil vapor though the pcv valve. If the valve stem seals allow blow by up though the head. That will pressurize the valve cover area and push vapor though the pcv and into the intake system.

I'm not a Nissan tech. I think of myself as SMARTER than most of those idiots!

 

That makes sense to me. And i hear ya on some of those dealer techs alot of them just suck. Are you a tech at all?

 

No but I've considered getting my ASE certs and changing careers.

 

Thats cool i have my assoc in auto technology and ive been in the field for about 2 years now and i must say that it can be a real ***** of a job sometimes but i enjoy it. Although after workin on cars for 50hrs a week you dont have as much strive to work on your own car anymore.

 

I think I get the picture...The oil level now is just below the H mark now...Thanks for all your help....Feels great to do stuff like this on my own. I think I just saved myself $35. Pepboys charges $75 for an oil change with Synthetic oil. I paid: 17.xx for Mobil 1 Synt. Got the filter and drain plug and washer from the Nissan dealer for about 10 bucks and Tada...

Thanks,
S