veteran car guy asks newbie question.

[jps4jeep]

1077451

Over Vacation my cousin and I were having a 6 pack shoot out (when you do nothing for a couple of hours but drink beer and compare knowledge of cars) and we got into this argument as to when and how to properly check oil. Both of us have built engines and do all our own maintance but this was something we can't agree on.

I ask for the knowledge of the board!

I say check 10 minutes after driving, pull out dip stick, use a paper towel (not cotton rag) clean reinsert, check again.

Cousin says check right before you turn the motor on (cold engine) doesn't matter what rag you use, clean and check again.

Who is right (pptsss I am)

Thanks
Johnny[addsig]

 

[jay89]

1077457

Sorry but the correct way to check the oil is when the car had been off for awhile. 10 minutes is too soon for all the oil to drain back down into the drain pan. If you check it right after it has been running, there is still oil up throughout the engine. You won't get a correct reading. The reading will always be a little lower. Thats a problem because then people put il in and over fill it! :-O [addsig]

 

[L33TJ33P]

1077464

Hot Oil is going to drain much faster than what you are pouring into the motor. I say 10-15 min is sufficient. That is what I have always known. And the only rags we had were our T-Shirts so it was cotton all the time ;-) [addsig]

 

[JeredYJ]

1077466

Actually, the automotive section in the Orlando Sentinel had a short article on this subject. They failed to mention what to wipe the dipstick with, but did explain when to check the oil. There are actually two answers: In older cars it was necessary for the engine to be cool to check the oil and the readings on the stick would only then be accurate. Most modern cars (90's and up) have sticks calibrated to measure the oil while the engine is hot, but it has to be off for about 4-5 min to let the oil settle. This is due to the increasing number of impatient drives who just jump out to check the oil at a gas station or some other stop, but does make it a lot more convenient.
-Jered[addsig]

 

[Deerhunter30]

1077467

I am not sure what material to use (cotton or paper towel) and cannot imagine why it would matter. I personally believe that if it takes more than ten minutes for most of the oil to drain back intot the pan, there is a problem. I ususally check within a minute or two after turning off the engine. I understand that some of the oil (usually less than half a quart) may still be up in the block, but I do not add oil until it is a quart low. If it is a half quart low I think it's OK. Also if I add oil and it ends up a quarter quart high I don't think that's a problem. Now if you are one of these types that will add a quarter quart of oil to a vehicle then wait your twenty minutes or whatever you think is sufficient to drain all the oil into the pan.[addsig]

 

[jps4jeep]

1077471

I was always told not to use cotton cause small fibers (lint I guess) could possible be left behind on the dip stick and go back into the engine. Just what I was always was told.

Isn't it funny how something so simple could be so complicated.

Johnny[addsig]

 

[graewulf]

1077472

actually, both answers are correct.. any oil that will be left in the system after more than a minute wont affect the reading enough to matter... and as for what to wipe the stick with - who cares - so long as none of the material ends up going back in with the stick.... its more important to make sure the engine is level than if its cold or warm - if you overfill by 1/2 quart it will not matter either.[addsig]