What happens to the engine oil when the Oil cap and/or dipstick is opened?

D.V.R · 10th November 2009, 15:50

As the title of my thread goes I would like to know what would the effect be when th engine is running at idle and the engine oil cap is opened or the dipstick is removed?

MODS:-Edit the title as required or merge with any other similar thread if existing?

Gansan · 10th November 2009, 15:55

Well, I don't think anything will happen. It may splash out if the engine is revved, I suppose.

D.V.R · 10th November 2009, 15:57

@Gansan-Do you mean to say that if the engine is at idle there will be no splashing of engine oil and only if its revved the oil pops or splashes out?

Gansan · 10th November 2009, 15:59

Yes, I think so, though I have not tested it out.

shishir_bn · 10th November 2009, 16:02

guys, IMO the oil will be running inside the engine and it splashes out

D.V.R · 10th November 2009, 16:03

Ok no worries,so does it mean that if an engine squirts out oil only when revved is a healthy one and if it doesnt squirt out oil its an unhealthy one?Please correct me if I am wrong.

Gansan · 10th November 2009, 16:10

Well, I am treading on thin ice here, especially about the healthy/unhealthy part! I think when the oil cap is removed, even with the engine off, the cap/neck should be clean with no signs of splash. Even if it splashes, it may just be a case of excess oil in the sump.

If you specify the exact nature of your problem, I am sure the gurus here will respond immediately.

r@CYR@y · 10th November 2009, 16:10

Theoretically many things will happen when idling if the car is in perfect running condition, But in reality nothing is perfect (

).
As soon as you start the engine the oil starts to gradually warm up its working temperature, Now since the oil is getting hotter every rev, the air in the oil container becomes hot and starts exerting pressure on the cap, If you open the cap suddenly at this time the cap will fly with high velocity and unfortunately if you are in its way It will hit you hard very hard, So its wise to not to open the cap..

DO NOT OPEN THE LID WHEN THE OIL IS HOT (Read the warning on the cap) If wish to see what is happening when the engine is idling always remember to open it partly so that the air inside escapes slowly without blowing the cap..

I say you better do not experiment with this as it may cause PHYSICAL INJURY to you or others near you.

Keep revving...

D.V.R · 10th November 2009, 16:22

No I jut wanted to know whether my engine is healthy or not thats it,I know that there is a thing called as compression test but was reading another thread where a buyer had reported doing this to know the engine condition of a second hand Indica.

siddartha · 10th November 2009, 16:49

depending on the position of the dip stick of your vehicle , you could end up getting some water entering the dipstick opening during washing and also if u have waded thru water during rains.

Shan2nu · 10th November 2009, 17:29

Get answers to all you sadistic questions here. LOL

YouTube - Honda Civic Death

Shan2nu

D.V.R · 10th November 2009, 18:11

r@CYR@y-Yes I wouldn't do it on a hot running engine for the safety of myself and others.

siddartha-The car engine is not being washed its just stationary.

Shan2nu-Man thats sacrilege.

It seems like I have not got across my point properly.I dont want to drive my car without the oil cap or dipstick.What i wanted to know was what happen if park the car after a short drive(engine is warm),stop the engine,open the bonnet remove the dipstick and engine oil cap,get in and crank.I will not be driving.What happen to the oil will it squirt out or remain inside?

bblost · 10th November 2009, 18:17

Engine oil can and does reach a high temperature.
I learnt this the hard way.

My old bike, a HH Splendour needed an oil change.
I went to the nearby store. They were out of stock. So I ended up riding close to 5 kms before getting the oil and returning home.

Right away sat down, put on my cotton gloves with rubber grips.
Long story behind the gloves. Have 8 stitches on my finger before my Dad made them mandatory.

So I opened the nut under the engine cover. HOT oil all over my hand.

Lesson learn't.

D.V.R · 10th November 2009, 18:25

@bblost-sorry to hear that mate,but dont we learn it the hard way.

I am not intrested in opening the engine oil drain valve under the engine but the engine oil filling cap on top of the engine.

ElantraGT · 10th November 2009, 18:30

Quote:

Originally Posted by D.V.R

No I jut wanted to know whether my engine is healthy or not thats it,

DVR, Splashing of engine doesnot specify if the engine is healthy or not.

In most cars, oil is sucked out of the oil pan by the oil pump, run through the oil filter to remove any grit, and then squirted under high pressure onto bearings and the cylinder walls. The oil then trickles down into the sump, where it is collected again and the cycle repeats. So the chances of the oil splashing can occur even if the engine is under idling situation.

As most of the members have advised please do not open the Oil cap when the engine is running / Hot.

10th November 2009, 15:50	#1
D.V.R BHPian Join Date: Jul 2006 Location: Sydney / Secunderabad Posts: 278 Thanked: 14 Times	What happens to the engine oil when the Oil cap and/or dipstick is opened? As the title of my thread goes I would like to know what would the effect be when th engine is running at idle and the engine oil cap is opened or the dipstick is removed? MODS:-Edit the title as required or merge with any other similar thread if existing?
	() Thanks

10th November 2009, 15:55	#2
Gansan Senior - BHPian Join Date: May 2009 Location: Chennai Posts: 4,535 Thanked: 5,561 Times	Well, I don't think anything will happen. It may splash out if the engine is revved, I suppose.
	() Thanks

10th November 2009, 15:57	#3
D.V.R BHPian Join Date: Jul 2006 Location: Sydney / Secunderabad Posts: 278 Thanked: 14 Times	@Gansan-Do you mean to say that if the engine is at idle there will be no splashing of engine oil and only if its revved the oil pops or splashes out?
	() Thanks

10th November 2009, 15:59	#4
Gansan Senior - BHPian Join Date: May 2009 Location: Chennai Posts: 4,535 Thanked: 5,561 Times	Yes, I think so, though I have not tested it out.
	() Thanks

10th November 2009, 16:02	#5
shishir_bn Senior - BHPian Join Date: Nov 2009 Location: Bangalore Posts: 1,195 Thanked: 120 Times	guys, IMO the oil will be running inside the engine and it splashes out
	() Thanks

10th November 2009, 16:03	#6
D.V.R BHPian Join Date: Jul 2006 Location: Sydney / Secunderabad Posts: 278 Thanked: 14 Times	Ok no worries,so does it mean that if an engine squirts out oil only when revved is a healthy one and if it doesnt squirt out oil its an unhealthy one?Please correct me if I am wrong.
	() Thanks

10th November 2009, 16:10	#7
Gansan Senior - BHPian Join Date: May 2009 Location: Chennai Posts: 4,535 Thanked: 5,561 Times	Well, I am treading on thin ice here, especially about the healthy/unhealthy part! I think when the oil cap is removed, even with the engine off, the cap/neck should be clean with no signs of splash. Even if it splashes, it may just be a case of excess oil in the sump. If you specify the exact nature of your problem, I am sure the gurus here will respond immediately. Last edited by Gansan : 10th November 2009 at 16:15.
	() Thanks

10th November 2009, 16:10	#8
r@CYR@y BHPian Join Date: Oct 2009 Location: Pride of Deccan - Hyderabad Posts: 78 Thanked: Once	Theoretically many things will happen when idling if the car is in perfect running condition, But in reality nothing is perfect ( ). As soon as you start the engine the oil starts to gradually warm up its working temperature, Now since the oil is getting hotter every rev, the air in the oil container becomes hot and starts exerting pressure on the cap, If you open the cap suddenly at this time the cap will fly with high velocity and unfortunately if you are in its way It will hit you hard very hard, So its wise to not to open the cap.. DO NOT OPEN THE LID WHEN THE OIL IS HOT (Read the warning on the cap) If wish to see what is happening when the engine is idling always remember to open it partly so that the air inside escapes slowly without blowing the cap.. I say you better do not experiment with this as it may cause PHYSICAL INJURY to you or others near you. Keep revving...
	() Thanks

10th November 2009, 16:22	#9
D.V.R BHPian Join Date: Jul 2006 Location: Sydney / Secunderabad Posts: 278 Thanked: 14 Times	No I jut wanted to know whether my engine is healthy or not thats it,I know that there is a thing called as compression test but was reading another thread where a buyer had reported doing this to know the engine condition of a second hand Indica.
	() Thanks

10th November 2009, 16:49	#10
siddartha BHPian Join Date: Aug 2008 Location: bangalore Posts: 671 Thanked: 24 Times	depending on the position of the dip stick of your vehicle , you could end up getting some water entering the dipstick opening during washing and also if u have waded thru water during rains.
	() Thanks

10th November 2009, 18:11	#12
D.V.R BHPian Join Date: Jul 2006 Location: Sydney / Secunderabad Posts: 278 Thanked: 14 Times	r@CYR@y-Yes I wouldn't do it on a hot running engine for the safety of myself and others. siddartha-The car engine is not being washed its just stationary. Shan2nu-Man thats sacrilege. It seems like I have not got across my point properly.I dont want to drive my car without the oil cap or dipstick.What i wanted to know was what happen if park the car after a short drive(engine is warm),stop the engine,open the bonnet remove the dipstick and engine oil cap,get in and crank.I will not be driving.What happen to the oil will it squirt out or remain inside?
	() Thanks

10th November 2009, 18:17	#13
bblost Team-BHP Support Join Date: Jul 2007 Location: Hyderabad Posts: 11,008 Thanked: 15,366 Times View My Garage	Engine oil can and does reach a high temperature. I learnt this the hard way. My old bike, a HH Splendour needed an oil change. I went to the nearby store. They were out of stock. So I ended up riding close to 5 kms before getting the oil and returning home. Right away sat down, put on my cotton gloves with rubber grips. Long story behind the gloves. Have 8 stitches on my finger before my Dad made them mandatory. So I opened the nut under the engine cover. HOT oil all over my hand. Lesson learn't.
	() Thanks

10th November 2009, 18:25	#14
D.V.R BHPian Join Date: Jul 2006 Location: Sydney / Secunderabad Posts: 278 Thanked: 14 Times	@bblost-sorry to hear that mate,but dont we learn it the hard way. I am not intrested in opening the engine oil drain valve under the engine but the engine oil filling cap on top of the engine.
	() Thanks