[gigy]

I don't agree with checking oil when engine is cold. ITs not going to give actual level.
You have to run it for few minutes, then let it stop and stay for few minutes and then check.
The procedure for oil change also says so, as per baleno manual.
Fill oil till top marking on dip stick, run the engine for 3 minutes and then shut it for 3 minutes and check the level to be at the full mark. topup to bring it to that level if necessary.
I normally refill to 80% after oil change.

[Ravveendrra]

Originally Posted by gigy

I don't agree with checking oil when engine is cold. ITs not going to give actual level.
You have to run it for few minutes, then let it stop and stay for few minutes and then check.
The procedure for oil change also says so, as per baleno manual.
Fill oil till top marking on dip stick, run the engine for 3 minutes and then shut it for 3 minutes and check the level to be at the full mark. topup to bring it to that level if necessary.
I normally refill to 80% after oil change.

If that is what your manual directs, then that is what you should do. However, most manuals specify that oil level is to be checked when the engine is cold or some time after the engine has stopped running. This is because oil that is in the upper reaches of the engine trickles down slowly. Of course it depends on how the dip-stick is caliberated - if there is a margin above the max mark on the dip stick, in other words if the dip stick is caliberated taking into account the oil outside the sump, then it will not matter if the mark goes above the max mark for a little while when the engine is switched off. However, if there is no leeway above the max-mark on the dip stick and the dip-stick is caliberated without leaving any room for oil that may be outside the sump (and which may return to the sump in some time) it is best to check the oil level when cold. In all cases, it is best to follow the manufactureres instructions. Overfilling oil can be as dangerous to the engine as running it with less/no oil.

Cheers,

[bosporus]

Myth-busting: What the manufacturers actually say about checking engine oil

My car manual said one thing. The usually correct t-bhp community said something else. The difference between the two approaches was the difference between my engine oil level being ok, or in need of top-up. So, I asked the workshop service manager (they agreed with the manual) but they've been known to be wrong too.

Looking for a definitive answer, I scoured for manuals where I could find them, for all the major manufacturers. I checked manuals of Honda(US), Hyundai, Mahindra, Maruti, Skoda, Toyota, VW, and the following are my consolidated learnings:

1. Park car on level surface
This is pretty much intuitive and not a matter of debate. However, it's just something to be mindful of.

2. Engine SHOULD be at operating temperature (warm, NOT COLD)
Not only do the manufacturers want your engine to be warm when engine oil is checked, they actually want it to be at operating temperature. Therefore, one would assume that the best time to actually check it would be after one is back from a drive - NOT, first thing in the morning.

I mention drive versus just switching your car on for a few minutes because cars today are very good at temperature management, and just keeping your car switched on without moving will not take the engine up to running temperatures. This is the reason most manufacturers today actually advise against idling your car before driving - the recommendation is, switch on & drive, without high revs for the first few kilometres. I digress here from the main topic of engine oil, because even on t-bhp, a lot of experienced members have stated that they idle for a few minutes before they take their car out, in the morning.

Back to operating temperatures, some manufacturers (Mahindra, Hyundai, Skoda, Toyota, VW) are very clear that the engine should actually be at operating temperatures, when the oil is checked. Honda simply says, turn off the engine & wait for a few minutes before checking, so operating temperature is assumed.

Maruti, however, it seems, has decided to cause the general confusion on this matter - because it mentions "The oil level should be checked either before starting the engine or at least 5 minutes after stopping the engine.". This gives the impression that the engine can be checked cold.

However, clarification is provided in the very next section, Refilling, where, after warning of the dangers of overfilling with engine oil, they clarify "After refilling, start the engine and allow it to idle for about a minute. Stop the engine, wait about 5 minutes and check the oil level again.". In other words, for a precise measurement of engine oil, the engine should not be cold.

In other words, manufacturer consensus says, engine at operating temperature, and not a cold engine, gives accurate engine oil reading.


3. Wait after switching off the engine
All manufacturers need you to wait a few minutes after switching off the engine, so that the engine oil in circulation flows back into the engine sump.

The times specified by various manufacturers are as follows:
- 1 minute: Hyundai
- a few minutes: Honda(US), Skoda, VW
- 5 minutes: Maruti, Toyota
- 10 minutes: Mahindra

Hyundai is an outlier, but could be because the manual belongs to a Santro. Mahindra seems to be overcautious about time, because of higher engine capacity - though the Toyota Fortuner, to which the above manual references, and which has a bigger engine, thinks 5 minutes is ok. It would be fair to say you should be safe with 5-10 minutes, and in Indian weather conditions, the engine will not cool dramatically so within that time frame.

No manufacturer says 20 minutes - the consensus that seems to be on this thread.

4. Measure & top-up, if necessary (You know the drill)
If in doubt, do refer to any of the reference manual images given below.

Do weigh in with further manuals and referenced facts.

FYI: The manuals are attached in the following order: Skoda, VW, Toyota, Mahindra, Honda (US Civic), Hyundai, Maruti.

[Jaggu]

I would say refer to your owners manual, design of dipstick might vary.

I generally check when its cold, and if its below middle level I correct it. Its a general rule of thumb, and do it once every month or 2000 kms. Has served me well for last 20 years or so.

[techiecal]

I usually check the oil on a cold engine. If it has to be checked on a warm engine all you have to be careful about is to give time to let the oil flow down from the various parts of the engine to the sump. 5 minutes is sufficient most of the time. Basically it boils down to the fact that you must get the correct reading on your dipstick which will only happen when all the oil in your engine is in the sump, whether the engine is cold or warm.

[bosporus]

Originally Posted by Jaggu

I generally check when its cold, and if its below middle level I correct it. Its a general rule of thumb, and do it once every month or 2000 kms. Has served me well for last 20 years or so.

We may have old habits that may not have caused any perceptible harm, but that doesn't make them correct, and neither do they preclude future issue as a result of the wrong practise. It's this 'cold engine' bias of this thread, not supported by my car's manual, that caused caused me to investigate. My objective was simply to point out the fallacy in accepted knowledge, so that those who want to follow the correct procedure know better.

You, sir, are a moderator, and "i've been doing this for years" kind of statements, unsupported by facts, do more harm than good to the community.

[bosporus]

Originally Posted by techiecal

I usually check the oil on a cold engine. If it has to be checked on a warm engine all you have to be careful about is to give time to let the oil flow down from the various parts of the engine to the sump. 5 minutes is sufficient most of the time. Basically it boils down to the fact that you must get the correct reading on your dipstick which will only happen when all the oil in your engine is in the sump, whether the engine is cold or warm.

Heat causes oil to expand, volumetrically. Checking on a cold engine will understate the amount of oil in your engine, by a small degree or a large one, depending on the ambient temperature of your surroundings. This may cause you to add unnecessary engine oil in your car - hence the recommendation from manufacturers to check on an engine at operating temperatures. Best case, you've just wasted some money adding unnecessary amount of oil; worst case, you've overfilled it, which could lead to potential damage.

[GTO]

Originally Posted by bosporus

Not only do the manufacturers want your engine to be warm when engine oil is checked, they actually want it to be at operating temperature. Therefore, one would assume that the best time to actually check it would be after one is back from a drive - NOT, first thing in the morning.

Tom & Ray from Cartalk have an interesting discussion on this - link.

RAY: But a few years ago, Ford Motor Company started recommending that people check their oil on Fords, Lincolns and Mercuries when the engine was warm.

TOM: "Warm!" we said. "How can this be?" So we called Ford and they told us that they determined that very few idiots like us were going out first thing in the morning in their bare tootsies and checking the oil. Most people, they said, tended to check their oil when they stopped for gas, when the engine was warm. So they simply recalibrated their dipsticks to read correctly in a warm engine, when the oil has heated up and expanded.

The most important question is, what is the difference between the levels when hot or cold? Answer = ~100 ml.

RAY: He said the amount of oil at the top of the engine wouldn't be enough to make any significant difference. "Unless the oil passages are all plugged up, you're probably talking about an eighth of a quart or less," he said. Not enough to induce you to add a quart when you don't really need one.

[vnabhi]

Originally Posted by GTO

Tom & Ray from Cartalk have an interesting discussion on this - link.



The most important question is, what is the difference between the levels when hot or cold? Answer = ~100 ml.

I was always following the cold engine check method. Perhaps old-timers like me keep doing that, going by the posts on the preceding page. But thanks to this thread, I checked my Fiesta in both conditions.

When I checked on Sunday morning on a cold engine, the dipstick showed a level of 1/4th between the minimum and maximum levels. I was kind of surprised because I'd filled up Mobil Synthetic for the first time around 2500 kms back.


I checked again after driving 15 kms to work today, around 45 minutes after reaching office. It showed almost at maximum level. I was kind of releived to see this.

Given this case, I wonder if the difference is only 100 ml, as claimed by Ford.

[Jaggu]

Originally Posted by bosporus

You, sir, are a moderator, and "i've been doing this for years" kind of statements, unsupported by facts, do more harm than good to the community.

Well i stated the facts that i know off. Have you measured the difference in oil dip stick level after warming up? Is it (the variation) same and consistent with all vehicles? And more importantly how much is it (quantity)?

So please read a post and understand clearly what it means before going ballistic on someones experience.

1- I said refer to the owners manual for the right method! This logic is based on the fact that each engine design is different from the other and manufacturer knows the best and they will advice you the best.

2- I mentioned clearly what i do, which is a very simple but effective. Now the logic you want to know? Here goes....

Why while engine is cold? I don't like to burn my finger or hands to start with. And for me i just don't stop with checking oil, i do poke my hands further inside to check this and that.

Second - "as per my observation" the difference in oil level after running Vs parking has been minimal. So much so that it is difficult to even notice, esp when it is closer to full. As the level drops and anything from 3/4 to 1/2 one needs to be watching. 1/2 mark and down one needs to attend to the issue.

If you check the manual, it also says something similar. So my "common man" method is similar to what the scientific manual says.

Again going back to manual, please understand that esp the european or american manuals will look from a perspective of a mechanic with good details, since most often the owners themselves carry out oil replacement at petrol pumps or DIY, unlike in India. Hence it is bound to be best method, and most idiot proof too.

Another interesting fact usually the dip stick will have about 1/2 to 3/4 liter as range and this is good enough buffer. They are designed also with ample buffers, if an engine takes 3 liter, it can run under full stress even with say 2.5 liters.

Finally you don't have to be worried about 100-200 ml difference in oil level as long as it is in safe zone. None of us are running race engines in which such a difference can result in performance variation or engine life.

Now sue me for what i know.

EDIT: Whoops GTO has already posted most of this lol

[ckranjan]

This is what the elite i20 manual says :



I guess this is clear enough and there is no room for any doubts.

[techiecal]

Originally Posted by bosporus

Heat causes oil to expand, volumetrically. Checking on a cold engine will understate the amount of oil in your engine, by a small degree or a large one, depending on the ambient temperature of your surroundings. This may cause you to add unnecessary engine oil in your car - hence the recommendation from manufacturers to check on an engine at operating temperatures. Best case, you've just wasted some money adding unnecessary amount of oil; worst case, you've overfilled it, which could lead to potential damage.

Yes,in cold countries, but in our temperate climate you can easily verify that any difference in the dip stick levels on a cold engine and warm engine are not noticeable. Having said that, a vehicles operating temperature will be more or less the same whether it is running in a tropical country or a cold country. Hence, to factor out the ambient temperature manufacturers suggest checking at operating temperatures.

[bosporus]

Originally Posted by GTO

Tom & Ray from Cartalk have an interesting discussion on this - link.

The most important question is, what is the difference between the levels when hot or cold? Answer = ~100 ml.

That was a very interesting post. And quite right; the manufacturer consensus now seems to be to check engine oil when the car is at operating temperature.

However, apart from that, I found myself questioning what they say, and you will too, if you bear with me here please.

1. Quantified, Personal Experience

I had the same experience as vnabhi.

Originally Posted by vnabhi

I checked my Fiesta in both conditions. When I checked on Sunday morning on a cold engine, the dipstick showed a level of 1/4th between the minimum and maximum levels. I was kind of surprised because I'd filled up Mobil Synthetic for the first time around 2500 kms back.

I checked again after driving 15 kms to work today, around 45 minutes after reaching office. It showed almost at maximum level. I was kind of releived to see this.

Given this case, I wonder if the difference is only 100 ml, as claimed by Ford.

When I checked my Vento cold, the level was at the edge of the lowest point on the dipstick. Now, it had been a month since I last checked, when it was ok, so this psyched me. I opened the manual and read the 'check at normal operating temperature' recommendation. So, next day, after a drive, I waited for a few minutes & checked - this time, the dipstick level was bang in the middle. Now, the VW manual says the following:
- my cold engine level of dipstick: 1 liter engine oil MUST be filled
- my warm engine level of dipstick: 0.5 liter engine oil CAN be filled

In other words, top up was not required at my warm engine location, but that's not the point here.

The point here was that the difference between the two readings, as per VW's recommendations of the amount of oil that can be added, is not 100ml, but a good 500ml.

2. 100ml difference from cold to hot is NOT what the expert said
The expert in the blog refers to user behavior, where they stop at a pump & check engine oil, and mentions that oil could be at the top of the engine and all of it may not have come back to the sump, but inspite of that, the difference between the two readings would be 1/8th of a quart. He is not talking of a cold reading vs. a hot reading. He is talking of a hot reading with all oil back in the sump, vs. some of the oil still at the top of the engine.

So, the 1/8th of a quart (118ml, to be precise) he mentions is about how precisely you calculate the oil levels when the engine is hot.

Needless to say, a recalibration that takes into account all oil in sump (or not) is impossible. The only recalibration spoken about is simply a cold engine or a hot engine, and the leeway we have, that the expert refers to, is in how long we wait before we take a reading.

So, the blog was very interesting, until the end when they got their conclusions wrong.

Originally Posted by techiecal

Yes,in cold countries, but in our temperate climate you can easily verify that any difference in the dip stick levels on a cold engine and warm engine are not noticeable. Having said that, a vehicles operating temperature will be more or less the same whether it is running in a tropical country or a cold country. Hence, to factor out the ambient temperature manufacturers suggest checking at operating temperatures.

Ah, yes, I was just taking a logical track bearing in mind the Delhi summers & winters. But an interesting thing I discovered in the manual was that at normal operating temperature, the engine oil is at 80-110 degrees Celsius. So, guess that accounts for the difference in cold engine vs. warm engine readings I mentioned above, inspite of our generally warm weather.

Originally Posted by Jaggu

Well i stated the facts that i know off. Have you measured the difference in oil dip stick level after warming up? Is it (the variation) same and consistent with all vehicles? And more importantly how much is it (quantity)?

So please read a post and understand clearly what it means before going ballistic on someones experience.

I apologise if I offended you - wasn't my intent. And I didn't really go ballistic, so again, sorry if that was your takeaway.

You didn't state any facts in your post, so not sure what you're referring to, but let me elaborate on the point I was trying to make.

I believe there is a place for personal experiences, more so of someone with your level of experience, but that place is in the subjective realm, say, your reading of a car's dynamics or daily life with a particular car. However, this is a technical topic, and here, there is only place for facts and, if at all, quantifiable personal experiences. So, steering a technical conversation into the 'i've been doing this for years' may not be appropriate, at least in my reading, and the reason I mentioned your moderator status was not to take a jibe at you but to point out that you have a greater responsibility than normal members to maintain the quality of conversations here.

Taking an example of your response in the current post, for example:

Originally Posted by Jaggu

Why while engine is cold? I don't like to burn my finger or hands to start with.

That is not really the science of engine oil checks, and for that matter, I've never seen anyone's fingers or hands burn while checking engine oil - but, I digress. All we're trying to do in this thread is to figure out the absolutely correct method of checking oil, not whether that burns peoples hands.

Originally Posted by Jaggu

Another interesting fact usually the dip stick will have about 1/2 to 3/4 liter as range and this is good enough buffer. They are designed also with ample buffers, if an engine takes 3 liter, it can run under full stress even with say 2.5 liters.

Again, you're narrating commonsense and accepted knowledge, and while I could be wrong, I believe the point of discussions on technical sections of the forum is to dabble in referenced facts and to expand our understanding. Take GTO's post above, as an example; made us question everything, and made us think on the fundamentals. And that is all I meant to point out in my original post.

Once again, apologies. I do hope you now understand where I was coming from.

[Jaggu]

Originally Posted by bosporus

I apologise if I offended you - wasn't my intent. And I didn't really go ballistic, so again, sorry if that was your takeaway.

Hey! no need for apologies, this is the problem with written communication tone understood by the receiver can be quite different to what is intended.

You didn't state any facts in your post, so not sure what you're referring to, but let me elaborate on the point I was trying to make.

Check owners manual! again missed it? those are the facts. Facts of car ownership, the basics, read your owners manual fully. Very few do it.

I believe there is a place for personal experiences, more so of someone with your level of experience, but that place is in the subjective realm, say, your reading of a car's dynamics or daily life with a particular car. However, this is a technical topic, and here, there is only place for facts and, if at all, quantifiable personal experiences. So, steering a technical conversation into the 'i've been doing this for years' may not be appropriate, at least in my reading, and the reason I mentioned your moderator status was not to take a jibe at you but to point out that you have a greater responsibility than normal members to maintain the quality of conversations here.

Point taken, but where are the technical rather quantifiable evidence i asked for? How much is the variation part ^^ has anyone in here measured it? Is it alarming, that we all should be concerned with?

There was no technical discussion apart from the owners manual detailing. So as a reply i stated my experience saying, "hey it is a rather simple thing". Follow some basics "less than mid level" check. Where is that trivializing it?

That is not really the science of engine oil checks, and for that matter, I've never seen anyone's fingers or hands burn while checking engine oil - but, I digress. All we're trying to do in this thread is to figure out the absolutely correct method of checking oil, not whether that burns peoples hands.

That was just dry humor. I missed posting a smile there, see the problem with written communication?!

Again, you're narrating commonsense and accepted knowledge, and while I could be wrong, I believe the point of discussions on technical sections of the forum is to dabble in referenced facts and to expand our understanding. Take GTO's post above, as an example; made us question everything, and made us think on the fundamentals. And that is all I meant to point out in my original post.

I do not agree to this... the amount of knowledge i have gained from this (TBHP) and various other online forums, from the personal experience / DIY experience done by people like you and me, has given me more info than to>> The articles out there- are mostly common sense stuff, which anyone with "some internet search sense" will first find, before getting into a technical thread.

Once again, apologies. I do hope you now understand where I was coming from.

Again no need for any apologies, just want to clarify that i am also a normal member like you, before my responsibilities of moderating this site.

so let the technical discussion continue

On the topic, i would still go with what owners manual says for this for regular oil checks, instead of debating hot Vs cold. Practical sense, always keep an eye out for anything less than 1/2 the dip stick level, hot or cold.

When it comes to complete oil change, it is little more interesting, especially since most often the change happens away from your eyes and you have no idea of oil quantity, unless its way above the max level. Only practical solution i found for this was either a DIY or carry your own oil, and insist on monitoring the change, while ensuring only the right amount is filled, that too after the old oil is drained off completely.

[bosporus]

Originally Posted by Jaggu

Hey! no need for apologies, this is the problem with written communication tone understood by the receiver can be quite different to what is intended.

so let the technical discussion continue

Thank you Jaggu, for taking it in the right spirit, and once again, apologies if I inadvertently offended you.

Originally Posted by Jaggu

On the topic, i would still go with what owners manual says for this for regular oil checks, instead of debating hot Vs cold. Practical sense, always keep an eye out for anything less than 1/2 the dip stick level, hot or cold.

Completely agree; the real correct answer is, check your car's manual, and check levels regularly

Originally Posted by Jaggu

When it comes to complete oil change, it is little more interesting, especially since most often the change happens away from your eyes and you have no idea of oil quantity, unless its way above the max level. Only practical solution i found for this was either a DIY or carry your own oil, and insist on monitoring the change, while ensuring only the right amount is filled, that too after the old oil is drained off completely.

True that. I've never monitored it personally, but always check the color of the oil & the level before taking delivery. It's not fail proof, but gives a decent idea of whether the job has been done properly.

---

On a separate note, this was the first time in 3.5 years, that the level in my Vento dropped at all. The engine oil level has never moved before, between services, and this is also the first year that I've done a lot of short trips (3-4km, one way), which VW describes as severe operating conditions, and cautions that it could cause engine oil usage of 500ml/1,000kms - uncannily precise, this.