Oil - Questions

[xreyuk]

Thought I'd post on here at the risk of looking an idiot, as I'd prefer to do that than destroy a perfectly good car.

Read the manual on my mum's 1.6 petrol A3, and my 1.6TDI Seat Leon, about checking and topping up oil.

The A3 manual reads:

Park on a level surface
Allow the warm engine to idle briefly before shutting down
Wait 2 minutes, take out dipstick, wipe clean and re-insert dipstick, check oil level.

My Leon manual reads:

Park on a level surface
Idle the engine until it is up to service temperature
Then same as above.

I'm assuming that both of these mean to do it when the engine is up to the full 90c temperature?

I'm also assuming that when it talks about doing the topping up, it means to do that when the engine is at full temperature too, because it doesn't mention anything about temperatures when doing that, or does it not matter?

Finally, how long can I store the oil for, and is there anything I need to know about storing it?

[RJP001]

I wouldn't have thought that it would matter. More of a case that I'm surprised they have an engine run before you check the engine oil because then it's circulated all the way around the engine and will take time to fully drain into the sump again?

Storage wise I guess you can keep it for years if it's kept away from freezing and excess heat?

[Pothole]

you're only likely to be topping up when you've checked the levels after all that palaver and found them low, aren't you? The fact that manufacturers still use such a primitive measuring system would suggest to me that there's quite a lot of tolerance built in. You're unlikely to do any damage, just try not to overfill.

[steve singh]

xreyuk said:

Thought I'd post on here at the risk of looking an idiot, as I'd prefer to do that than destroy a perfectly good car.

Read the manual on my mum's 1.6 petrol A3, and my 1.6TDI Seat Leon, about checking and topping up oil.

The A3 manual reads:

Park on a level surface
Allow the warm engine to idle briefly before shutting down
Wait 2 minutes, take out dipstick, wipe clean and re-insert dipstick, check oil level.

My Leon manual reads:

Park on a level surface
Idle the engine until it is up to service temperature
Then same as above.

I'm assuming that both of these mean to do it when the engine is up to the full 90c temperature?

I'm also assuming that when it talks about doing the topping up, it means to do that when the engine is at full temperature too, because it doesn't mention anything about temperatures when doing that, or does it not matter?

Finally, how long can I store the oil for, and is there anything I need to know about storing it?

Coolant coming up to temp is not the same as oil coming up to temp...typically water at temp + 10 mins driving gets oil up to temp...

[littleredrooster]

Park on a level surface and it really, really doesn't matter whether it's hot or cold as long as it has stood for a few minutes for the oil to drain back to the sump. Do it the same way every time for consistency.

Oil can be stored in a sealed container for as long as you want, practicably.

[steve singh]

littleredrooster said:

Park on a level surface and it really, really doesn't matter whether it's hot or cold as long as it has stood for a few minutes for the oil to drain back to the sump. Do it the same way every time for consistency.

Oil can be stored in a sealed container for as long as you want, practicably.

So how do you know if your about to overfill, as i'm assuming if this car has a dipstick then the max mark would be calibrated to reflect the manufactuers procedure?

I think it's on the new beamers and porsches where you don't have a dipstick but the computer will not give an oil level guide until the car is warm...

[Mave]

The max mark is calibrated around all the oil draining back to the sump. Warming it up first means it'll drain back quicker, but the fact that you've actually run the engine means you need to leave time for it to drain back. I've always checked mine stone cold when its been left overnight, never had a problem.

[steve singh]

Mave said:

The max mark is calibrated around all the oil draining back to the sump. Warming it up first means it'll drain back quicker, but the fact that you've actually run the engine means you need to leave time for it to drain back.

So you do what i said, follow the manufactures recommended procedure

[Mave]

steve singh said:

So you do what i said, follow the manufactures recommended procedure

Not neccesarily, you make sure you understand the reasoning behind the manufacturers procedure, then adjust it to fit in with what suits you best (while still meeting the intent). If I want to check the oil before I go on a long journey, I'm not going to follow the procedure and wait for the oil to get warm, just so I can wait for it to drian back down again

[Mave]

steve singh said:

So how do you know if your about to overfill, as i'm assuming if this car has a dipstick then the max mark would be calibrated to reflect the manufactuers procedure?

The procedure littleredrooster wrote will give you the same result as if you followed the manufacturers procedure because the oil is in the same place.

Edited by Mave on Friday 14th December 19:12

[steve singh]

Mave said:

steve singh said:

So you do what i said, follow the manufactures recommended procedure

Not neccesarily, you make sure you understand the reasoning behind the manufacturers procedure, then adjust it to fit in with what suits you best (while still meeting the intent). If I want to check the oil before I go on a long journey, I'm not going to follow the procedure and wait for the oil to get warm, just so I can wait for it to drian back down again

But if you don't follow the process the max mark on the dipstick/electric guage is no longer relevant as it's been calibrated to reflect the manufactuer process - do you see the circular reference of your argument ?

Of course, if you follow the manufactuer procedure and then the next day knowing the oil is spot on do your own procedure, then yes you establish a new benchmark and work off that...

Etc


Etc

[ging84]

just follow what it says in the book
some, or most engines it may not make a real difference, but you might have one which there is good reason to check it in a particular way.
for example some cars have some very flimsy dip sticks, which become much more likely to snap off if you pull them out of a really cold engine

[Liquid Tuna]

steve singh said:

But if you don't follow the process the max mark on the dipstick/electric guage is no longer relevant as it's been calibrated to reflect the manufactuer process - do you see the circular reference of your argument ?

Of course, if you follow the manufactuer procedure and then the next day knowing the oil is spot on do your own procedure, then yes you establish a new benchmark and work off that...

Etc


Etc

Dude!! Come on! It's not that critical. You don't have to weigh the atoms!! Just get the oil between the two marks and keep it there. Try not to overfill it and don't let it drop below the minimum. For "most" cars that will be sufficient for the engine to out-live the rest of the car. It won't explode or terminate 10s of thousands of miles before it should, just because you put +/- 50ml of oil above or below the manufacturers procedure.

[steve singh]

When you have a porsche you do tend to get obsessed with oil given how crap their engines are.

Anyhow it's a moot point - most modern day cars only have dipsticks behind the steering wheel with the world of electronics we are now in!

[Mave]

steve singh said:

But if you don't follow the process the max mark on the dipstick/electric guage is no longer relevant as it's been calibrated to reflect the manufactuer process - do you see the circular reference of your argument ?

Of course, if you follow the manufactuer procedure and then the next day knowing the oil is spot on do your own procedure, then yes you establish a new benchmark and work off that...

Etc

Etc

I have never followed the manufacturer process to establish a benchmark.
I know that the intent of the manufacturer process is to allow all of the oil to drain back to the sump before you measure the level.
Whether the engine is hot or cold, whether you wait 2 mins, 5 mins, 10 hours or a week makes no difference to the measurement as long as it's not sub zero or you're on a hill

[steve singh]

Mave said:

steve singh said:

But if you don't follow the process the max mark on the dipstick/electric guage is no longer relevant as it's been calibrated to reflect the manufactuer process - do you see the circular reference of your argument ?

Of course, if you follow the manufactuer procedure and then the next day knowing the oil is spot on do your own procedure, then yes you establish a new benchmark and work off that...

Etc

Etc

I have never followed the manufacturer process to establish a benchmark.
I know that the intent of the manufacturer process is to allow all of the oil to drain back to the sump before you measure the level.
Whether the engine is hot or cold, whether you wait 2 mins, 5 mins, 10 hours or a week makes no difference to the measurement as long as it's not sub zero or you're on a hill

Porsche and BMW (as examples) only give you an electronic indication once the car is up to operating temp as opposed to before - why would they do this? Because they've calibrated their system to the oil being a certain temperature - if you take a reading from "cold" then you could be anywhere on the temp scale (cold in russia is different to cold in dubai etc.), however a reading at say 90 degrees will always be consistent as oil is at certain level at that singular temp reading.

It true that it's not an exact science and cars have tolerances - but you do risk overfilling a relatively modern day porsche or beamer if you started to take a dipstick reading from a non manufacturer suggested method and then start topping up to the maximum line (that said most of the latest cars don't have dipsticks).

Currently we're experiencing temps of minus 5 degress, a couple of winters ago it was double digit minus levels - i would strongly suggest to the op that i would follow the manufactuers procedure before adding any oil to get back to the maximum.

In pragmatic terms the key thing is that car is at least level and you've waited a couple of mins for the oil to reach the sump.

[Mave]

steve singh said:

Mave said:

steve singh said:

But if you don't follow the process the max mark on the dipstick/electric guage is no longer relevant as it's been calibrated to reflect the manufactuer process - do you see the circular reference of your argument ?

Of course, if you follow the manufactuer procedure and then the next day knowing the oil is spot on do your own procedure, then yes you establish a new benchmark and work off that...

Etc

Etc

I have never followed the manufacturer process to establish a benchmark.
I know that the intent of the manufacturer process is to allow all of the oil to drain back to the sump before you measure the level.
Whether the engine is hot or cold, whether you wait 2 mins, 5 mins, 10 hours or a week makes no difference to the measurement as long as it's not sub zero or you're on a hill

Porsche and BMW (as examples) only give you an electronic indication once the car is up to operating temp as opposed to before - why would they do this? Because they've calibrated their system to the oil being a certain temperature - if you take a reading from "cold" then you could be anywhere on the temp scale (cold in russia is different to cold in dubai etc.), however a reading at say 90 degrees will always be consistent as oil is at certain level at that singular temp reading.

It true that it's not an exact science and cars have tolerances - but you do risk overfilling a relatively modern day porsche or beamer if you started to take a dipstick reading from a non manufacturer suggested method and then start topping up to the maximum line (that said most of the latest cars don't have dipsticks).

Sure, if you pour a litre of oil in and don't wait for it to drain to the sump you'll get an inaccurate reading. But if you've left it overnight then the effect of thermal expansion even in teh coldest of winters will be negligable.

[littleredrooster]

steve singh said:

Porsche and BMW (as examples) only give you an electronic indication once the car is up to operating temp as opposed to before - why would they do this? Because they've calibrated their system to the oil being a certain temperature - if you take a reading from "cold" then you could be anywhere on the temp scale (cold in russia is different to cold in dubai etc.), however a reading at say 90 degrees will always be consistent as oil is at certain level at that singular temp reading.

It true that it's not an exact science and cars have tolerances - but you do risk overfilling a relatively modern day porsche or beamer if you started to take a dipstick reading from a non manufacturer suggested method and then start topping up to the maximum line (that said most of the latest cars don't have dipsticks).

Currently we're experiencing temps of minus 5 degress, a couple of winters ago it was double digit minus levels - i would strongly suggest to the op that i would follow the manufactuers procedure before adding any oil to get back to the maximum.

In pragmatic terms the key thing is that car is at least level and you've waited a couple of mins for the oil to reach the sump.

Utter nonsense. The difference in volume between boiling oil and sub-zero oil would be completely unmeasurable on a dip-stick or by a level sensor. How much do you think it expands and contracts?

[Ozzie Osmond]

littleredrooster said:

Utter nonsense. The difference in volume between boiling oil and sub-zero oil would be completely unmeasurable on a dip-stick or by a level sensor. How much do you think it expands and contracts?

I'm glad somebody else said that before I had to!

Several things are absolutely clear,

• Oil level is generally not critical.
• Cars can be parked and driven on slopes without exploding - so there's leeway.
• Overfill is a bad thing - especially in horizontal engines. (Beetle, Porsche, Subaru)
• Underfill is generally irrelevant so long as there's some in there for the oil pump to pick up. But the less you have in there the more work it gets.
• Simply using a bit of oil never did an engine any harm. Many engines will burn a bit as they get older. It leaks past the piston rings and may come down the valve guides.
• Fresh oil from regular top-ups is a good thing for older engines.

Above all, modern fully synthetic oils are virtually indestructible. So ignore the "PH myth" that extended service interval will kill your engine.

Buy decent oil, although precise grading isn't critical. The numbers mainly refer to atmospheric temperature range but, lets face it, once your engine is warm its always the same temperature inside!

[V88Dicky]

Generally, and as has already been said, as long as the car's on a flat surface, then you'll get a reasonably accurate reading (providing the engine hasn't just been shut down).
Personally, I just check in the morning when the car has stood overnight. For my Monaro, I keep the oil just below the max level, and I mean just, to allow for thermal expansion. There's bound to be some in 6.2 litres of 5w30!

Older cars, if using a bit of oil, like my old Fiesta was, try using a thicker grade oil. I went from 5w to 15w and it cure it's oil consumption habit