Checking oil - tips?

RE: Checking oil - tips?

• Check the oil level when the car is parked on a flat/level surface.
• Always try to check the oil when cold at the start of the day if possible when it is thicker and will cling to the dip-stick (d/s) better.  Pull the d/s, check, wipe, re-insert the d/s slowly and check again.  Avoid pushing the stick in too fast as this can cause a falsely higher oil level reading.
• If you are on a long run and the engine is hot, fill up with fuel, park up and switch off.  Wait 10 to 15 minutes to let the oil settle back to the sump.  As above, check twice and insert the d/s slowly for the second check.
• If you are struggling to see the oil level on the stick because of bright sunlight, hold the end of the stick against some white  tissue as this will highlight where the oil is at on the end of the d/s.
• There should always be a light film of oil on the d/s end even when it is hot, if not, then the oil level is low, or you have not re-inserted the d/s properly.
• DO NOT OVERFILL if topping up.  The engine should take no more than 0.75L to go from LOW to HIGH on the d/s.
• Check the condition of the 'O'-ring seal on the d/s as this will allow fumes into the engine bay if damaged.
• DO NOT CHECK the oil level with the engine running.  Whilst you should be ok putting the d/s back in with it running that is no guarantee and is not safe practice.

Mazda recommend starting the engine and letting it idle to warm-up to normal operating temperature, then switching off and waiting 5 minutes.  Not the best way IMHO, but never check the oil level immediately after switching off as it takes a while for the oil to drain back to the sump to get a proper reading.

Service intervals are largely driven by market demand.  In the USA, drive through "Lube-Stations" are common, and an oil and filter change is a 10 minute exercise for very little cost, so OCIs (Oil Change Intervals) tend to be shorter.  The same applies in many other countries where oil and fuel is cheaper.

In Europe and predominantly the UK where there was, at one time, a large fleet of commercial vehicles on the road, fleet managers wanted their staff on the road selling to clients and not sat in dealerships getting cars serviced.  In addition, oil technology moved on leaps and bounds such that OCIs started to double from the 6k miles of the 90s to 12k miles by the beginning of this last decade and now 24-30k miles is a possibility with the caveat that the oil used must be of the highest possible quality.

Why do people in the US think it is necessary to change the oil so often?  Because that's what their father did? Maybe?  But mainly because they think it is important to drain out all the contaminants and wear debris material.  Well, of course, that is true if you have an old engine, that's worn, and has a carburettor and a distributor - all very good at the time but very mechanical and subject to going off tune quite quickly.  Modern cars do not go off tune quite like they used to, so they run much more efficiently and don't produce the contamination that they used to do, and the quality of the oil is better so the wear debris is not as bad as it used to be, so there's no need to drain the oil as frequently as one used to do.

A number of cars use a software algorithm that attempts to calculate the oil quality based on hard or how litte you have driven the vehocle and this works quite well.  I have seen on a previous car that the miles remaining hardly moves when cruising at 65mph, but on the Autobahn with the pedal flat down cruising at 130mph, the miles remaining were dropping at the rate of something like two for every mile covered.  Higher priced executive cars actualy have a sensor that determines when the oil quality reaches an end-point.

There's more paint drying to be seen at: http://www.kewengineering.co.uk/Auto_oils/oil_degradation.htm

Mazda5 & MX5 LE

1969 MGB GT & 1968 MG1300

RE: Checking oil - tips?

Thanks again Martin.  it's interesting that you say to check when the car is cold, as I'm sure it's the warm oil that makes it difficult to read the dipstick because it all runs off as you draw the stick out.

Why do you think Mazda say to do it after the car has been warmed up to operating temp and left for 5 - 10 mins?

Why do you think it's better to check when cold instead?

Otherwise, I think you've pretty much covered everything!

RE: Checking oil - tips?

13/01/2010 08:08:07, Mazrus said:
" 

Why do you think Mazda say to do it after the car has been warmed up to operating temp and left for 5 - 10 mins?

I assume Mazda suggest this method as it gives the most consistent reading. 

I think it's a waste to warm up the car just to check the oil, not very environmentally friendly.

When the engine is cold, usually the oil will all have drained back to the sump and as I mentioned above, when it is cold the oil is more likely to cling to the d/s.  Obviously this won't be the case if you had just driven down the motorway and stopped at the services, so hence in that case leave it to stand for 10-15 minutes first if you feel the need to check the oil level.

RE: Checking oil - tips?

Hmm, I really ought to check mine more - Fifth Gear did a piece about oil, whereby Tim Shaw went round a local supermarket car park checking peoples oil for them and topping-up any that needed it, which most did.  In fact, most were perilously low!

RE: Checking oil - tips?

Good reply that Martin if you don't mind me saying and I totally agree on the MX with the 'dipstick designed' dipstick it is way better to check when stone cold simply because it is much easier to get a dependable level.

Another point with checking the dipstick seal is if this allows air in it will give a slightly weaker mixture (probably only noticeable at idle) due to the crankcase ventilation system drawing more 'unmetered' air than the ECU is programed for.  I'm being picky as it would probably sort itself out on a modern closed loop system but something to bear in mind if you get a rough idle.

Bear in mind with the American OCI model that many of their indigenous creations are from another era compared to what the rest of the industrial world are used to.  For instance their 'sports' cars still tend to use live rear axles, we moved away from this just after the Romans left us, their engines are not much better (although I do love a 2 valve cross plane crank V8).

RE: Checking oil - tips?

Thanks, GDCobra and as you have probably gathered, lubrication is my thing, on an industrial maintenance level for my job and on an automotive level for my hobby.  Glad to be able to contribute to the community.

MazRus, I think I saw that episode, and yes, a little worrying! 

RE: Checking oil - tips?

Yeah, it's worrying, but I find it difficult to believe that all those cars would've died of engine failure.  They estimated something like 60% or more vehicles on the road don't have enough oil in their engines, but if that was true you'd expect to see considerbly more vehicles broken down at the side of the road and would expect to hear of lots more problems that people had experienced.  Still, I oughta start checking mine more, and switch over to a better oil.

Now, what to choose?!  And what do you do about the service history if you service the car yourself?

RE: Checking oil - tips?

14/01/2010 08:46:33, Martin said:
"

Thanks, GDCobra and as you have probably gathered, lubrication is my thing, on an industrial maintenance level for my job and on an automotive level for my hobby.  Glad to be able to contribute to the community.

Me too, but bear in mind much of it would probably have been set up (just like TG), these programs never let reality get in the way of telling a good story! I can't believe the attitude most people have to oil, it is one of the few things you can influece on a modern car which will effect its longevity, as a friend of mine from the local garage is always telling me it is the life blood of your engine.  I may go OTT by using quality oil more often than necessary but I'd rather have too much than too little and (when warm) I do like to drive my car hard and I do track days now and again and even so it costs me less than <£100 per year.

RE: Checking oil - tips?

What engine does your car have GD?  And what oil do you use?

I never track my car, but do like to drive it hard when possible, so want an oil that can give max protection all year round.  (Oh, and I am in the UK, by the way.)  What should I go for in my 2.0l?

Also, I only do 7000-ish miles a year, one week on, one week off (I lift share to work) so the car is unused every other week, but used daily on the opposing weeks. (Though I doubt this makes much difference.)

And is it worth changing my oil more than once a year with such low mileage?

Plus, I'd like to do my own oil, (more for making sure that my specified oil goes in and no spanner monkey rants my car to the burger van at lunch time, than because of cost) but want to keep a full service history... how?!

RE: Checking oil - tips?

I wouldn't bother with a mid-year oil change if you're only doing 7000 a year, in-fact as I use Mobil 1 I wouldn't bother with it on my own car (at just under 12,000) if I wasn't driving hard most of the time and on the track some of the time, even that is probably OTT as according to Mobil this should be good for over 20,000 but for an extra £50 I see it as a good insurance policy.

I think you are doing pretty good mileage in that although you are doing a low overall mileage it is made up of reasonable length trips (when you are driving the car you're doing more miles than me), this is better than a low mileage made up of a high number of short trips in my book.  I'd not get too paranoid about the oil though, if you're keeping it topped up (I never have to fill mine) with any decent quality oil you won't go too far wrong, put Tesco special in though and who knows what may happen.

I'd try and find a garage which will do the change while you wait and preferably watch (as I do).  Changing oil can be quite a messy job and awkward unless you have a ramp of pit and one which any half decent mechanic would find had to bollox up (I know I'll regret that!).