- My model of MX-5 is: __mk3.5 09 1.8
- I’m based near: __n/a
- I’m looking for technical help or recommendations on: __Oil dipstick type and overfilling.
Hi all just a quick one,
Just picked up a 09 1.8 and loving it, the dealer mentioned they topped fluids up before I picked it up, had a check this morning when cold and it seems to be little over, marked in red in the picture below, would this level be fine or should I take some out?
Also I’ve seem some conversation around the new vs old dipstick but confused which is which, I’ve got the more cylindrical one rather than the flat one with the holes, is the flat one the newer one and easier to read/worth changing to?
thats where i keep my level and no problems
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Hiya, won’t do any harm I reckon? As BBB said, I usually have mine slightly over the top level mark. You have the ‘older’ style dipstick which is fine as it records the correct hi/lo oil levels the same as the revised version. I have the revised one and do find it easier to read though. Not expensive to swap over and you might feel happier with the later iteration. 
Barrie
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Or do as I did…drill two small holes, job done. 
generally overfilling an engine with oil is a bad idea, as it may make it leak, take longer to warm up etc.
to take that much out, I would just replace the oil filter 
but if it you have just got it from a dealer, - make them do it!
The real issue with overfilling is the oil gets whipped up by the crank into a foam and ceases to be effectively pumped and lubrication fails.
90% of people will say an over fill is fine. And of course the dipstick design has some tolerance to allow for poor measuring (car not on the level) as well as for slight overfilling.
Personally, I would drain some off. But I don’t know how much tolerance there is on these dipsticks. Plenty wiser people than me here may say it is perfectly fine. Some may even say you need to overfill it because the dipstick is too long. But if it was me, (been there and done that), I would drain some off and buy the better designed and easier to read dipstick.
There is nothing wrong with it, leave it alone.
Concentrate on more pressing matters like putting some miles on it and checking to see if it uses oil.
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If SERIOUSLY over filled then potentially yes.
Remember that as soon as the engine is started the pump picks up oil and sends it off to all the components. Obviously, the level will go down away from the crankshaft and not even be a problem.
The real problem is when there is not enough oil in there and the pump pick up becomes starved, (hence incorporated baffle plates) and then that’s when the real problems start.
Over pressure (leaks) wouldn’t be a problem really either with the crank case breather etc etc.
I would leave well alone.
That’s just my opinion too.
Hope you are enjoying your new home in Scotland. 
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Going off thread briefly… awesome in Scotland at the minute. Blue sky, fantastic sunsets, empty roads. Drove a couple of hundred miles top down in the mountains yesterday and tried (and failed) to climb Ben Lawer (North of Loch Tay). Truly awesome. So very happy so far. 
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Thanks all for the advice, I’ve gone ahead and got the newer style dipstick and it is much easier to read. Decided to leave the oil level where it is, as most have pointed out it shouldn’t be an issue and I’m most likely worrying about nothing.
On another note loving the car and the community, I’m actually based in south west wales around the pembrokeshire area and it’s been great taking the car down some of these roads, my only complaint is that I dont finish work until 6 during the week so dont get much time for a drive, but I’m definitely looking forward to the weekend!!
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On the NC for checking oil level I thought you were supposed to let the car get up to temp then switch off and wait 5 mins
That’s pretty much standard across the board for all engines (with a wet sump system) and including the ones without dip sticks. (I leave mine for about 15 minutes though).
As said you check the oil when the engine is warm.
It will always appear overfilled if you check it cold, as it’s all drained back into the sump.
Last paragraph is Edit - a difference of opinion. The oil will expand to a certain degree when warm/hot. Hence WHY you check it when warm/hot to obtain the correct level.
This being a science take on matters and not mine and which most people know.
“All three states of matter (solid, liquid and gas) expand when heated. The atoms themselves do not expand , but the volume they take up does. When a solid is heated, its atoms vibrate faster about their fixed points”.
Good Lord, what a load of utter rubbish! 
Hot or cold what’s the definitive answer??..this is like turret oil the debate will live on for ever.
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You can do both, I do but my preference is check the oil when stood overnight.
As I say my preference, it works, oil shows on the upper mark and that’s what I want to see.
Turret oil, it’s proven, put oil in an NC 5 or 6 speed turret and it’ll stay there, it does on mine.
It’s like asking what day of the week and at what time you should cut the grass 
I’ve never known any car group ever who devotes so much time to discussing a dipstick
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TBH I bought the new dipstick, I wasted my money, it still tells me the same thing. I never really had a problem with the original early stick.
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There you go, just proved my point.
You won’t get any definitive answer from him.
If you notice he will pick up on a post and just be rude and obnoxious, (My turn that day).
He doesn’t actually “Give an answer” to anyone who actually asks a specific question.
If he disagrees with a comment he doesn’t come back with an answer with any evidence to support “His Opinion”.
If he is not interested in “Dip Sticks” then why does he bother reading it?
You will never miss his workshop by the way, as you get close you will hear the Kelly Clarkson song “Mr Know It All” being played at full volume on constant loop.
Enjoy your weekend.
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