MEGAREDS

For those interested, see these threads...

Foamy/Milky Oil No. 1

Foamy/Milky Oil No. 2

Foamy/Milky Oil No. 3

SnyderMazz

I have been told by my master technician who was told by the Mazda Technical hotline, that the condensation on the dipstick and the oil being that color is NORMAL with the vehicle. The exact reasoning and cause of it I dont know.

MikeS

I also have the condensation in the oil. My dealer said they called Mazda engineering and was told that it is "normal" and will not cause damage to the engine. I still plan to change the oil regularly in the cold months. It has been barely above freezing during the day the last 2 weeks.

I notice that when I get the car out on a highway cruise for an hour or so, the stuff gradually goes away.

A friend suggested blocking off the oil coloer in the cold months. Anyone try that?

inittab

It's called "lung mustard"

Yes, long drives will clear out the water condensation and the white stuff. My 85 RX-7 never gets this because my commute is 40 miles one way. Cars that are only driven short distances will see this in the oil

EDIT - And do NOT block your oil cooler. That's bad advise IMO.

cruzdreamer

I still get it in my oil......in the beginning I had it looked at to be sure....said not to worry about it! So I won't worry...weird though. 3200 miles and running good so far!

FirstSpin

Anyone on here have a mechanical understanding of where this water comes from? (I'm assuming byproduct of combustion). But how does the water get into the crankcase? Just curious.

If it ever happens to me, I'll take a sample to work and have the percent water analyzed. It won't hurt to have a feel for just how much water is present. So far, my oil is water-free and to be honest, I hope to hell it stays that way.....

klegg

That would be wonderful..I can not figure out how water gets into a sealed system..

Oldsnwbrdr

This forum is just awesome. I was checking my oil today (just <4,000 miles) and noticed that the oil was a light brown color and was very frothy. I panicked and filed a mental note to get an oil change ASAP but after reading this thread I guess I have no cause for alarm, other than the fact that the consistency of the oil made it impossible to check the oil level.

Folks, we have a very bizarre automobile. This and spinning the tires at 8,500 rpm are the two weirdest ownership experiences I've had with the baby.

Rotary Nut

I too had that crap on the dip stick. I changed my oil this weekend and although there was copius amounts on the stick there was no indication of it in the oil whatsoever! I rechecked the oil level today and the amount present was next to nothing so I'm not going to worry about it.

Draig

When I check my oil, I find some creamy "mayonaisse" on the dipstick and filler cap too.
I reported this to my local dealer who passed the issue to Mazda technical. Their response is that it is due to condensation in the oil as the engine doesnt get hot enough to evaporate it. As these are the furthest points from the heat, this happens. They say they are not concerned about it but going back to the old days when this stuff meant your gaskets were in bad shape, I am a bit concerned that when the car is eventually sold, then a potential buyer would be put off.
It still isnt clearing and they are sending the issue back to Mazda again. They think its the weather. Does anyone from the hotter climates get this problem too?

Mike

klegg

Mine only started when the temp went below 50....but will water cause long term problems with the seals or the inside of the chamber?

FirstSpin

Condensation implies that there's water vapor available to condense. Where's the water vapor coming from? I'm assuming the crankcase is similar enough to piston-crancases, in that it's a sealed chamber with 3 points of potential exposure to the environment; a fill-cap, a dipstick, and a drain-bolt. That being the case, why doesn't this "condensation" occur in oil that lubricates conventional engines?

It's obvious that water is generated when gasoline in burned but in a piston engine that water would presumably be a part of the exhaust. Does the rotary allow some of that "steam" to seep past the seals and thus wind up in the oil reservoir? It makes no sense to me. Another thing that's strange is that the one member found this froth on the dipstick yet found none in the oil when he drained the pan. Emuslified water in oil is heavier than oil itself. The difference in density being slight, it would probably exist as a relatively even dispersion all throughout the oil. If separation were to occur though, the emulsion would sink, NOT float. Therefore, you'd think the member would have seen the stuff at the bottom of the oil pan.

The fact that it's foamy and it floats almost suggests that it's gas-cut. This would essentially mean that it's been sheared in the presence of a gas (during combustion?) and has somehow managed to hang onto that gas and form a foam. Of the two, this one would seem the most innocuous given that water in the oil will change its rheological and lubricating properties.

Has anyone collected enough of this stuff to get a good look at it? Even if it's an oil and water emulsion, it should break (separate into 2 distinct phases) given time. It would be interesting to know if anyone has actually ever SEEN the water (after it separates from the oil) or if the the conclusion that this phenomenon is caused by water is merely an assumption.

realdeal

i just checked my oil and had this white stuff. I never had it before, but since i got the new oil pan it just now showed up. Is it possible the new oil pan is partly responsible?

klegg

[QUOTE]Originally posted by FirstSpin
[B]Condensation implies that there's water vapor available to condense. Where's the water vapor coming from? I'm assuming the crankcase is similar enough to piston-crancases, in that it's a sealed chamber with 3 points of potential exposure to the environment; a fill-cap, a dipstick, and a drain-bolt. That being the case, why doesn't this "condensation" occur in oil that lubricates conventional engines?

It's obvious that water is generated when gasoline in burned but in a piston engine that water would presumably be a part of the exhaust. Does the rotary allow some of that "steam" to seep past the seals and thus wind up in the oil reservoir? It makes no sense to me. Another thing that's strange is that the one member found this froth on the dipstick yet found none in the oil when he drained the pan. Emuslified water in oil is heavier than oil itself. The difference in density being slight, it would probably exist as a relatively even dispersion all throughout the oil. If separation were to occur though, the emulsion would sink, NOT float. Therefore, you'd think the member would have seen the stuff at the bottom of the oil pan.

The fact that it's foamy and it floats almost suggests that it's gas-cut. This would essentially mean that it's been sheared in the presence of a gas (during combustion?) and has somehow managed to hang onto that gas and form a foam. Of the two, this one would seem the most innocuous given that water in the oil will change its rheological and lubricating properties.

Has anyone collected enough of this stuff to get a good look at it? Even if it's an oil and water emulsion, it should break (separate into 2 distinct phases) given time. It would be interesting to know if anyone has actually ever SEEN the water (after it separates from the oil) or if the the conclusion that this phenomenon"



Wow, good post..I have never ssen it seperate, but I will see if I can try to get an answer. The car is going in for an oil change now, maybe I can look at the old stuff..

bay

yah this happened to me too, it was dang cold out in the NJ/PA area. i was running low on oil, the light was doing the blinky blink, so i went to a service station and changed the oil.. the froth boggled me for a second, id been driving for about 2 hours before..

i got an oil change and haven't checked it since, but from what this seems, its probably still doing it.

93rdcurrent

Mine does the same thing. I am not certain that it is water either. I have the distinct smell of fuel in the oil. I changed my oil originally at 2100 miles but decided that I will go off of the owners manual at 7500 for future changes unless I am going to auto x it or something. This is the first time I have seen more than just a little bit on the stick (the whole stick was covered just like the 2nd pic in the thread). I have 6k miles now. My guess is that it has to do with the apex seals and the lubricating oil. If the pressures were enough some of the mixture may be able to make it back in.

I know that in my other cars this would mean a blown head gasket and the whole oil would come out looking like this if you were driving on it. Not just around the dipstick. Very puzzling.

cruzdreamer

Checked oil today....had lots of condensation.......had the car since November. Did anyone in the warmer climates have this? I won't worry about it though! Nice technical comments Klegg & Firstspin!

MikeS

If you look closely, you can actually see some distinct water droplets on the upper part of the dipstick. I noticed taht today.

It does boil away if you get it on the highway, so I'm not concerned that it is antifreeze/water. Anyway, my coolant level has not droped a bit.

cvan707

I noticed the same thing this past weekend here in Dallas. Although we are further south than some of you it has been cold (40's daytime--20's night time) for us. It doesn't seem to affect the performance and I did not note any fuel smell to it.

Gord96BRG

That's a pretty big assumption (sealed chamber) - and a wrong one. It is just the same as piston crankcases, in that it's ventilated. In olden days, crankcases were ventilated to atmosphere, and were the source of much pollution. Nowadays (ie for the past 30 years!), crankcases are vented back to the intake system so emissions (oil vapours) are passed through the combustion chambers. Think about the heating that takes place in the crank from cold to full operating temperature - if it were sealed, you'd be varying between positive crankcase pressure (as the air heated up) to vacuum (as the air in the crankcase cooled down). Either of those would drastically affect operations, in the form of internal resistance to the rotating assemblies and in oil combustion from oil being forced past the rings/seals.

So - the crankcase is vented, and air does get pulled into it - after you turn your engine off and as it cools. That air contains a certain humidity level, which results in condensation. The reason it produces foam that is concentrated in the dipstick is probably due to the air circulation patterns within the crankcase caused by the rotating assemblies. BUT, it does happen with piston engines as well, and that's the main reason that short trips qualify for inclusion in the severe duty maintenance cycles with increased oil change intervals. In both piston and rotary engines, a long trip which lets oil temperatures stabilize at full operating temperature (above water's boiling temperature) will result in the water condensation getting turned to vapour, which gets cycled through the PCV valve to the intake and burned off.

Some condensation will always result from shutting down a hot engine - the issue is that if you make a long run the next time the engine runs, the condensation burns off right away. If you make a series of short runs where the engine never gets fully hot for a while, then the condensation doesn't burn off completely, and more accumulates at each cooldown. Again, this is the same for piston and rotary engines - it just seems that something about the rotary crankcase design results in it showing up as foam around the dipstick.

Regards,
Gordon

klegg

Wow, thanks GORD..

Winning_BlueRX8

Dang, Gord knows his stuff. Well Gord, maybe you can help me out. The body shop flooded my car and it was serviced at a dealership. Anyways, they swapped out the plugs for the "hot" ones, and changed the oil. I've noticed the milky white stuff on my dipstick, but I can smell gasoline in it. The smell is pretty noticeable. Is this normal or should I change my oil? I've only put about 700 miles on the car with the current oil in it. The service tech advised me that that oil change wouldn't be covered under warranty. He also told me that if there was a contaminate in the oil (ie, gas), that the ECU would throw a CEL. So what do you think?

bungobuns

Greeting from Scotland!

Well my velocity red RX8 has developed the fault from day one. At first I thought it was grease on the dip stick when it was new.

The Mayo became more apparrent at 500 miles. The car has not lost any coolant. And has now only covered 650 miles.

I can however comment that the mayo in my engine is not just foam, it also has jelly like salad cream deposits.

I have never had to add to the oil. So the car is running on factory supplied oil.

The problem seems to have manifeted when the temperatures dropped below zero.

The vehicle is driven for a minimium of 20 mins to work. It only takes 5 mins to reach temperature. So for 15mins the car is running at normal temperature.

I have opened a bun fight with Mazda UK on this issue. They confidently stated verbally, that water in the oil does not matter. I beg to differ as this will make the oil become acidic. Further it will change the ability of the oil to convey heat. In addition the water content will support oxidisation. Further the Oil mix will expand at a differrent rate from normal oil.

The oil and water mix will have a different viscosity. So lubrication has to be effected on start up. I expect that my engine will suffer more wear at this time than one with normal oil.

I note that the mazda runs on a comparatively 'runny' oil compared to ordinary combustion engines, not custard.

I would expect this custard to clog components of the engine. I am unclear of the size of the jets on the rotars for instance. Or even of the delivery system.

I have today, asked them for written proof that Mazda have verified this on an actual engine, and aren't shooting from the hip as I suspect.

I do not accept the argument of the engine being unsuitable for short runs. This was never a condition of sale of the vehicle. Infact I can't recall any car of this nature in the uk.

If this is Mazda's official line then sadly the RX8 is unsuitable for road use in a colder climate. I would expect a full refund, or atleast a modification to preheat the oil. (I seem to recall the VW Golf Mrk2 GTis having this facility?!!).

I can say I have never experienced this on any car that I have owned over the last 15 years.

On the positive side if it is infact okay to have mayo oil, then just think how much you can save by topping up with good ole tap water instead of oil.

Cummon Mazda pull your socks up on this issue, stop hidding behind the call centre girl, talk to us guys, we wont bite much!

I don't really care what is causing the mayo, the problem is unacceptible. I expect Mazda to acknowledge and rectify the problem, otherwise refund my car in full. I have other issues with my car. This mayo problem was the final straw. Shame as the Rx8 is a fabulous design, and drive.

Spin9k

I found the foamy stuff this weekend, took near 10 minutes to figure out (I think) that I needed to add 1/2 litre of oil.

I really don't care about the foam (that's a Mazda probelm if anything comes of it), I just care it is so hard to tell what the oil level is.

After all the car runs perfectly well.

GTF-RX-8

Just noticed the foamy stuff on my dipstick today.
In most cars it is usualy an indicator of a cracked head but it seems that alot of people here are experiencing it. I'm still going to alert the dealer.

The original poster indicated that the oil had a gas odor to it. Mine has the same. No one addressed that in this thread though.
Anyone else notice the same?

Gas odor in oil usually indicates flooding or super rich running motor.

Any thoughts?

Gary