I know there have been numerous threads regarding the topic of condensation forming in the oil filler neck due to the oil not heating up enough during short drives in cold weather, which describes the drives I've had recently. I noticed a sludge similar to that described in these other theads in my oil filler neck and wanted to make sure that this is the same stuff and not the result of coolant leaking into the oil, since I have a small coolant leak.

Here's the picture. (Nobody hurled in the oil, I swear!)

 

wow ive had a small case of what your talking about and it was NOWHERE near that bad looking. I also didnt get a light to shine all the way down to see, but hopefully somebody will chime in to answer.

 

hmm. Is a new rebuild? Alot of times we use vasoline to make the seals stick during assembly and you get some crud. That looks different. Anybody help this guy? Like to know myself. G

 

It's the original engine with around 52,000 miles. It seems to be running fine, at least for now but yeah, it looks like a disease. Any help/advice would be greatly appreciated.

 

That is "normal" condensation sludge buildup that usually burns off once you run the car and get the engine up to proper operating temps for an extended period of time.

 

ummm, not sure but seems to me that the oil change period is not properly scheduled. sludge usually occurs when you have NOT change oils in a while. As we all know our cars, mostly people recommend changing our oils every 2-2.5k miles.

 

Hmm. I've had the oil changed religiously every 1.5k miles. There's about 500 miles to go until my next scheduled change. I might just have the oil system flushed and have fresh oil put in and see if this problem occurs again. Thanks for the imput - any further comments are welcome.

 

Oil sludge formed by oxidized oil breakdown and contaminants is different than the condensation sludge in the photo. The milky appearance signals the presence of moisture in the oil film. Sludge buildup formed by oxidized oil is dark and gel-like in appearance.

 

What is the recommended way to reduce oil condensation? Should I just drive the car for an extended period of time so as to cause the oil to heat up?

 

Yes. You need to get the oil hot enough that it "boils off" the moisture that condenses inside the engine.

 

She needs a deuce!

 

I know that some condensation is normal, but that looks like some funk down below the filler neck. If it looks fine when drain the pan I guess that is all it could be.

 

hey guy, i guarantee you have a bad water seal. thats the first sign.

 

Gotcha. Thanks for the info everyone. I've decided that this is beyond my very limited capabilities and to therefore take the car in to have this and a suspension/rear diff rattle sorted out.

 

lol, there should not be that much coolant in your oil, disappointed in some of the responds you got about that, but thats a great sign of a bad coolant seal inside of your engine. A little of that is ok as rotary's almost always has a little blow-by specially on a newly rebuilt engine but thats.... really.... bad... I wouldn't drive on it at all because that goo wont lubricate like you want it to. I've seen similar in a minivan that was improperly put back together when the guy got a coolant and a oil line switched up. If you've had work on your motor recently to were they might have done that then its a possibility.

Someone also might have put coolant in your oil? If thats the case you should dump all that out, buy about 10 quarts of cheap oil and 5 of the stuff you would normally use.... Fill it full twice and just dump it out, on the second time turn your car on for a little bit to cycle it through dump it then put in your regular stuff....just flush the system as well as you can.

Theres no real easy way to fix it if its a coolant seal it means you have to separate the rotor housings from the irons and that means rebuild. You might not have to get new apex seals if there still within tolerances but you'll have to get a full gasket set for that at least. About 300-500 bucks.

This is assuming its a coolant seal but im willing to put my money on it.


Good luck man! hope someone just put a little coolant in your oil!

 

Very informative post DriftTrix. I've taken the radiator cap off to check out the coolant and there's no sign of oil. If a coolant seal had gone bad would there be oil in the coolant? Also, the oil on the dipstick seems fine, not like the milkshake in the filler neck. I've stopped driving the car and hope to get it into a rotary specialist soon to have the problem looked into further.

 

i use to get that as well, b4 i had a lot of city driving, constant on/of and changed my oil 3000 miles. Must be the constant driving a few blocks and turning it off. I agree with the previous post about not letting your car get hot enough to burn off the moisture. I don't drive much in the city now and i don't get that mayo effect, nothing beats driving 50 miles on the freeway to burn off moisture and changing ever 2000miles

 

If drained oil looks ok, just clean out crud with rag over bottle brush. verify that:

> mazda 3-way 180F t-stat is used
> cooling fans are not on full time, or set to come on below 200F (based on your usage)
> crud doesn't come back soon

Make sure to get a good run in every few days.

I had a headbolt break on another car ... looked like I stuck dipstick in a milkshake