why is my oil so dirty?
 

It seems like the oil in my car was pretty dirty when I changed it. was the 1st time since I have had the car for the last 90 days. dont know how much maintenance was done on the car.

original motor 93,000 on it now. Is my motor that full of gunk and how do I clean it out without causing massive problems?

runs fine no that I have the exhaust sealed.

I am thinking about switching to Royal Purple next time. I always used synthetic in my 79& 85 RX7.

sorry for the lame question. already searched. will try again.

Are you serious? Probably because it's been god knows how long since it was changed last. I mean, you answered your own question there.

Well, if the oil in the engine hasn't been changed in a long time, good thing that you did. The reason the oil is dirty shorty after the oil change is because there is still about 2 quarts left in the system. Since the oil change has been neglected, I'd run some engine cleaner and then drain the oil again. You need to change the oil more often especially in a rotary due to the oil injectors. The opening in the housing is VERY small and any debris will clog it.

Just thought of another issue. You may have loads of carbon in your engine. Even religiously changing oil will build carbon in your combustion. It's due to the ash content in the oil. That can't be helped. Do a search on "oil" and it shows you which oil has the lowest ash content. I had it pasted somewhere in the forum about a year back. Good reading.
Search the forum for ATF .

the oil right now isnt dirty. I meant that when I changed it , it was really dirty.

I did change it when I got it a couple months ago but not the filter . I am guilty of negligence there. so I lied when I said it had been a a while. actually more like 3000 miles ago.

that is why I am unsure why it is so dirty. I guess I need to do a good flush and refill with good stuff..


flushing out the motor worries me for some reason. what should I use? SEAFOAM maybe??

hope that clears up some facts I left out. my bad. I really do take good care of my vehicles.

It's not a good idea to thin your oil with any cleaning agents or solvents, IMO...The rotor & main bearings have such small clearances as it is with the e-shaft, any foreign substances that offer no lubrication properties might cause unwanted friction & contact at these points...Think of rubbing your fingers together with normal motor oil, then rubbing them together with something akin to MMO. Feel the difference?

You don't pour in engine cleaner and drive. You let it idle a few minutes to dissolve the crud . Then , you drain and fill it with oil. Since there will still be some solvent in the engine (all the oil does not drain out), fill it with oil and drive a few blocks to get it to normal temp and drain. Now fill with oil and you're set.
If you regularly change your oil , you don't need to do this. I change oil every month.
Also, use proper viscosity for the apropriate weather.

well.... find other threads in the forum about cleaning.....
i did the "engine cleaners" in my old celica.... i mean, that car was OLD 200k and it DID help quite a bit....

but call me a rotary weirdo, but i will never put engine cleaners (those engine restorers... blah blah) into my 7.....

oh and always change oil filter when changing oil (maybe the oil was dirty cuz of the "FILTER" was dirty)

You like making me spend money don't you? :)

because I dont know about the cars pst maintenance I am seriously considering flushing it to be safe.

I just changed the oil but have a new K&N oil filter to put on it so I might as well clean the motor first before I install the expensive filter.

Might as well. Just make sure you do it right. Don't drain all the oil then run it for a while or something to "clean it".

Excessively dirty engine oil can only mean excessive blow-by or burning oil.
Excessive blow-by can be caused by a lot of things, and fixes are expensive (i.e. rebuild) - try doing a compression test.
I hope you're not using crappy oil; if you're using a good quality brand-name oil, this should not be a problem.
As for the oil being extra dirty, thank god it's doing it's job.
I'd rather see dirty oil come out versus clean out - this means the engine oil is doing it's job.
Keep with the religious oil changes and see if the problem clears up (pun intended) over the next several oil changes.
The engine could've been neglected by it's previous owner, and your oil changes are cleaning all the crap inside.


-Ted

Well I hope I dont need a rebuild. the motor has less than 100,000 and it is strong. even with the crap AUTO it runs good after replacing the entire exhaust and a tune-up.

I will keep an eye on the oil very closely till I have had a chance to do a mild flush and then fill up and then flush again. after that I will use either Mobile 1 or Royal Purple.

Not keen on the high cost of synthetic but if I can go further then it is almost the same difference. A 5 gallon jug of M1 cost $19, a 5 gallon jug of Castrol Dino cost $8.00.

I always ran Mobile 1 in all my cars including my 85 & 79 RX when I can afford too. every one in a while I would use reg oil.

now that I read that we ca nuse ROYAL PUrple I am going to go for it.

I have been able to tell the difference in the past with the synthetics.