What wears out or why does an older engine's oil get dirty quicker than a new/rebuilt engine?

 

It could be old oil residue left in the motor

 

Worns seals allowing increased blow-by from combustion...


-Ted

 

Lack of proper maintenance

 

Have faithfully changed oil/filter (Mazda filter) every 1,500 miles. Hard to see the level on the dip stick it is so clear.

And yes it is over kill. Got 228,000 on first 7 changing every 3,000. So for the few buck extra maybe this one will set a record for miles on original engine.

 

Lack of proper maintenance? I do not think so. Oil gets dirty. It is the reason engines use oil. Engines use oil for cooling, lubrication, corrosion protection, and cleaning.

I probably forgot some of the uses of oil. Oil gets dirty. That is a simple fact. That is why it is there. That is why we change it. Combustion is a dirty process. And oil is there to help keep it clean.

 

and if oil is so clear on the dipstick, well, lets just hope thats a metaphor. and by the way, i believe mazda oil filters are now ford oil filters. you can still get nippon denso, though.

 

I don't understand why people want the oil to STAY clean???
If the oil is dirty, then it's doing it's job!&nbsp Dirty oils shows that the oil is pulling dirt and crud out of the engine!&nbsp The faster the oil gets dirty, the better the oil is doing it's job.&nbsp I would worry about oils that stay clean the whole time.



-Ted

 

Is it not safe to assume that dirty oil is dirty due to denatured oil by products and additives, foreign material, that heat to some extent breaks down the oil, and that crud in the oil means this crud will carbon up more readily than clean oil? Maybe we can extend that to suggest that seals exposed to combusted dirty oil will not live as long as those living a clean life?

 

I'm assuming we're talking about good, quality brands - not the off-brand stuff that sells for cheap.


-Ted

 

I believe changing the filter is more important than changing the oil. From now on, i'll be replacing my oil filter two times for every oil change (3,000).

There's only so much crud that the oil can soak up before it changes the consistency, viscosity, and texture of the oil.

 

Uh, ok...


-Ted

 

Your the man. I love that no nonsense way. I may not agree with everything you say, but you do use common sense. I like that!

 

I used to know a guy who used do this everytime he changed his oil.

1) Empty oil oil out.
2) Fill with 5 new quarts of oil.
3) Run engine for 5 minutes.
4) DUMP oil out.
5) Remove oil filter and replace.
6) Fill with 5 new quarts of oil.
7) Run engine for 5 minutes.
8) DUMP oil out.
9) Refill with 5 new quarts of oil
10) DONE.

The logic was that the first "flush" got rid of the old oil. The second flush was for the new oil filter.

Go figure...


-Ted

 

That such a waste of a deminishing resource. Even I have my limits. That's just plain wasteful. Not to mention moronic. hahaha