Oxidized Oil - should I change?

[zerosoma]

Did the blotter test on paper and with water.

The blotter test on paper reveals a dark center with a distinct lighter colored outer ring.

The water test resulted in the first drop spreading immediately, and the following drops beading on the top but then spreading after a minute or two.

I'm under the impression this is oxidized oil. I'm running 3.5 qts of Quaker State Ultimate Durability and 1 qt of Quaker State Advanced Durability, my semi synthetic blend.

Time to change oil? It's been in there 4,200 miles.

 

[Quest]

When in doubt: change your oil.

blotter test is crude/meaningless and if you seriously want to do something to accurately identify it, send an oil sample to labs for used oil analysis.

Q.

 

[Rand]

send in a used oil analysis or do what makes you feel good. Blotter test is fairly meaningless for telling how your oil is doing.

Its interesting though... esp on old lawnmowers/tractors.

 

[dnewton3]

Get a used oil analysis. In the absence of that, follow the OEM OCI.
This isn't a used oil analysis; it's not even a real test.
Moving the thread.

 

[Doug Hillary]

Hi,
zerosoma - The blotter test is meangingful for those experienced in its use. In your case this is not so

It was really instigated by the Major Oil Companies many years ago primarily for use by their Representatives as a "field test" and was and still is used as such. This was/is still the case with for instance earthmoving equipment being used in remote locations.

It is useful for determining such things as fuel dilution