Used ACDelco PF-25 Oil Filter Cut Open

Inspecting the inside of a used oil filter can tell you if something is wrong with the wear and tear of your Corvette's engine, and even though I was not expecting any unpleasant surprises, my anxiety level jumped a point or two as I removed the paper element out of the casing.

Fortunately, any worries were soon put to rest as the paper element, other than showing normal signs of wear, did not reveal any metal particles.

So all is well with my engine!

Taking an oil filter apart is not difficult, as long as you have the right tools. In my case, all that was required was my Dremel tool with a cutting disc. I did not want to break out the big grinder since I did not want to run the risk of introducing metal filings to the filter which would have negated my inspection.

You will also need eye protection, gloves (I used nitrile gloves), and a respirator.

As the video at the end shows in great detail, I cut the outer shell using the top rolled edge as a guide. This worked well as it allowed me to cut a fairly straight line which, in turn, allowed me to repurpose the cup.

Once the outer shell was out of the way, the next step was to remove the paper element from the assembly. 

Easier said than done.

The paper element is glued between two metal plates and they did not skimp on the glue. Also worth noting is the fact that the paper element is made out of a heavy grade of paper resulting in a pleated piece measuring 82.5 inches long.

Yes, almost 7 feet!

Once that paper is folded down to size, it provides a pretty solid glue surface which makes removal quite challenging as shown in the video.



The photo above shows the inner assembly with the filter removed. You can see the perforated oil return tube in the middle.

These filters, by the way, hold about a quart of motor oil in them, and I always fill them up before installing a new one since I feel doing so helps the new oil circulate faster. Very few mechanics bother to do that so that's another good reason to do your own oil changes.


By the way, the motor oil in the oil pan, pressurized by the oil pump, enters the oil filter via the five openings shown by the red arrows above, then it's pushed through the paper element pleats which filters it, reentering the engine block through the center duct (green arrow) eventually returning to the oil pan where the process starts all over again.

After spending about an hour taking the old filter apart, I was left with the outer shell, which gave me the idea that it would work great as a pencil or small tool cup.

So I gave it a good cleaning and filed the jagged edge.

I used a piece of 1/4-inch thin rubber hose I had to give the open edge a more finished look. And I have to say that it turned out pretty nice.

I think it's great to repurpose old automotive parts instead of throwing them away. 

As someone once said, "You can't throw it away. Such a place does not exist."


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