Engine contaminated during oil filter replacement

Joined
Jun 5, 2003
Messages
32,030
Location
Apple Valley, California
Whenever I change this style of filter the old dirty oil that's sitting in the housing runs down the clean side hole and right to the bearings and what not.

There's no way to avoid it. Seems like it's a way to purposely cause wear to me.

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If you wanna do a complete job, remove the oil pan every oil change. Put it on the "it is what it is" list and work other problems.
 
Isn't that the same oil that was lubricating the engine, until it was shut off to change the oil?
Yes but when i remove the filter the unfiltered oil runs down the dirty side of the filter and right down the oil where the clean oil goes.

I'm assuming that when it runs down the dirty side of the filter it could wash some contaminate off the filter and take it into the clean side.
 
I've had two vehicles with the top mounted cartridge style oil filters. I still have one of them. I have never worried about a little oil left in there. It's already been filtered and it will mix with the new oil.
I always make sure that the surrounding outside surfaces are clean before removing and replacing the filter.
 
Whenever I change this style of filter the old dirty oil that's sitting in the housing runs down the clean side hole and right to the bearings and what not.

There's no way to avoid it. Seems like it's a way to purposely cause wear to me.

View attachment 316374
Looks like there is a "wall" around the port where the filtered oil travels to the oiling system, so any left over debris that has settled at the bottom of the filter housing wouldn't go down that hole. And it's slightly tilted in this case, and any settled debris is probably on the bottom side where the oil is pooled in this case. I'd be careful cleaning out the housing in case there is any debris in the bottom.
 
Mercedes pumps oil from the pan through the bearings then through the filter. That foul oil will get filtered next go around. Consider it a bypass system.
That sounds like a genius oiling system, lol. Got a schematic?
 
It's similar to the canister filters on my old jeeps. I use a turkey baster to transfer it to a coffee can, and then a new, clean rag to wipe out that little bit at the bottom. In the old style canesters there's actually a drain at the bottom, but removing or opening it just makes a bigger mess in a crowded engine bay than it's worth.
 
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