IainM

Just changed oil and cut open filters to inspect for particles. Does the oil flow from outside to inside on the filters?

In the past I've always cut the filter paper out from the carrier to inspect both sides and found nothing but it's a PITA. If oil flows from outside to in then I don't need to inspect the inside. If anyone can confirm it would save a lot of hassle.
Cheers

phoneyman

https://rennlist.com/forums/964-foru...n-diagram.html

From looking at this post, the oil filter cap ports orientations looks like it flows from outside to inside, which is consistent with some other cars I've worked on. Hopefully someone knowledgeable will post with certainty.

bcameron59

When I opened up my filters to check for debris after top end rebuild, there were a couple of small blobs of curil-t (and thankfully nothing else) on the outside of the filter element.

Outside -> center.

But might still be a good idea to pull the filter element off and spread it out to inspect, there could be small bits hiding in the creases of the filter element.

NC TRACKRAT

IMHO, if anything, you'll see ferrous particles on the magnetic drain plug rather than in the filter. Routine oil analysis at each oil change will be more revealing than a visual inspection of the filter.

OverBoosted28

Exactly! If your inspection of particulate in the filter is your sign of problems, then it's possibly too late. Oil analysis will see things before your eyes can.

IainM

Thanks for info.

Yes, I did find v small amount of the finest iron nanoparticles on the magnetic plug. I have also been getting the oil analyzed by Blackstone since I got the car. For the price it's a no brainer.

I just keep thinking about Trophy's article.

bcameron59

Steven found the IMS fragments nowhere other than on the magnetic drain plug, so it looks like it's fairly effective at its job. But I would still check the filter element after an engine rebuild, just in case.

Otherwise for regular oil changes about all you're likely to be able to see in the filter with the naked eye are large non-magnetic bits eg if someone was silly enough to use RTV as a gasket sealant.

However the filter will still be able to catch micro particles of dirt and non-magnetic stuff that might sneak in through the air intake or oil fill cap, say if you decide to top up the oil during a sandstorm, or forget to put the air filter back in after a tune-up, or put in a kms air filter which is pretty much the same thing.

mike cap

Cutting filters open is fun and you can pretend you're Charles Lindberg's wrench on the Spirit of St Louis - oops, probably no filter on that old Wright engine, but I digress.

With oil analysis it's a total waste of time but still fun.

IainM

Well, on close inspection of the cartridge, this time I noticed the pressure relief valve on the bottom so just to confirm the correct answer, oil flows from outside to in.