I changed oil the other night and after finding a very loose oil filter I thought that the oil leak previously dripping from filter was fixed. Today I warmed up the engine more than the last few days only to find the same oil leak after the engine warmed up. I checked filter and everything looks tight. It seems oil is collecting on the top rim of the filter on the passenger side of the engine. I am unable to see a source of oil leaking above almost like its coming from the filter itself. I really think its oil cooler seals but could it be coming from filter? The mating surface bw filter gasket is really small. Any help troubleshooting is appreciated before I tackle seals.

Are you sure it is not leaking from one of the push rod seals? There are eight seals and they leak over time. The newer seals are much better than the original seals. I had mine replaced last year and it solved my leak(s)!

How can I check those? Is it something I can do with engine in car?

By the way, it only leaks when car is running

If its coming from what looks like the top of the oil filter there a few areas that it could be leaking.

1) Oil Pressure switch location
2) Oil cooler seals
3) Oil galley plugs
4) Oil filter mount
5) Oil filter seal (debris on mating surface)

There are a couple others I'm sure, but I would start by looking in these areas AFTER you clean up the block. Get it as clean as you can, run the engine until leak starts and shut it down and begin the seach.

Get some brake cleaner and spray where the leak is coming from and clean and wipe. That way you can trace the leak better.

Replacing the push rod seals involves pulling your valve cover, lifters, rods, pulling push rods tubes, cleaning everything, replace seals, and reinstall everything. You will have to have valves readjusted. This is not a simple job! There may be good discussion on a previous thread.

Without a lift, this is not a fun job!

Its so weird. I just spent half hour with it running while adjusting carbs and no leaks. I guess this is the fun of owning a 914

As far as spraying things down to clean. I was thinking of simple green all over then hitting with hose but wasn't sure I needed to be careful spraying anywhere. What's the best way to clean engine?

Didn't you have another thread for this issue?

It's either the oil pressure switch or the distributor seal.

I have replied to at least 3 threads with this issue for the last few weeks between here and the club.

as always...from my own experience...had the same situation. wish it was the oil pressure switch. it was the cooler seals.

Well it certainly is an allusive leak because it only leaks on occasion and sometimes much worse than other times. I am going to pull distributor and check the o-ring there as well before tacking oil cooler sealsl. How hard was it changing the cooler seals?

dropped the engine. after that, easy.
the best part about that was getting my cooler pressure cleaned. car's been running much cooler since. actually years now....

I did it with the engine in the car, about 3 hours. Not easy but can be done.