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Engine oil pooling between filter cap and oil cooler
I’m gonna have to change the gasket on the oil cooler, maybe the gasket on the filter housing even, would worn cap gasket also contribute to this leak, doesn’t look bad? Most oil is in that cavity between the cap and top of cooler.
2014 GLK350 base model (active) ; 2001 E320 base (retired); 2001 Wrangler soft-top
I had this same issue a while ago.
Turns out it was the outer o-ring that is around the oil filter housing ... and BE SURE the filter housing is tightened to the correct torque.
I'm NOT saying that my solution will fix your leak, but it's a fast and inexpensive "test" to see if it's the solution.
(i.e., just go to the local auto parts and buy a new filter, to include the o-rings).
For me, you could actually see the oil sputtering out (slightly) while the engine was running, although it was leaking out the backside, so was difficult to see (initially).
I even posted my problem and the solution out here.
New oil filters come with new O-rings, for the cap and the inner plastic stem.
Based on the pic, it looks like your cap is not screwed on all the way; I can see the rubber O-ring around the base of the cap. The plastic lip of the cap should be touching the oil filter housing; perhaps that's why yours is leaking?
Yikes yes get that corrected soon, thankfully you kept an eye on it, some people weren't so lucky with a seized engine because they put the o-ring in the wrong slot.
Thanks for the replies guys, I got some time to look at it again, looks like the o ring is still in the right place, was torqued down to 25nm, maybe a bad ring? leak was only on the right side close to the cooler, Ive done over 30 of these oil changes on this car and nothing unusual/different that I can recall from the previous changes, same filter used too.
Thanks for the replies guys, I got some time to look at it again, looks like the o ring is still in the right place, was torqued down to 25nm, maybe a bad ring? leak was only on the right side close to the cooler, Ive done over 30 of these oil changes on this car and nothing unusual/different that I can recall from the previous changes, same filter used too.
Bad o-ring is not impossible defects can happen, just change it and monitor closely : )
looks like the o ring is still in the right place,
If you can see the o-ring it's not in the right place. The o-ring should be completely down in the housing and the flange of the cap should butt up against the top edge of the housing.
This is a generic picture, but you get the idea:
If you put the o-ring up against the flange then it will not seal properly and the oil pressure will actually force the o-ring out of the space between the cap and housing.
If you can see the o-ring it's not right. The o-ring should be completely down in the housing and the flange of the cap should butt up against the top edge of the housing.
o ring is inside when torqued down, can’t see it, just the plastic touching the top edge like you said
Are you sure that's where it's leaking from? That type of seal is extremely reliable, unless the o-ring is visibly damaged. Could it just be spilled oil from the oil change?
Are you sure that's where it's leaking from? That type of seal is extremely reliable, unless the o-ring is visibly damaged. Could it just be spilled oil from the oil change?
Unless it’s the oil from the oil cooler, was following the drip and it made its way down to the the ac compressor, I actually just noticed a split in the drive belt
2014 GLK350 base model (active) ; 2001 E320 base (retired); 2001 Wrangler soft-top
That type of seal is extremely reliable, unless the o-ring is visibly damaged.
An opinion, of course. Why? Because __I__ had the same opinion with a past experience. Experience? Yea, check the link to my past thread I posted previously in this thread
I was POSITIVE I would see visible proof of a damaged o-ring, when I removed the oil filter housing. I was sure it would be cut or torn or oddly crushed in some way ... but it was NOT.
However, it was obviously "physically" flawed. What? When I screwed down the filter housing, there was zero tension. Why? Because the o-ring was circumferentially worn, but not particularly visible.
Physically, it was immediately obvious, after the new o-ring was installed... it took noticable physical force to screw the filter housing down, at the point when the o-ring met the aluminum cover, to its final seating.
Okay, I'm not trying to convince anyone, that my problem is @SAVZ 's leak. Just another experience to offer.
Last edited by calder-cay; Jan 24, 2025 at 12:36 AM.
Why? Because the o-ring was circumferentially worn, but not particularly visible.
Was it a new o-ring? Wear doesn't make sense in a joint with no relative movement, unless it occurred during installation, in which case I'd have to call it operator error... O-rings do take a set over time, and that is the reason why they should always be replaced if disassembled.
The design of the joint is such that the pressure tends to force the o-ring into the tiny gap between the OD of the cap and the ID of the housing. Until there is a mechanical failure, it should not leak.
I changes the 2 gaskets, put in a new thermostat as the rubber in he old one was looking deformed. Waiting for a new upper radiator hose, there was a leak at the connection to the thermostat when i put in new coolant. I still had a bottle of the old blue stuff, but it's now discontinued.
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