Boris1

Hello,
I am a new owner of a 2002 C4S and just did an oil change for the first time under my ownership. When I removed an oil filter I found a rectangular piece of RTV silicone (see picture). It is about 1.5 inch x 0.5 inch in size. I am guessing that this is the work of a sloppy mechanic and I am glad that the filter caught it instead of some small oil passage in the engine, but I was just curious if someone can identify where this silicone may have originated in the engine and what repair could have been done recently to produce this.

808Bill

I'm no expert, but I'd drop the sump, check the screen and get it all cleaned out before you have serious problems.

JohnCA58

Probably won.t find anything on the oil sump pick up tube, I suspect that the tech used silicone instead of a gasket or maybe with the gasket on the oil pump primary housing, now that alone would have me pulling the oil pan to check what else he or she could have over silicone on that engine.

Mike Murphy

Boris1

Thanks everyone for your advice. I dropped the sump and here is what I see. Looks pretty clean to me. A few small specs of something on the oil pickup, but nothing major. I am thinking of just replacing the o ring under the oil pickup and putting it back together. By any chance anyone can explain to me what these two round black pieces are and how they work? They attach at the top and bottom of the case and are there any o-rings under them that may be worth changing since I am here already?

808Bill

Is that red rtv gasket material on the screen? Hard for my old eyes to see, and I'm a little color blind...

Kris Murphy

Those black tubes are the oil return swirl pots. They return the oil back to the sump. They are supposed to help make sure the oil is not aerated. There are many threads about if they actually do their intended purpose (other than returning the oil). The design was changed for the 997 to remove the swirl pots. It is a common upgrade to replace the 996 parts with the 997 parts, especially if you are installing a deeper/better baffled sump pan.

Boris1

808 Bill: No, it is definitely grey in color. I think I figured out where it may be from. Looking at it closer, the outside has a perfect edge all around while the inside is wavy. That implies that this silicone was used on a rectangular orifice and too much silicone was added and this piece squeezed out into the passageway and then broke off at some point in the future. Therefore it hardened with perfect outside edge. I was looking at a bunch of pictures on the internet as I try to learn more about this motor and I think that I figured it out. See the port in the red oval below. I believe that this is part of the oil flow from the oil pump and visually looks approximately the right shape and size. My guess is that the mechanic that worked on the motor before used silicone in this spot and put too much (I don't think that silicone is necessary at all, but that is pointless now), which then broke off. My understanding is that the oil flows to the oil filter from this passage, so hopefully the silicone didn't get any further. I am open to other suggestions and potential reasons of why this water manifold was removed in the first place.



Kris Murphy. Thanks a lot of your reply. Are there any moving parts in there? I found that there is an o-ring for each oil separator on the end of the thing tube. Any idea why it needs an o-ring, since any small leakage would just go right into the pan.

808Bill

Good find. I'm more color blind than I thought...

dporto

An internal oil leak isn't an "oil leak" per se' (like an external leak that makes a mess, and you lose oil). Instead, it's a "pressure leak" where the problem is that the oil isn't going where it's supposed to go...

Charles Navarro

Was the engine rebuilt?