Hello All,
My 1998 Infiniti I30 with 235k miles recently started to get its first oil leak dripping to the ground. I've never replaced any gaskets/seals due to the history of no worrisome oil leaks until now. Looking around underneath, I seem to have slow leaks which aren't severe nor hitting the ground near the front main seal, rear main seal area, and lower oil pan. Rear valve covers seem to be leaking a bit too, but it's tough to tell how much. Oil pressure switch looks fine. My oil is mainly dripping in 2 areas...off the lower control arm, and from higher up somewhere in the middle between the control arm, lower oil pan, oil pressure switch harness areas. I did do a UV dye test and it looks like my oil's worst leak is onto the top/back side of the power steering pump, and also onto the power steering line which runs just to the right of the power steering line seen in the red circle below (the one I'm talking about is hidden in the image / behind the intake manifold there). I've been getting about 1-2 drops a night for a couple months; sometimes more, sometimes less. What is probably causing this leak? Rear Valve Cover, Timing Cover O-Rings or Gasket, or anything else? thanks

 

All of the above should be checked, my guess is the larger amount would be coming from the timing cover o-rings, a common leak area.

Might wanna change that control arm, or at least the bushings. The oil will break them down and cause play in the arm.

 

I looked at the control arm today and it looked OK (I replaced it last summer for the first time so it should be good to go for a while I think). As for the leak, I was hoping to not deal with the timing cover unless I knew for sure it was that...I know it's a big job. Unfortunately I can only see so much back there, even with the UV dye. But yes the bulk of the leak is falling onto the top/back of power steering pump. The dealer told me it was the front main seal but I wasn't sure about this, and the UV dye confirmed it (there's no oil showing on any pulleys/belts or either side of front crank pulley or front side of power steering pump)...he seemed to just take a quick glance at it. I appreciate it if anyone else has any history/idea what usually causes leaks in the spot I have.

 

I've got that same thing gonna on....may try it in the car...not sure yet!

 

I'll take a closer look with the dye when I have a chance...seems to be easier to see at night. As for the 2 o-rings, how exactly does the oil leak out onto/near the power steering pump if the o-rings are on the "inner" cover? And what are their main function? thanks

 

Is the timing cover O-rings area reachable from above by hand? Today after a drive and cool down I reached down about 6 inches from above behind the left side of the intake manifold to feel plenty of fresh oil back there around the timing cover/rear valve cover area. I'm assuming that if the answer to my question is no, then a new rear valve cover gasket will solve my problem. I actually felt a little gasket-like piece sticking out somewhere back there also, weird