Hello All, Looking for some advice and perhaps confirmation to what an New OEM 350Z - VQ35DE Upper Oil Pan is supposed to look like. We received a brand new OE upper oil pan from Z1 and installed the part following following the procedure from the OE Manual. Including installing the pressed in check valve within the oil filter housing. When we started the car we noticed oil pouring out of an empty port next to the oil pressure sensor. After some research that shows what appears to be a ball that is normally pressed into this empty port, and it is my understanding that this is meant to be sealed from the factory with an interference fit ball pressed in to seal the hole that was created in order to machine in the oil passageways.

We went back to Z1 and first they sent us part numbers for a bolt, that we were meant to transfer over; there is no bolt, nor threads in this port, so I believe they misunderstood where exactly this was. Now they are saying that no new oil pans come from the factory with that sealed and that they have supposedly checked their existing stock and none of their oil pans come with this port sealed. They also say they can't find an OE part number for what is supposed to go there, so they can't help us.... So my questions to the group, are as follows.

1. Is Z1 correct when they say that new OE oil pans do not come with this part sealed and it requires modification (tapping and installing a bolt, or pressing something else in to seal it) in order to install this brand new OE component and have it function without pouring oil everywhere.
2. If my assumption is correct and they are not correct, how would you go about convincing Z1 that they are wrong and to either send us the correct part, or refund us? They keep coming back to the - there is no OE part number or reference in part diagrams to a part that would go there.




Oil Pressure sensor and empty port

Zoomed in empty port



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Link to another post that shows this part as I understand it is meant to be from the factory https://my350z.com/forum/maintenance...leak-help.html

 

Just my 2c...

It's possible Z1 is telling the truth on this matter. It depends on who their supplier of the upper pan is. It's also possible that the mfg. stopped installing the ball bearing seal as a cost cutting measure. This is not all that uncommon to see on many Nissan vehicles. I would just install the ball bearing, it's a simple press fit. It sucks that this was not disclosed by Z1, it should be mentioned in the item description.
-Icer

 

For clarification, I just got an upper pan, from Z1 and that hole is plugged. Do what you will with that information.