Greetings all! I appreciate the opportunity to be a part of your group. I'm currently on my 3rd 350Z (01, 05 and now 07), All were bought new and I have enjoyed them all! I think the 07 styling is by far the best Nissan did with the Z, The "roman" nose sets it above the crowd, Sometimes folks ask what an old geezer like me is doing in such a cool car,,,, I always get looks and comments! So, my 07 has served me well for 190K miles but I'm now having oil pressure issues. When the engine is warmed up, if I let it idle down, the oil pressure drops to zero. I don't want to spin a bearing. Anyway, I've decided to try to get a new (replacement) engine in the old girl but I'm running into a stone wall. Seems no one makes a remanufactured engine so I'm looking at a "low mileage" used engine. I spoke with JDM in NJ and they have one or two VQ35HR engines. I'm in Hershey PA so the logistics will be challenging ay best. SO....I'm wondering if anyone has advice or suggestions. Has anyone dealt with JDM? Anyone know of a garage in central PA who would do the swap for me? I would have done it myself in my younger days but... they're long gone. Sorry for the epistle, any advice would be greatly appreciated.

 

Hello and welcome to the forum!

Since you have an HR equipped Z, I suspect you're experiencing an oil gallery gasket failure (Common on VQ35HR and VQ37HRs). I don't think your engine is toast, but if you keep driving it like that, then you can cause premature wear/failure of top end components (based on what I've read about the issue). Before going in on a used replacement, I suggest looking up "oil gallery gasket replacement vq35hr". If it were mine, I would do the job myself. In your situation, I recommend getting a reputable shop handle the work since the process goes fairly deep (opening up the timing case). With the mileage you have, I would honestly do a full timing set replacement and tackle the water pump while in there. It's not going to be cheap, but might end up being cheaper vs. replacing the entire engine once parts + labor are factored in.

It's your call at the end of the day. Note: This assumes your engine is healthy, meaning good compression, not burning oil, etc...only the oil pressure is low.
Good Luck!
-Icer

 

Thanks!! That’s just the kind of information I was looking for. Do you know if that gasket / seal is “testable “?
I’ll follow up. I found a couple of Utube strings.

 

The OEM Nissan gasket that fails is made out of paper. The typical mode of failure is that it blows out into the timing case, and ends up sinking to the bottom of the oil pan or getting bits lodged in the pickup tube screen. In short, the best test would be a visual inspection of your sump/pan to confirm bits of the gasket are present, but even then, this is not very scientific. Gasket bits could be stuck elsewhere in the timing case, either way if the repair is done, the lower pan needs to be pulled to make sure the oil pickup tube is clear of obstructions. There is an updated replacement gasket that's made out of better material (coated metal I think?).

I haven't seen any unique method of taking pressure measurements to confirm/verify a failed gasket. It's simply a very common failure & root cause for the oil pressure gauge to read dangerously low on these engines. Yes, the gauge sending unit could be faulty and to rule that out, you can use an analog oil pressure gauge to verify it's not a bad reading from the sending unit. But ultimately, this is a known issue on these. I have not seen any other cause or report of low oil pressure on these engines but a failed gasket. (Oh and except of course those who experience catastrophic failure from boosted mods...a.k.a. yeeting a rod out the side of the block).

Here's a link to a good thread detailing the parts required for the job.

Cheers!
-Icer