Oil burning issue
 

I have a fully pretty much all custom turbo set up but I have been through a turbo already and have driven the car max of 50 miles. I went with the cxracing turbo from their turbo kit. I have had this issue with both turbos though where it seems that the turbo may be recieving more oil then it should and it seems that it is the cause of my oil burning issue. I'm not sure if I need to fix my oil feed and return lines or what but I would love some advice on what may fix this issue.
https://cimg1.ibsrv.net/gimg/www.mia...52e61cf65b.jpg
https://cimg1.ibsrv.net/gimg/www.mia...1bc0c3a41c.jpg
The plate that is connecting the feed line to the turbo is an oil restrictor.

What size is that return line? It looks to be a -8, or possibly even a -6. No return line should ever be smaller than a -10. And some fittings are smaller than the hose ID, so you have to check that as well.

It should be -10an for both but I'm thinking that maybe the 90° bend fitting may be causing the oil to backup. These are what I am using https://www.ebay.com/itm/36357300605...mis&media=COPY (90° fitting) and the drain line is here

https://www.ebay.com/itm/28324995737...mis&media=COPY

If it's 10 it should be okay. The problem could be the npt adapter. Those are always a restriction, right at the turbo where it matters most! The threaded fitting is just about always smaller than the id of the an.

The 90s should be no problem.

what other options are there then? What threaded fitting should I look for that wouldn't cause a retriction? If you have any suggestions that would be awesome! And of course thank you for the help, totally appreciate it I've been chasing stupid issues on this car for months now and would love to drive it before winter comes.

I'm a pinch, what I do is to weld the npt fitting to the threaded base and then drill out the restriction in the fitting.

Alternatively the are fittings such as these that work well. They cheap import ones sometimes require drilling as well to match the hose/fitting ID. When possible, I prefer the last link, which has an integrated o-ring instead of the annoying paper gasket. You can use copper rtv instead of the gasket but that's even more of a mess if you have to pull the fitting off in the future.


https://www.amazon.com/Turbo-Oil-Drain-Flange-10AN/dp/B00MEQN2RQ


https://www.amazon.com/Pulsar-Fitting-PRECISION-TURBONETICS-GARRETT/dp/B07SG495ST

https://www.mazworx.com/store/p/73-Mazworx-T3/T4/T6-Oil-Drain-Flange.aspx

Your drain fitting might be fine. It's worth checking before ordering parts. I am skeptical of them from experience.

Alright thanks! I think the plan is going to involve checking/drilling put the flange to get extra flow and probably buying new 10an line and just going directly to the fitting in the pan. Rather than messing with and bending fittings. This should narrow down my points or restriction. Hopefully 🥲

Some designs have a specific inlet orfice size for the oil feed so the turbo seals don't see too much oil and leak. Might be worth exploring this.

Worthy to note that brand new turbo and turbo parts can produce white smoke from the engine bay as packing oil and grease is burned off. My brand new turbo and turbo bits made white smoke and smelled like burning oil during the first few warmups and drives. Stopped after a handful of heat cycles

While Journal bearing turbos (I'm guessing the CXracing is JB) need more oil, and it can be OK to run "all of the pressure", I had a similar issue with a OEM nissan 2554 that was solved with a restrictor. IIRC I used a pop rivet head in the feed line for a DIY setup, after reading about that trick on the internet. Don't go too small on the restrictor or you will smoke the turbo though.