Turbo oil drain options, single turbo setup
 

For my FD build, I'm bringing back the MOP and the RA MOP adapter with a gravity fed premix supply from a separate tank. Picture below pretty much sums up the interference problem I've got now with the PO's turbo oil drain plumbing that I'll need to fix. Due to the very close proximity with the MOP electrical connector/motor unit, I was thinking these were my best options for re-plumbing the oil drain:

1. Use the currently blocked off rear iron drain port instead, and put a block off plate on the front cover. I assume that rear drain port goes right to the sump as the front cover one does, correct? Then it would be pretty easy to plumb a -10 line from turbo drain to rear port with either hose or AL hard line. Kind of prefer the hard line approach as it can done in a way to better avoid heat damage from turbo or manifold. Looks like I'll be able to reuse the existing AN flange adapters on both ends either way.

2. Keep it connected at the front cover, but swap the existing AN flange adapters (the long nipple one would go on turbo, shorty on the front cover); then use a length of -10 hose with straight connectors on both ends. If I do that, it looks like I'll be able to get both fittings on, and the hose would route in a gentle arc from turbo to front cover without interfering with anything, though it would be closer than I like from some hot bits (no worse than PO's plumbing though). That's also the setup that worked for me on my FC when I had a similar problem with the MOP/RA adapter setup.

What do you guys think?


https://cimg4.ibsrv.net/gimg/www.rx7...063dd5c775.jpg

#2, put the straight bit on the engine side (if it fits) call it done

Yep, #2

#2 as well. It is shorter line and easiest to service it if need it.

Thanks guys, agree #2 is the easier approach. Also it turns out I can't swap the AN flanges from front cover to turbo sides so the longer of the two would bolt onto the turbo - bolt pattern/sizing is slightly different. Which kind of sucks as there's not enough room to connect the turbo side of the hose with the flange mounted - I have to connect the hose & flange together first, THEN bolt the flange to the turbo. If I were able to swap flanges, that would no longer be an issue. But it doesn't matter, as it will still work with the braided hose and straight AN fittings on each end. Just makes servicing more of a PITA.

Don't know if it would help any, but stock there's a steel extension that bolts to the front cover then the primary turbo oil drain connects to that. I think it's the same flange on each side of that extension. The extension is about 2-3 inches if I had to estimate.

Dale

Funny that you mention that, Dale. I am going to be using it on my next set up, but for a different reason. The ID of that extension is .58 inch as a 10 AN ID.

oil drain line
 

https://cimg6.ibsrv.net/gimg/www.rx7...b8d5294ce2.jpg
https://cimg3.ibsrv.net/gimg/www.rx7...6964d705b7.jpg

That part wasn't on my FD when I got it, but you just reminded me that I have a similar S5 FC part laying around the shop that I forgot I had! If it fits the FD front cover, it might solve the plumbing problem. The FC piece has a curve to it, so that curve might help clear the interference with the OMP.

this is where i'm stuck, the FD stuff is T2 sized and the FC is T3 sized (or maybe t3 and t4?) so the FC and FD are different diameters. however the metal is soft and i was able to swage the FD pipe larger by hammering a socket into it...

depending on the length you would need and the turbo you ll be using there is a longer version from mitsubishi evo. it doesnt work for my setup but it is a good option. i have this at home , i can take measurements if you want
https://cimg7.ibsrv.net/gimg/www.rx7...f20e9c3983.png
https://cimg6.ibsrv.net/gimg/www.rx7...858af7b2f9.png

I cut down the stock one to allow me the clearance for the RA adapter. Make sure you index it correctly to allow for the drain to be angled correctly.....
https://cimg2.ibsrv.net/gimg/www.rx7...040424624.jpeg

Well here's what I ended up with - same fittings at same locations, and about a, 11" run of hose with a straight fitting on each end. Straight down gentle arc into the pan/sump, so it should drain well enough - this is very similar to what I have on my FC, except that one is a little longer as the FC's turbo drain is closer to the center plate than the front.


https://cimg7.ibsrv.net/gimg/www.rx7...3ad481ff2a.jpg

Had the exact same issue, made a AN fitting, but there are too many clearance issues, so TIGed up a SS "long throw" adaptor...There is a specific reason not to route back to the rear, but it escapes me what the specifics were. It could even be simply tidiness...

I went with the tubing because of presumed Diameter of throughput, but that didn't seem to help what I thought was back pressure issues.


https://cimg5.ibsrv.net/gimg/www.rx7...09c3ca8e1d.jpg
https://cimg6.ibsrv.net/gimg/www.rx7...94439f11c8.jpg

What are people using for an supplementary oil retention tank typically?

As well as monitoring oil level?

For an oil tank, I'm using one of these from US Plastics - https://www.usplastic.com/catalog/it...4889&catid=934

These tanks come in a variety of sizes, and all have a 1/4" nipple on the bottom to attach a hose to. The tanks are a translucent plastic which is compatible with premix lube, so it's easy to visually check the level whenever you pop the hood open, which is why I didn't bother with a level sensor. For my FC, I got a 2 quart tank and mounted it where the air pump used to be on the 13BT. It's been in use since ~2014 with no issues. A little less space to work with in the FD, so I picked up a smaller 1 quart tank that will be going where the ABS pump was.