Turbo Drain Too Short?
 

Hello all!

Back to my roots of my H-T days. I'm experiencing a small oil leak from the compressor inlet side of my turbo. I just installed an OPR which really helped, but after doing a few test pulls I noticed a few drops still.

Is my oil drain too short/not tall enough to properly gravity drain (photo below)? If so, it seems like I'd need a scavenger pump set up.

Could it still be blow by, should I look to add more PCV vents?

* Fully built d16z6 (albeit a long time ago) with a base tune on a chipped ECU. Plan to dyno this fall.
*Spoolin performance turbo manifold
* New Garrett 2871R with <30 miles on it. Bought a few years ago. Only miles on it are for testing purposes.
* Just installed a ACL race oil pump. Caused a lot of oil pressure to go to turbo. Installed a TurboSmart OPR - removed restrictors and turbo steadily sees 40PSI, which is within spec.
* PCV from breather to catch can, and from block to catch can
* It took a lot of trial and error but this is the best oil drain I could make.

https://cimg1.ibsrv.net/gimg/honda-t...7302b44a03.png

Re: Turbo Drain Too Short?
 

I’m guessing the manifold is a a log type? I’m currently running a custom ram horn on mine and had a similar issue when it comes to the drain line

here are my suggestions:
1. Rotate the turbo so the oil feed and drain are as close to 12 & 6 o’clock as possible
2​​​​​. Massage the oil return fitting on the oil pan upward…using a floor jack. Raise the car and set it on jack stands. Put the floor jack at the edge of the fitting and SLOWLY raise it up.
3. I use a 60* 10AN fitting out of the turbo drain into a straight fitting at the oil pan.
4. Use the highest flow drain fitting for the turbo. If you look at the “square” opening. It is beveled to allow oil to drain smoother and easier. It comes with a rubber o-ing instead of the typical paper gasket.

https://cimg2.ibsrv.net/gimg/honda-t...a40bcde70.jpeg
https://cimg3.ibsrv.net/gimg/honda-t...8a96b49d3.jpeg

Re: Turbo Drain Too Short?
 

Spooling performance... man you are an oldie. That company was up there with AFI turbo who orginally did my kit. Still using the original unmodified manifold too lol. I can definitely see that setup having a drain problem or filling up the chra problem. That 45 degree drain fitting is the problem. I rotate it so its 12 o clock like nvturbo said. But also try to get a straight fitting

I think that setup mite be too taller for his setup. He may be able to find a 60 degree full tapered fitting thatll go right into the chra

Re: Turbo Drain Too Short?
 

A sump drain mite not be a bad idea. But youre not the first person to go thru this. Anymore pics of the angle?

Re: Turbo Drain Too Short?
 

he could probably use (2) 60* fittings along with the oil drain fitting i mentioned. Since I switched it to those, no more oil back-up. It was bad enough I had to rebuild the turbo

Re: Turbo Drain Too Short?
 

Yup! More photos below. I've even included what it looked like when I had a straight fitting on it. Take a look below - just added more shots of the journey. I thought I wasn't the first but can't find anyone who had similar issues!

Oh I've already tried these fittings + every other fitting/AN already available. Manifold is actually not a log - its a mini ram. I'll add a photo shortly.

The angle is too tight for any AN fittings which is why I switched to a hose/barb. If you take a look at the specs you'll see unfortunately there isn't enough space for anything AN. I added a photo below with an AN collar for reference which really drives home how tight it all is. Also below is what happens when I use a straight barb - the end of the barb falls below the oil line. The angle is used with a fish eye which made it seem like I had more clearance then I really did.

Every MM matters, and the only fitting that is shallow enough is a barb with a male screw end. Since its a BB turbo, I actually don't want to be at exactly 12 and 6 o'clock. I spoke w/ ATP turbo a bunch, and my current set up was the best we all could manage.

I could lower the bung, but that would mean I would need to cut some of the baffling. Anyone ever done that?


https://cimg0.ibsrv.net/gimg/honda-t...8007608f0.jpeg
https://cimg1.ibsrv.net/gimg/honda-t...75ef92ce0.jpeg
https://cimg2.ibsrv.net/gimg/honda-t...8e3292348.jpeg
Here I did a test where I wanted to see where my oil line was. This is how much oil would be in a normal D16z6, and I welded my bung in the 2" right above the baffling. I have another photo of the inside of my current pan after the bung is welded on if that helps.
https://cimg3.ibsrv.net/gimg/honda-t...0d7131ab0.jpeg
Here you can see the offset of the oil fuel feed. The manifold actually covers the oil feed, so I had to clock it and use an extender. It ended up not being a big deal because I'm still within spec of a BB turbo that is water-cooled ( up to 20 degrees clocked from straight up and down. I believe I'm at 17*) https://www.garrettmotion.com/racing...-optimization/

Re: Turbo Drain Too Short?
 

How long was your line?

Re: Turbo Drain Too Short?
 

Haha I feel like anyone with a turbo D series is an oldie! I feel like everything is K now, and I'm seeing those long blocks are as much as D series! I got it new, and like the manifold but hate these logistical problems they give me. ATP turbo greenlit the 45 degree angle - its the 90 degree angle they said was a no go (ironically it would be perfect here). Its already rotated as much as it can go, About 17* from 12/6p. BB turbos that are water cooled need to be clocked up to 20* upward, so shouldn't be exactly 12/6 o'clock. I'm at 17* which is within spec. (https://www.garrettmotion.com/racing...-optimization/)

I dropped a photo below of the straight fitting. Unfortunately, because its so tight, the bottom of the fitting falls at the oil line so there is no way to route it to the pan, above the oil line, without having a low spot.

Re: Turbo Drain Too Short?
 

Couple things. You could try using those same fitting styles but upping it to a bigger size. Which was what i did for my ramhorn years ago. Also, ive seen more recently on a members build. Where they had their drain looping down to the drain. Ill see if i can find it.

But a small fabbed sump drain off of the chra mite be practical

Edit...
https://honda-tech.com/forums/forced...3376764/page7/
@theYBLEGAL mite be able to comment on review on the process and on the results.

Re: Turbo Drain Too Short?
 

short…like no more than 6” I believe…a tad longer than yours. I was running commercial grade hose (same as those hoses at gas station pumps) for the longest time but decided to go back to 10AN lines

Did not realized your manifold lowered the turbo that low. Looks like the turbo drain is about 1” above the oil pan fitting …damn.

Re: Turbo Drain Too Short?
 

Haha its not 1" its 1.875"! Hah!

I wish I had 6 inches. I might just ask my tuner when I get a little closer on his thoughts.

I'm also in PHX, so I can call Hasport to see if Brian has any suggestions.

Re: Turbo Drain Too Short?
 

This is a great share - I may DM them to see how this worked out. @theYBLEGAL How did your turbo cool? It looks like you had a similar problem and looped it down + used a 90 degree fitting. Any oiling issues or drain issues?
https://cimg1.ibsrv.net/gimg/honda-t...b5a763cc41.jpg

Re: Turbo Drain Too Short?
 

Hey hey! Figured I'd just reply here. Well, it did work out alright enough. I didn't have any issues after multiple lap racing events with the setup running that way. Turbo is still healthy.

I might have had a small drip or two but I'd blame that on the communist AN hoses or fittings lol.

I've since re-worked it. I was able to get smaller turbo drain fittings that let me begin my slope toward the pan sooner. Seems good, less drips/no drips. Female threaded 2 bolt flange on the turbo, threaded in a hose barb to it. AN fittings were just too bulky

https://cimg9.ibsrv.net/gimg/honda-t...2fa0374d68.jpg
https://cimg0.ibsrv.net/gimg/honda-t...5008be980c.jpg

Re: Turbo Drain Too Short?
 

Damn that looks really

@everythingwentblack is your turbo drain and pan inlet inline or offset?

Re: Turbo Drain Too Short?
 

Good to know! I did something similar w/ the female flange on the turbo. How tall is your set up? It looks like you have maybe 3-4" there to work with.

Any issues w/ the 90 degree fitting into the pan? How long is your hose?

I'm just under 2" tall of height - maybe I can route the turbo hose into the pan over more for a little more hose length.


Pan inlet is straight on from the turbo! When I went to go weld on my bung I routed it straight into the pan.

Re: Turbo Drain Too Short?
 

Oh duh... totally forgot to just look at your previous pictures posted.

Are you opposed to dropping the pan and making a new bung offset enough make something similar to theyblegals drain?

Re: Turbo Drain Too Short?
 

All good!

Not opposed at all. I've got a welder and don't mind hacking up this pan until I find something that works - then redoing it nicely with a new one. From what ATP turbo tells me, this problem won't negatively impact my turbo or anything like that - and once I find a solution I don't need to pull the turbo apart either.

What I might do is ask my tuner when I get closer to being ready to make my appt - if he gives me the go ahead I might just send it and circle back to this after to fix.

I've been building this car for a while so looking forward to getting it on a dyno.

Re: Turbo Drain Too Short?
 

Thats something that could be done. If i were to go that route, id be tearing it down that very night affer the dyno tuning. That way it doesnt get put on the back burner and forgotten about

Re: Turbo Drain Too Short?
 

For sure. With cars there is plenty to do post tune so it doesn't stop there, but after all these years would be nice to see the light at the end of the tunnel and feel some semblance of success.

Re: Turbo Drain Too Short?
 

Update - I found out that my d16z6 oil pump pickup tube was too close to the oil pan.

I'm running the ACL race oil pump, and my pickup was less then 1/4" from the bottom of the pan (recommended specs have the pickup filter 1/4" - 3/8" above the oil pan). So, I'll need to swap it to a D15 pickup to fix the issue. By running the wrong pump, my oil pressure was higher then usual, which could be a contributing factor to my turbo drain issues (running the correct pickup tube may or may not solve my issues).

I'll circle back once I've got it all situated and ran the new set up.

Re: Turbo Drain Too Short?
 

So, don't try to starve your oil pump...

Try a turbosmart turbo-oil-feed regulator feeding the turbo.

Re: Turbo Drain Too Short?
 

And I thought my turbo was low! I have also struggled getting the drain line right with my "mini ram" type manifold, though mine is a b-series I still have about an inch of drop in the drain line down to the pan. That is also with a Moroso 4qt oil pan which I'm not sure, but might provide better drain back characteristics than a stock one.

I think in your scenario, an in-line scavenge pump for the drain would be the best solution. They aren't too pricey and would give solid peace of mind with your setup.

Re: Turbo Drain Too Short?
 

Re: Turbo Drain Too Short?
 

Yup! I already have one. Love it.

Yeah so drains seem to be a common issue with these style manifolds...

Another big update. Got the car dynoed and it was low on power. Ended up dropping the oil pan and found glitter! Further inspection revealed that the rod bearings showed excessive wear (it didn't spin just wore).

Pulled the entire motor out and apart - dropping it off at the machine shop tomorrow. Journals and crank bearings look great, cross hatching still good, etc. Motors got less then 100 miles on it since my initial machine shop visit where everything was blue printed, balanced, etc.

So they will clean it up, inspect and measure everything + double check all clearances with new bearings. Once I get it back, I'll begin reassembly, and take the time to upgrade some aspects of it. Going back to OEM head gasket, I'll put a new water pump on there (coolant looked gross), and they recommended I just buy a new oil pump.

I'll chalk this up to a learning lesson and shelf the ACL one, going back to OEM. I'm only going for ~350WHP so OEM should be fine for my power goals.

As far as my issues, I think two things could be the culprit. One is simply having the wrong pickup tube since my clearances were so close to the pan it led to starvation at higher RPM's and caused my motor to have excessive crankcase pressure. After the dyno I noted leaks from my turbo drain (still) + came out of my the vent of my CC. The second could be the fact that I build this motor ~13 years ago, and its been in various stages of completion until recently. Its certainly feasible that somewhere along the way, with various valve cover swaps, oil pan drops, oil changes, turbo upgrades, that something got into the system that shouldn't be there which caused some of this ruckus. In the long run I think this tear down is a good thing.

As I know more I'll circle back and update here - this is good info to memorialize for those in the same boat. I feel like D series builds are coming back baby!

Re: Turbo Drain Too Short?
 

You tried to lower oil pressure by raising your pickup tube out of the oil pan? Idk if i read that correctly but if i did thats probably why the bearings wore out