Turbo smoking ??
 

My S5T2 continues to smoke. I have about 5 hours on the rebuild. It smokes more after the engine warms up.
I was thinking that maybe the smoke was coming from the Turbo. There are small droplets of oil coming out of the exhaust. After it idles for like 15 minutes you can see oil splatter on the floor and if I hold a piece of white paper up to the exhaust oil splatter can be seen in just a minute.
Ideas?

I had a smoking issue from the S5 turbo that I use on my S4 car. I found that the turbo was leaking oil from the oil drain tube (bottom) on the turbo. I removed the tube and made all new gaskets for all oil associated lines to and from the turbo... No more smoking. It was particularly a pain in the ass to install the gasket on bottom of the CHRA.

The best thing to do is clean up and degrease all of the oil. This way you can pin-point your exact leak.

Perhaps the piston ring hasnt seated, or it has failed. If the oil is getting inside the exhaust I doubt its the drain or the feed line. I had a blown turbo, and it was leaking into the turbine so severely it was leaking out onto the turbine from the inside. This led me to change the gaskets for the feed, and return, it wasnt until the seal really, 'went'. That I could tell where it was coming from for sure.

Attachment 724988

Keep in mind it was leaking like that before it started puking that much oil into the exhaust.

Also, are you sure its oil leaving the exhaust, and not fuel?

I'm pretty sure its oil. I held a piece of white paper up to the exhaust for about a minute and the paper smelled like oil. Didn't smell like gasoline at all and the smoke is thick, dense smoke not like the steamy type smoke caused by gasoline.
I don't think the smoke is coming from the engine. Extra care was taken with the rebuild to ensure everything was done correctly.

The engine is a S5 T2 but the oil metering pump is the manual type from a S4. I suppose that if the pump was injecting too much oil that would be a problem also.

Input ??

Where did you get the gaskets and did you need any special tools to replace the gaskets?

Not a gasket, it's a piston ring type seal. You can get a turbo rebuild kit from G-pop shop for $49 plus shipping. Get the Garrett T3 basic kit with the 1pc carbon encapsulated seal.

http://gpopshop.com/products-page/ga...asic-t3-kit-2/

Read this too:
https://www.rx7club.com/showthread.p...d+turbo+hybrid

I'm currently experiencing this very same problem on my new turbo (sucks). The path I'm taking is to install an oil restrictor 'pill' in the -3AN feed line. I hate to restrict the oil flow on a journal bearing turbo, but I suspect that boosting my oil pressure with a RB 85psi regulator(mistake) is the culprit Are you using the stock oil pressure regulator? Also did your rebuild your turbo?

I haven't rebuilt my turbo, just the engine and I'm using the stock oil pressure regulator..... about 65-70 psi when cold, drops to 50 ish when warm.
I don't think it would be a good idea to restrict the flow of oil to the turbo.

I'm not sure where the oil is coming from but I'm pretty sure its not coming from crankcase pressure and it shouldn't be coming from the oil control rings.
I was thinking of dropping the turbo and then fire it up to see if it smokes without the turbo in the exhaust stream.

No need to install a restrictor if the turbo is stock. The only time it becomes necessary is when someone rebuilds the turbo and removes the stock restrictor from inside the bearing housing.

I'm not sure running the car with the turbo off will be very conclusive. It'll be loud and might just smoke regardless. Usually if it's coming from the turbo, it'll leak externally like LokiRx7.1 showed. If it's leaking from the oil control rings, it'll pool up inside the exhaust manifold. It's hard to tell though, since you did just rebuild it.

Wasn't it smoking after a rebuild because of a backwards oil control ring or something?

Blown oil seal. Happend to my turbonetics and was leaking oil into the exhaust and creating lots of black smoke and the turbo itsself was smoking in the engine bay.

I'm surprised you remember that story but after disassembling the engine we found everything with the rotors as it should be. The problem then was the bad, super large primary pot job and the po left out the primary defusers and the po had the vac lines in the wrong place. I suppose that whatever was causing the smoke back then is probably causing the smoke now.
I ordered a rebuild kit for the turbo, maybe I'll get lucky.

Often I would see smoke in the engine bay but I couldn't put my finger on its exact point of origin.
Thanks for the input.

Is the stock S5 turbo the Hitachi HT18 or the Garrett t3? One link is for the HT18 and the other is for the T3.

The Hitachi Ht18 uses the same exact internals as the garrett T3. The journal bearings, piston ring seal, compressor seal, and thrust bearing are the exact same.

The HT18 kit is $89 and comes with so much extra stuff that you will not need for the rebuild.

How do your plugs look?

Did the engine smoke before the rebuild? I'm betting on the oil control rings. Either the springs were installed wrong or one of the seals was damaged during installation.

I'm not sure, I'll pop them out a check them.

It did smoke before this rebuild. That was one of the reasons we disassembled the engine. But, it was only a secondary reason.

Extra care was taken assembling the engine. The oil control rings should not be the problem. The springs definitely were not install incorrectly. As far as the oil control rings being damaged, I hope not. The rings were examined carefully before being reinstalled.

Its pretty simple to determine if its the oil control rings, or the turbo.

Im most cases the oil control rings will smoke on startup, and the smoke will taper off as the car warms up to operating temperature. I have had some really bad oil control rings, so bad they would smoke out my neighborhood, yet when it warmed up it hardly smoked at all.

The turbo worst case scenario will smoke at startup, and continue smoking even if the car warms up. It will produce more smoke when revved then idling. Sometimes the turbo wont smoke until the car reaches near operating temperature, and will then smoke until the car is shut off.

Pull the plugs, are they wet? If they are wet and oily then the oil control rings are likely the culprit. Pull the turbo, and the exhaust manifold. How do the exhaust ports look? If they are oily, then it is the oil control rings. If they are dry however, that doesnt completely rule out them out. Check the exhaust manifold, is the engine side dry? Does it look like the turbo has been leaking oil down into it? This simple diagnosis will point you in the direction of your problem. Keep in mind, parts can fail a hundred different ways, so this method is not foolproof.

I find the easiest thing to do is to pickup a spare known good turbo to have around. HT-18's can be had cheaply these days, so its worth having an extra or two. Then you could switch turbos and see if the problem persists. Although if your exhaust is loaded full of oil from a previously bad component, it can still smoke even with good parts.