Blow through turbo, replaced seals, still oil in exhaust...

[mmason2005]

Have a 1915 blow through motor with a garrett t3/t4 set up. Rebuilt and prettied it up buggy over the winter, did not mess with internal engine but did take turbo off, send the housings off to get them ceramic coated, then put back together. Had no problem last year with blowing smoke, oil getting into exhaust, etc. Put it back together, cranked it up and it was blowing oil droplets out all over the place and blowing smoke everywhere.

Got a turbo rebuild kit, replaced seals and bearings, etc. Cranked it up, no more oil blowing out of motor, no more smoking, UNTIL it gets hot and then it only smokes at idle, or low RPMs (0-1.75k). This is like mosquito fogger level smoke, leaves a cloud, until I back on it and get down the road over 2k RPMS, it stops again. Run my finger along the inside of the tailpipe after turn it off and it cools, and have liquid black oil on my finger. When I first crank it up and it is cool, no smoking.

Inside of turbo looked good, no play in shaft when replaced seals and bearings. Not sure what is wrong here. Never had a problem last year. Drain tube is straight and above oil sump level. Maybe about a 1/4" inlet tube and 1/2" outlet. I do have a T in my outlet tube where a temperature gauge sensor is screwed in, but do not think this would affect it.

PLEASE HELP. Spent a lot of money working on this over winter, and am ready to ride! Buggy show coming up in a couple of weeks. Thanks in advance!!!

[Clonebug]

Oil is thicker when it is cold which could be why it isn't coming out.

Depending on your oil system or pump you could be pushing too much oil into the turbo.
Easiest test would be to install a 3/16ths feed line instead of 1/4 inch.
Another test is to pull the drain line off when engine is warm. Start it up and see how much oil comes out of the drain.
It should only be a little bit since turbos don't need a lot of oil. If you have a lot of oil coming out you need a bigger drain or a smaller feed.
If it's not that then the coating could have damaged something or you didn't get the seal installed correctly.

How did you keep the turbo balanced if you took it apart??? Did you index the impellers to the shaft?

Turbos are a precision balanced unit since they spin up to 180,000 rpm.

Post a good pic of the turbo install with the feed and drain lines....someone can then make an informed judgement and possibly see something.

[Piledriver]

Do you have lots of blowby/case pressure?
Could make a drainback issue worse.

[mmason2005]

Would it make sense with having the same inlet and outlet size as before I got it ceramic coated that now it is causing problems, and before it wasn't? I measured outside to outside diameter of inlet and it measures 3/16" outside diameter. Outlet (drain tube) measures 5/8" outside diameter (see last photo).

Here is photo of inlet (feed):
http://i760.photobucket.com/albums/xx24 ... 719196.jpg

Here is photo of outlet at T where I have temp gauge. Temp gauge is plumbed in facing towards the ground, to ensure oil gets on the sensor:
http://i760.photobucket.com/albums/xx24 ... 731843.jpg

Some more photos of outlet (drain tube):
http://i760.photobucket.com/albums/xx24 ... 919997.jpg

http://i760.photobucket.com/albums/xx24 ... 221529.jpg

We did not rebalance turbo wheel when installing rebuild kit. I watched Youtube video, I understand that some people rebalance and that it is recommended, but guy in video did not rebalance and I did not either. Would not balancing it cause the oil to blowby for some reason?

[mmason2005]

Okay, here is outlet drain tube with hose pulled off:

http://i760.photobucket.com/albums/xx24 ... 534635.jpg

Here it is measured, you can see about 1/4" opening. When people refer to the size drain tube you need, do they measure hose thickness, or outlet size?:

http://i760.photobucket.com/albums/xx24 ... 508882.jpg

Here is a video of my wife attempting to start the image while I catch oil that flows out. I realized I goofed and forgot to put the distributor cap back on before she cranked it, so that is why it did not fire. You can see plenty of oil coming out. though.

https://www.youtube.com/watch?v=l4ZjvxkoJkA

[andy198712]

Oil left in the exhaust maybe?

[mmason2005]

Yes, oil in exhaust. That is the problem I am having.

[andy198712]

as in, left over from when it leaked before and now its just burning off?

[Clonebug]

I said it in your first thread and I'll say it again.

Drain too small.
Feed too big...

Your drain looks like a 3/8ths line if that. Size is measured from the inside diameter not the outside.

Those fuel pump drains come with a 3/8ths NPT hole in there if that. You need to increase it to a minimum 1/2 NPT if not 5/8ths NPT.
Get rid of that temp sensor also. It is a restriction in the drain.
Oil feed needs to be 3/16ths or AN-3. You have too much oil coming out of the drain at idle.... and that is with cold oil...imagine how much comes out when hot and thin and at high rpm.
Get a fitting that fits the turbo drain hole and try to use a 45 instead of a ninety. Look at that youtube video once more and notice the drain size.......that's the only thing you could learn from that.

As far as the youtube video.......the guy is a hack and doesn't know his As* from a hole in the ground.
"Doesn't care about the wear on the shaft"?????
You probably put that turbo out of balance now and it will self destruct from vibration. Watch it closely to see if the wheels contact the housing and send bits of aluminum into your engine at high velocity.

[mmason2005]

Andy, too much in there for that, and it is more each time I run it so it isnt just residual, thanks for asking though.

Clonebug, thank you very much for your assistance. I will take your advice, and going to get a bigger drain tube and fittings.

[Clonebug]

Just checking to see how it's going on the turbo.......

Did you get anything figured out???

I found a pic of my drain compared to my oil filter lines so you can compare it to your drain line.

The blue lines are 1/2 inch Push-loc for the oil filter.
The gray line is the 5/8ths drain line for the turbo.

Look how much bigger the gray line is.



I found one pic of an overall view of your rail and it seems the drain hole into the fuel pump is too small also.
If you can weld, it might make more sense and give you a straighter path if you weld a 1/2 inch NPT bung onto your #1/2 valve cover and drain into that for an easier path than go over and around the alternator.

I put one in my valve cover for a breather drain but have since eliminated the breather since I found the blow-by problem.
Here is a 1/2 inch NPT bung installed in the valve cover.



I can pretty well guarantee that if you put in a 5/8ths drain all your oil problems will be gone.

[mmason2005]

Clonebug, sorry for delay. I went with your advice, biggest I could tap without risking running out of metal in my bottom plate on turbo was 1/2" npt. I also tapped out plate entrance going into block to open up the flow. I replaced all fittings and hoses with corresponding 1/2 sizes. This has appeared to fix the problem after driving it a few times and getting it good and hot. This completes my rebuild issues, now I ready for the buggy show this weekend!

Also, the picture you saw must have been an old picture of the buggy, during rebuild I got some different valve covers and now have a breather drain hooked to valve cover. I will have to put up some pics, but that brings up another question, how can I embed photos like you did?

Thanks again for your help!!

[Clonebug]

Upload to Photobucket at 800X600 max size then copy and pate the [IMG] url into the thread and you are good to go.