Burning rear turbo bearing (hot side)
 

Hmm.. I seem to be having an issue where I'm doing some not-so good things to the turbo bearing on the hot side.
Last 2 bearings, the oil has seemed to be dark on that bearing.
I'm running an oil feed from a stock turbo feed port on my block to a 6an line. That goes into a very large filter, and outputs to a 4an line to the turbo.
No restrictors in the line. Oil flow during cranking looks good, fills a 1/4 quart very quickly.
I just went to a t3 .60/.63 water cooled garret turbo. After about 180 miles, it feels like it's starting to get loose again. I'm going to open it up and look at the bearings, but I suspect it's the same hot side bearing failure.

EGTs under control.. 1350 peak, 950 cruise. Measured immediately after #4 exhaust port.

Oil pressure reads good, 25psi idle to 70psi running. This isn't measured at the turbo, but at the standard oil port on the other side of the block.

To debug oil problems - and I'm assuming this is still an oil problem - what do you guys recommend? Perhaps an in-line pressure gauge at the turbo feed?

Re: Burning rear turbo bearing (hot side)
 

We've seen -4an still manage to be pretty big and recommend a 1/16" restrictor for the feed. I would check your oil dump and see if it is nice and flowing not to mention within 30* of vertical. Also, your EGT probe should be on the THIRD runner not 4th.


JP

Re: Burning rear turbo bearing (hot side)
 

Big is the idea. Why are you recommending restricting the line if I'm burning /coking that rear bearing?


Oil dump is 1/2" ID, vertical, I can stick something under it, but it's positioned very well and has no sharp bends.

This is a 22RE, inline 4. #4 is where I'd expect the highest temp to be.

http://lakebox.dnsalias.com/photos/1.../t3-60eng3.jpg

http://lakebox.dnsalias.com/photos/1...urborebld1.jpg

Re: Burning rear turbo bearing (hot side)
 

Re: Burning rear turbo bearing (hot side)
 

Better than the last one.... The question(s) still stand, however..

Re: Burning rear turbo bearing (hot side)
 

yeah, but you aren't the only one with a new manifold!

all i can think of is, your block doesnt have enough feed to get to the turbo. tee off of the sending unit hole, plug oem turbo feed

Re: Burning rear turbo bearing (hot side)
 

New manifold? I've only had one!
On your manifold, my only conern would be clearance with the stock distributor and power steering assembly if you still have one...

I've thought about doing what you suggest... A lack of oil flow would do it... Was wondering if oil pressure can and should be measured at the turbo itself?

Re: Burning rear turbo bearing (hot side)
 

no PS so im good, you could always switch the pressure sensor with the oem feed, and just lube it from sensor feed.

doesn't matter if you have 1500psi getting to the turbo, if you can't flow anything more than a few drops, which that big filter looks to be hogging any volume that you're getting across the line

Re: Burning rear turbo bearing (hot side)
 

I'm an idiot, that's why. I don't know WHY you have a inline filter, but I'm agreeing with c0mpl3x and that could be holding things back a little bit. Then again you said it filled a container rather quickly so I'm not quite sure.


I have a question for you. Pics of your oil dump off of your turbo. Just curious on how you ran that on account of it appears you made your very on oil lines and I want to see how you mounted it on the turbo itself.


Sorry I couldn't be too much help and I apologize for the previous n00b answer; HOWEVER, common runner is #3 for an EGT probe this I'm sure of (atleast for Honda exhaust manifolds). Don't know HOW big of a difference it will make (probably minimal) in the overall case of things and your max temp is far from severe.


JP

Re: Burning rear turbo bearing (hot side)
 

I'm running an inline filter because I've got a new motor. New motors tend to generate very fine debris. Fine debris + 100k rpm of a turbo = bad mojo. The inline filter is huge, it's the size of the oil filter for the engine. 3/8 inlet / outlet.
I had these issues before I had a large inline filter also.


If you mean the oil drain, it's pretty basic. I've got a fitting that works with the garrett center section going to a piece of brass plumbing pipe. The pipe is about 4-5" long, then goes to a high temp silicone hose that was designed for oil/fuel.

http://lakebox.dnsalias.com/photos/1...urborbld11.jpg
http://lakebox.dnsalias.com/photos/1...urborebld1.jpg



I had issues with high EGTs to start with, I figured conservative timing was good.. wrong.. conservative timing = high EGTs.
I don't think it matters if the probe is on #3 or #4.

I'm still hunting as to why I'm burning turbo bearings.. I'm probably going to put a mechanical oil pressure gauge on that inlet and see what happens.