Oil causing turbo failure??

[ddavisaf]

When I first bought my Talon I had the stock T-25. I ran Valvoline 5w30 something or another.
I upgarded to a new oil blend that was supposed to be great for my car via a local mechanic. It's 5w40 semi syn. Car ran great when I first put the oil in.
Then the T-25 went bad on me.
Upgraded to a 14b. Lasted a week.
Put another 14b on. Lasted 10 miles.
So I went and bought a Forced Performance 18G Chra. Last night it went bad on me. Hit full boost a couple of times and then during normal driving I hear the signature blades on the housing sound. Drop the intake pipe, check for shaft play, no in and out, but plenty of side to side. Shaft still spins freely.
There is always warm up and cool down time. Even at gas stations when I'm just quickly filling up.

Could my oil not be causing enough cool down/lubrication?
Oil Pressure gauge reads about 10-12 psi at idle, when in gear (automatic) 8-9 psi. During driving it's normal psi levels.
T-25-15 psi
14b-15psi
14b-13psi
18G-13psi

 

[danny_l_2005]

I would just stick with 10w30 thats what mostly everyone uses, even the service manual says to use 10w30. Did you prime the turbo when you swapped them? I think you should check for boost leaks just in case. Well my 14b i put recently puts out 8psi on stock boost.

 

[ddavisaf]

Primed all the turbos. No boost leaks. The bearings keep going out on me.

 

[oldman]

I suspect this is either a "too much" or "too little" oil problem unless you truly have huge boost leaks which I doubt considering the amount of boost leak test advice you have been giving.. Check oil pressure, oil feed, oil return...etc. I think problem is there some where. BTW are coolant lines still hooked up?

 

[ddavisaf]

No water lines, it's a dry cast turbo. I have a *small* oil return leak. The gasket went bad on me, haven't gotten to change them out yet. Was waiting for the next oil change. Oil feed is a SS line from the filter housing. Oil Pressure gauge is a mechanical gauge. At idle in Neutral or Park it says I'm running 10-12 psi. In Drive is says I'm around 8-9 psi. During driving, oil pressure is perfect. Yeah, if I have a boost leak, I'd be surprised
I haven't found one, and I hold steady at 13 psi at WOT in every gear.

I can't see my oil pump being bad, but it's almost worth replacing just to make sure. 4 turbos is 3 months is kinda ridiculous.

 

[ddavisaf]

Update:
I took the turbo off and did a cold crank (no spark or fuel) to see if I was getting plenty of oil pressure through the oil feed line. Blocked off all the open oil passages. Oil was free flowing from the feed line. This would lead me to suspect the oil passages in the turbo were clogged.

I ran some brake cleaner through the oil return, there was no restriction what-so-ever.

I then ran some brake clean through the oil passages in the turbo. Used my SS fitting and sealed it off with rtv around brake clean "jet nozzle". Nothing would flow through the turbo, it would just blow the nozzle off my can. Did the same test through the oil return also, and there was no flow out of the oil feed opening. This was also done to clean out the turbo so that it wouldn't soil the box and cause delays in shipping to FP.

My question: Since I could not get any fluid through the feed, would this mean that there is a blockage inside the turbo housing? Or is this test totally inaccurate?

 

[Defiant]

Sounds like running that spool without water coked up enough oil to block supply to the bearing.

Why no water? What is a "dry cast" turbo?

 

[ddavisaf]

Sounds like running that spool without water coked up enough oil to block supply to the bearing.

Why no water? What is a "dry cast" turbo?

It's the way it was made. By dry cast I mean no water lines were cast into the center section of the turbo.

 

[scottsee]

kinda sounds like oil got cooked in the center section causing a clog.

 

[Defiant]

It's the way it was made. By dry cast I mean no water lines were cast into the center section of the turbo.

Hrmph, new term. Then apparently you aren't supplying enough oil to carry off the heat that the not-present-in-this-spool-water doesn't.

 

[Thomas91169]

was the oil supplied via the head or the oil sending unit?

and i would only run 10w30 synthetic.

 

[ddavisaf]

From the filter housing where the stock 2g feed line is from, except it's a stainless steel line.