View Full Version : Strange whine under boost

01-18-2013, 06:01 PM
Don't quite know how long it's been happening or if it's just my head messing with me. Under full boost (WOT, 9lbs) there is a distinct whine. Sometimes the turbo spool is louder than the whine, other times the whine is more than the spool.

It doesn't happen under light to moderate boost, only when I'm going WOT. I'm concerned it's the bearing going out. I'm changing the oil & gear oil this afternoon (it's time anyway).

I only have about 500-600 miles on this turbo. The other turbo I recall I did have some horizontal shaft play so I think that's what happened there. This one there was no shaftplay at all on it (vertical or horzontial) when I received it. I'll pull off intake and see if anything is out of place in there.

01-20-2013, 01:17 AM
Your already on a second st215 turbo?

01-20-2013, 02:29 AM
Yeah the one that came with the motor seized up on me. I was pissed at it so I just chucked it in the trash.

This one is starting to whine under heavy boost. Nothing in first gear (but of course I can't hear over the motor roaring). Second thru fifth gear I have a distinct whine over 5lbs boost.

Recent changes:
New oil pressure gauge installed. I don't recall if the whine was present before this or not.
Changed out gear oil for Redline MT90 with Ford XL3 modifier.

I'm concerned that it's the turbo bearing starting to go out. If it is, I have no clue how to address that. It's either lack of oil (or sub-par oil?) or lack of coolant. I'm not having any coolant temp problems (180* driving, 200 stuck in traffic idling). Oil pressure is great, 25psi when its hot at idle, around 50psi cruising in 4th gear at 45mph. Pressure goes up/down accordingly with RPM changes. I'm changing out my motor oil tomorrow for the Shell Rotella T6.

Right now I'm running Castrol GTX 10w30 in the motor for the second 'break in' flush (the first 4 quarts of oil I put in there were store brand CSK 10w30 stuff).

01-20-2013, 02:37 AM
You sure the 215 engine isn't designed for 5w30? Just something to think about. Any shaft play? Can you spin it by hand and listen or is it only is high rpm?

01-20-2013, 02:50 AM
I'll check all that tomorrow.

I know this turbo had none before, I'll see what it does now. I'm putting Shell Rotella T6 in it (5w40 I think?) tomorrow. I haven't been egging it since it started making the noise, I've kept it out of boost because of that reason. Just today though when we went to drive it I heard it loud & clear in 2nd gear and was like 'oh shit this ain't good' and decided to park it until I finish the fluid changes.

01-20-2013, 04:03 AM
Remove and blow through the oil feed and drain with compressed air.

If it IS the turbo making the noise, there is nothing you can do to save it now, but I suspect you're hearing something else.

It's got nothing to do with coolant flow, you could plug the center section coolant lines and it would be fine.

01-20-2013, 04:24 AM
Yeah it's just strange. If it was the turbo, I'd expect it to exhibit over a broader RPM range (and be louder frankly). I didn't think it was anything coolant related. Now that I think a bit more, it sounds kinda waxpaper between lips / kazoo-ish. I'll double check all the connections again. Seeing as how it's only under high(er) boost levels I'm wondering if I have a small leak somewhere and air is escaping and something is flapping in the wind.

01-20-2013, 07:46 PM
Sounds like a coupler to me?

01-20-2013, 09:52 PM
No excessive shaft play (in/out or vertical). There is a minute level of movement but not enough where it's contacting anything (which I think this is normal because of there's no oil pressure in the channels). I checked what I could see of the compressor housing and there is no scoring or damage to it. I just drained the oil through a magnet and filter to see if there's any particles in there. I'll slice through the oil filter as well to see what is in there (if anything).

I checked out the catch can and had maybe a drop or two of oil in there (after about 2k miles driving). Not bad at all. I did notice though that when I would blow on the catch can air would escape through the valve. I threw a new cap on it and no air escaping this time.

While I was there I decided to check out my line from the compressor to the wastegate actuator. it was starting to wear through again. I have this diesel high pressure rated fuel line with a kevlar exterior skin that I'm putting on. Should hold 1500+ PSI supposedly. I also noticed I have a part of the intercooler pipe with damage on it from coming in contact with the transmission mount bracket. It doesn't look like it went through, but I'll wrap it with electrical tape then slide a spare coupler I have over it to protect from any further damage.

More to follow after I button it back up...

01-20-2013, 11:13 PM
So indeed it was a kazoo effect from leaking air. I found 2 couplers that came loose (WTF is my problem!?) along with the oil catch can would seep air. I know the catch can isn't the problem because it's not holding the pressurized air but it was a possiblity. Threw on the new heavy duty kevlar covered line to the wastegate actuator and took it on a drive. No more whining over 5psi.

Just put in the 5w40 T6 as well. I can tell the idle is noticeably smoother. Pressures are about the same(ish). was holding 75 steady at cold idle, approaching 100 at 3k in 2nd gear.

01-21-2013, 06:05 AM
I was gonna say, sounds like an air leak