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-   -   Scary/Smokie oil leak at Boost! (https://www.miataturbo.net/prefabbed-turbo-kits-3/scary-smokie-oil-leak-boost-10044/)

mracer 05-22-2007 04:05 PM

Scary/Smokie oil leak at Boost!
 
Just limped here in to work. Was having some fun coming in to work, into boost hard, when I spotted a big "james Bond" type oil smoke behind me....:vash:
Pulled over, poped the hood, had some oil sprayed over the exhaust manifold, oil over the wastgate can, and some sprayed over the valve cover. Thank God the mobil 1 didn't catch fire? Anyways, looking around, and under the car, doesn't seem to be a big leak. Wiped it off with a cotton shop towel, started the car up, checked the guages, BTW, never lost oil pressure, looked for any oil coming out anywhere, didn't spot any more oil pouring out, no big puddle under the car.......?:confused: I'm thinking when I hit boost, was at maximum oil pressure, 60+ psi, that the line going to the turbo brg. has the leak? Can't look at it till I get home tonight. What do you think, the oil line feeding the turbo, the banjo, block feed, or worse, burn't it on the Turbo Tony DP?
Anyone "been there, done that"?
TIA
Mike

Braineack 05-22-2007 04:06 PM

check pcv valve.

Ben 05-22-2007 04:08 PM

is the dipstick seated?

MEatah15G 05-22-2007 04:30 PM

several things...for me when that happened i diagnosed everything and it ended up being a bad turbo seal...this can cause oil to be sucked out of the crankcase from the turbo and burnt up in the exhaust, causing dark smoke, especially at full boost. can also cause the crankcase to be pressurised... which would explain why oil was splooged all over your engine...

if it's leaking from what appears to be the turbo...the vaccumm line connected to in front of the turbo and head could have fed oil in there and it sometiems looks like it sprayed out of the oil feed inlet to the turbo if you get enough in there and slightly behind the compresser.

samnavy 05-22-2007 08:13 PM


Originally Posted by MEatah15G (Post 116050)
several things...for me when that happened i diagnosed everything and it ended up being a bad turbo seal...this can cause oil to be sucked out of the crankcase from the turbo and burnt up in the exhaust, causing dark smoke, especially at full boost. can also cause the crankcase to be pressurised... which would explain why oil was splooged all over your engine...

if it's leaking from what appears to be the turbo...the vaccumm line connected to in front of the turbo and head could have fed oil in there and it sometiems looks like it sprayed out of the oil feed inlet to the turbo if you get enough in there and slightly behind the compresser.

HUH?
The turbo doesn't suck up oil from anywhere. Oil is fed to the turbo via it's own feed line tapped off the block. Burning oil typically leaves a light-greyish/blue smoke, but not what I would call dark. A blown turbo seal would not cause a crankcase to be pressurized, although it may lead to burning oil if the oil made it into the compressor housing, through the intercooler, and into the combustion chamber. Basically your first paragraph is completely wrong.

Your second paragraph is mostly right, but needs to be explained better. The only vacuum line connected to the "front of the turbo" is the line for the wastegate actuator and does not carry oil. A large amount of oil may get into the intake from the "breather line" on the valve cover due to a pressurized crankcase (ask BRGRacer for clarification), and would make it's way to the exhaust through the compressor/IC piping/engine. Also, oil should never spray out of the oil inlet if you have the fitting tight enough, which there's no reason you wouldn't... and there is no access to the exhaust at that point... but it would make a mess.

Basically there are only 2 places for spraying oil to come from.
1. The valve cover breather line on the intake due to a pressurized crankcase. Fix: 323GTX PCV valve and catch can.
2. Dipstick popped up and sprayed oil everywhere due to pressurized crankcase. Fix: 323GTX PCV valve and piece of wire to hold the dipstick in tighter.

MRacer, are you running a restrictor on your oil inlet? When you pressurize the crankcase, it prevents oil from draining out of the CHRA, but since the oil is still being pressure-fed via the oil inlet, it blows oil past the wheels and into the compressor and turbine. Check your IC piping for oil. If there's no oil, then it definitely got into your turbine where it was burned. That's good, because it saves you from de-oiling your IC. Lowering the flow via a restrictor is usually a good idea even with no blowby problems.

MEatah15G 05-22-2007 08:54 PM


Originally Posted by samnavy (Post 116148)
MRacer, are you running a restrictor on your oil inlet? When you pressurize the crankcase, it prevents oil from draining out of the CHRA, but since the oil is still being pressure-fed via the oil inlet, it blows oil past the wheels and into the compressor and turbine. Check your IC piping for oil. If there's no oil, then it definitely got into your turbine where it was burned. That's good, because it saves you from de-oiling your IC. Lowering the flow via a restrictor is usually a good idea even with no blowby problems.

ohhhhhhhhh...it all makes sense nowwwwww.....when it was explained to me i was under a different impression...thank you for correcting me.

so a bad seal in the turbo could lead to oil getting past the seals from the oil inlet and actually making its way all the way to the compresser and get into your intercooler? or technically it could go the other way too correct? make it's way past the turbine in the rear and actually get sucked into your exhaust?

are you 100% sure that a bad/REALLY bad blown turbo seal coudln't lead to a pressurized crankcase....i've been trying to look it up...

Braineack 05-22-2007 09:01 PM

no. it couldn't.

the "seals" aren't even really seals. It's all dynamics.


the only way to pressurize the crankcase is from the charge pipes into the breather ports (specifically a bad pcv valve) or bad rings.

if the the turbo is spitting oil into the compressor, it'll get oil into the intercooler, but your crankcase isn't pressurized from it.

MEatah15G 05-22-2007 09:13 PM

well in that case...what is the easiest way to diagnose that you have a bad turbo seal? other then the infamous whine...

odviously they're not seals like a headgasket seal...but if something malfunctions in there... what is the most odvious symptom... don't worry i've read, i'm just curious as to what you guys have to say...

i guess what i was thinking was MAYBE maybe, if somehow the exhaust gas/pressure got past the turbine...could the it put pressure on the oil drain hose... or restrict oil feed? ...

i read that the mazda 323's turbo seals were prone to go out and that one of the signs was a pressurized crankcase....

mracer 05-22-2007 09:25 PM

I'm still here at work, so i really apreaciate all the idea's. But reading your reply's, and thinking back to where the oil was, it was directly under the little breather I have on the valve cover. When I go out to drive home, I'll place my hand under this filter, and see if it's weeping oil (soaked?)? Also check to see if the dip stick is seated? I'll get another GTX pvc too.

Samnavy: I'm not sure what you mean by a inlet oil restrictor? I'm using the stock Greedy oil supply line, with a direct drilled crankcase drain?
The ironic thing is that I had a split wastegate supply hose, and was hitting Big PSI #'s, get that fixed, back down to 8-10 and I spray all over...go figure LOL!
Mike

MEatah15G 05-22-2007 09:33 PM

yikes...man i was having this problem not to long ago and still is not fixed... is there a white gas coming from the head? what could taht be anyone?

samnavy 05-22-2007 09:50 PM


Originally Posted by MEatah15G (Post 116188)
... don't worry i've read...

Not enough.

Unless you've seen the inside of a turbo and know what all the parts look like, it's not gonna do much good to explain how the oil stays in the CHRA and doesn't leak out past the compressor/turbine wheel. Suffice to say, a good turbo shouldn't leak unless there is too much pressure inside the CHRA and oil is forced past the "seals", which aren't really seals. A turbo primarily goes bad over time as the bearings wear out and the shaft gets some play in it. Once the shaft has play, oil can start to squeeze past the sides of the shaft and into the exhaust/intake stream.

After several reads, I now understand what it is you're talking about regarding pressurizing the crankcase... AND NO. Exhaust gas coming out of the engine and through the turbine housing cannot get around the turbine wheel and enter the CHRA through the same hole the shaft goes through, and then proceed down the drain line and into the crankcase. If compressed air from the compressor wheel can't leak past it's seal, then non-pressurized exhaust gas has no chance.

A white gas coming directly from the head, ie between the head and the block is probably from the radiator. This would be indicitive of a blown head gasket and would be very obvious as you'd need to refill your radiator every other day.

MRACER,
Ah, sorry, forgot what forum I was in. The Greddy turbo is oil cooled and oil lubricated. You DO need a lot of oil flow. In a water cooled turbo, the oil only serves the function of lubing the shaft, and not very much oil is actually required... WELL, far less than an oil cooled turbo. So, forget about the inlet restrictor.

mracer 05-23-2007 03:06 PM

OK, stopped on the way into work and bought a 323 Turbo PVC valve, replaced it right there in the parking lot.
Earlier here's what I found:
Dip Stick was seated.
Found the air breather I have on the driver's side of the valve cover saturated in oil....this is what dripped onto the exhaust manifold causing all the smoke.
Drove gently into work (here now), didn't get into boost. When I opened the hood to put the new PVC in, didn't seem as if there was anything more than residual oil on the filter? HST, I have it wrapped in a shop towel to see if there's any significant oil still blowing through.
Anyway's on the way home tonight, I'm gonna boost and see what happen's?:crx: If it's gonna happen,...it's gonna' happen?! LOL!
Mike

Exhondaman 05-24-2007 12:40 AM


Originally Posted by samnavy (Post 116210)
MRACER,
Ah, sorry, forgot what forum I was in. The Greddy turbo is oil cooled and oil lubricated. You DO need a lot of oil flow. In a water cooled turbo, the oil only serves the function of lubing the shaft, and not very much oil is actually required... WELL, far less than an oil cooled turbo. So, forget about the inlet restrictor.

Wait,wait,wait...I've read elsewhere on here and even on my thread that some sort of inline pressure regulator should also be used with the Greddy kit because it could cause premature seal failure (like what happened to me), so which is it?

Braineack 05-24-2007 08:30 AM

No, the greddy kit uses a -3AN line as well as banjo bolts that reduce that size of the line. You do not need an oil inlet restrictor on a greddy turbo.

If other circumstances are causing oil past the seals of the turbo (or into the intake and one is assuming it's a bad turbo), doing a rebuild will not help. If you fix those circumstances, the turbo will not spit oil and will not need a rebuild.

MiazdaBLUE 05-24-2007 01:01 PM

so if the greddy kit has a restricter then the only way the oil is getting past is due to turbo seal problems?

how would not rebuilding the turbo help?

Braineack 05-24-2007 01:36 PM

the greddy doesnt need a restrictor, it's never had a problem with too much oil pressure like most Garretts do with -4AN lines.

----

now say for example your oil return line was the stock Greddy 5' hose. And lets say you didn't do a great job of maintaining downward travel and there are a few uphill slopes. Well that oil is not pressurized, so it's not going back into the pan, so the oil will start to build up in the line untill it get filled up and backs up into the turbo. at this point since there is oil pressure inside the turbo, the next best place for oil to exit is the compressor and turbine seals on the shaft.

or, your pcv has a small leak and lets boost pressure into the crankcase. Since the oilpan is within the area, so is the oil return line. since there is no pressure inside the oil return line, oil slowly drips back into the pan. if you apply positive pressure inside crankcase it will make it's way up into the oil return line, forcing the oil to backup into the housing...and you know the rest.

or, not typically greddy related. you have too much oil pressure in boost. it cannot drain fast enough. so it exits out of the seals as well as the return line. most likely it will smoke in/out of boost and at idle.

you fix all of these and the turbo shouldn't need a rebuild, if that's the reason it's happening.

Exhondaman 05-24-2007 05:43 PM

^Thanks brian, I just took my turbo off to rebuild it and I'm gonna re-think my oil feed and return line situation when I put it back in. BTW, the blades looks brand new, thats good a thing at least!

bripab007 05-25-2007 08:27 AM

What? Did someone say my name?

mracer 05-25-2007 03:32 PM

Ahhh Sh*t!
Just came into work , did the Smoke screen again, poped the hood, oil sprayed all over the engine coming from the breather!:vash: I think I must have hurt the engine on some previous (unintentional) high boost.:eek:
As mentioned here earlier, did I pooche the rings?...or what? Head gasket/valve seals? Surprisingly, the engine still runs strong? Could I buy some time with a Greddy type oil catch can, or do the dirty and just run a hose to the ground? Or am I on borrowed time? Start looking for a new engine....:cry:
TIA
Mike:sadwavey:

MiazdaBLUE 05-25-2007 03:44 PM

honestly, you are probably still making good compression.

I'll bet that it is the valve seals, probably not the headgasket unless there is oil coming out from your where your head and bottom end meet.

TRY NOT RUNNING THAT DAMN FILTER, run it to a line right before the turbo. This better helps the seals seal.

I had this same problem and it ended up not being the rings.
although i am still not sure of if it is my valves or not. I'm in the middle of rebuilding my turbo...peace.


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