where'd my boost go?
#21
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A ingested a screw; it got lodged in the turbine blades which ultimately bent the shaft slightly. This caused the bottom edge of the turbine to make contact with the heat/oil shield thing and slow the wheel. You can see from the dyno my spool speed slowed significantly and I couldn't raise my peak boost. Otherwise it ran normally and didn't make any noises.
#22
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don't run a restrictor , talked to a professional at turbo exchange in charlotte nc and he told me i would make a mistake running a restrictor. i don't have one and had the turbo on for 15 month now no problems. restrictor= ball bearing. not enough oil can damage the bearings and lead to shaft play and than oil burning. i trust this guy since he rebuilt my turbo and guaranteed 1 year for the work. i'd check wastegate or leaks.
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I absolutely have to run a restrictor. With my -4an feed line, I pass WAY too much oil. A turbo shouldn't see more than 30psi of oil pressure and we see upwards of 90psi towards redline. Those with a -3AN line can get away without one, as the flow volume is that much less, but my turbo will smoke at idle without a restirctor and I had to even go down from a .060" restrictor to .040" orifice. It's common to see a journal bearing turbo need one, not so much with ball bearing turbos as they are integrated...Do a quick search on any boosted honda forum and you'll see the majority of users will have one.
If you can get away without one, more power to you, but there's no yes no answer. I'd rather run my .040" and have no issues or failures than to run without one and die suddenly on the road due to either fumes or the smoke screen left behind me preventing a semi form seeing my brake lights...
If you can get away without one, more power to you, but there's no yes no answer. I'd rather run my .040" and have no issues or failures than to run without one and die suddenly on the road due to either fumes or the smoke screen left behind me preventing a semi form seeing my brake lights...
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i called the guy up at turbo exchange. he's got 30 yrs of turbo experience. asked him if i should run a restrictor with the 4an line. answer was absolutely NO. even at 90 psi he said with a good drain you don't need a restrictor. he said you need volume in a journal bearing turbo and with a restrictor you reduce the volume causing bearings to run dry. His answer for a journal is that you never should run a restrictor with a good drain setup. a drain he said has to be angled a bit when it comes out of the turbo and can not go straight down and into the oil pan. it will reduce the flow of the drain if it is not angled he compared poring a beer if you slant it it flows better than if you just turn it upside down. i mean this guy can school all of us on turbos all day long. great guy to talk to if you need a rebuild. no BS here.
by the way check this out
http://www.tepturbos.com/troubleshooting2.htm
by the way check this out
http://www.tepturbos.com/troubleshooting2.htm
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Before I made the decision to drop the restrictor, I went through garrett's site and there are no recommendations for journal bearing turbos, only bb. But in Scott's case it's working for him and I'd do the same. OTOH If the guy who is putting a warranty on the turbo tells me not to, then I won't. Mine came from TunerToys and they said it was not needed.
That's a nice chart, but I think I'm beyond that. I just went out and looked closely at the compressor inlet. What I thought were scrapes were actually incoming air swirl marks in the light oil film (from the air filter). They're now gone and my finger tip is dirty.
The wastegate is fully closed at rest too. So I'm going to build one of those inlet pressurizer leak tester things since I found all the junk needed and I've got a secondary regulator on the compressor. I hope it's a leak in the IC piping... then again the actuator could have unstuck as I rolled in the driveway.
That's a nice chart, but I think I'm beyond that. I just went out and looked closely at the compressor inlet. What I thought were scrapes were actually incoming air swirl marks in the light oil film (from the air filter). They're now gone and my finger tip is dirty.
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![Doh](https://www.miataturbo.net/images/smilies/doh.gif)
#26
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there are more cases than just me were people absolutely need them with high oil pressure motors, such as the honda crew.
it's also possible the seal to your compressor housing is leaking...i believe that happened to magna-mx5.
it's also possible the seal to your compressor housing is leaking...i believe that happened to magna-mx5.
#28
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if the shaft play is tolerable than there should not be any leaks. i took my turbo off the other week and thought the seals are done just to find that my drain sucked. took the turbo down to turbo exchange and the guy told me to recheck my drain since the turbo had normal shaft play. now i redid the return with a copper pipe and some bends, no more smoke and still no restrictor. but in some cases it may need it if seals are not in the best shape. went with the 3/4 inch pipe and don't think there should be any problems. good luck and keep us updated.
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I went ahead an pressurized my IC piping and had a nice leak... in my WG actuator hose. Check out the "fingers" on the oe vacuum hose clamp at the compressor bung- it made cut about 1/3 of the way through the other hose. Apparently it rotated on the trip.
I don't know if that's enough or not, I'll test it out this weekend. As a bonus, I found out my throttle body is leaking a bunch of air into the manifold, which IMO explains my 1200 rpm idle with the idle screw totally shut.
![Doh](https://www.miataturbo.net/images/smilies/doh.gif)
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#31
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Me neither. And a drive showed it was only leaking 4psi of boost (actually more than I thought it would show). Now I'm peaking at 9 around 6k. Unfortunately I found out a new noise is not what I thought was a heat shield rattle. It was still there once I removed the big shield and stabilized the dp shield with a screw drive. It's either a rattle, scrape or a leak. I hesitate to guess, but my experience has showed that turbine scraping usually shows on the other side as compressor scraping- of which there is none. I'd think the likelihood of a failed SS Autochrome manifold is greater, given the sustained temps of the last road trip. It hasn't seen anything near that- just a <2 hour road trip prior, and the usual tuning runs. Well, enough speculating - a tear down will tell. The wastegate housing comes off in minutes and that'll let me take a peak at the turbine. ![eek5](https://www.miataturbo.net/images/smilies/eek5.gif)
Here's the vid:
![eek5](https://www.miataturbo.net/images/smilies/eek5.gif)
Here's the vid:
#32
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- Gate seal
- Gate actuator bent/loose
- Gate actuator spring broken/weak
- Plumbing leaking
- Ex mani leaking around gasket
- Compressor housing seal etc etc.
You have a three possibilities disregarding damage :
- Boost leaking out between compressor and valves
- Exhaust leaking out between valves and turbine
- Exhaust leaking past turbine
On to the side topic :
Hmmmmm
I was going to add the restricter back in IF I saw smoke- but it's yet to happen. So the housing is either sufficiently restricted as-is or it doesn't need one regardless. I was running one before on the previous turbo before something chewed up my turbine blades. But I can't find an argument against more oil flow if it's not causing problems.
don't run a restrictor , talked to a professional at turbo exchange in charlotte nc and he told me i would make a mistake running a restrictor. i don't have one and had the turbo on for 15 month now no problems. restrictor= ball bearing. not enough oil can damage the bearings and lead to shaft play and than oil burning. i trust this guy since he rebuilt my turbo and guaranteed 1 year for the work. i'd check wastegate or leaks.
but my turbo will smoke at idle without a restirctor and I had to even go down from a .060" restrictor to .040" orifice.
It's common to see a journal bearing turbo need one, not so much with ball bearing turbos as they are integrated...Do a quick search on any boosted honda forum and you'll see the majority of users will have one.
Why be a sheep?? Even if 1000 15 year old prepubescent honda owners ran a restrictor without issue I would not.
there are more cases than just me were people absolutely need them with high oil pressure motors, such as the honda crew.
Seriously though :
Excess oil pressure and volume PAST the bearing WILL kill the seals.
This is true but = bad drain or cheap/nasty/damage/worn out turbo.
Not a reason to starve the turbo... Saying you are giving the turbo too much pressure or flow is like saying you are giving your mains or big ends too much pressure or flow, ie, just silly.
I put way too much time into convincing Rob to ditch the restrictor to allow you buggers to even think about swaying him the other way.
10/10 for musanovic
Fred.
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I've had my own personal and friends setups that ran journal bearing turbos.
Unrestricted they'd blow oil past the seals. Restricted with a simple .060 fitting and they were fine again. These are with -10AN drains, no kinks and smooth flow.
I will always run a restrictor on my journal bearing turbos.
I only speak from my own and my friends experiences.
Unrestricted they'd blow oil past the seals. Restricted with a simple .060 fitting and they were fine again. These are with -10AN drains, no kinks and smooth flow.
I will always run a restrictor on my journal bearing turbos.
I only speak from my own and my friends experiences.
#34
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rb26dett, next time you're in DC I beg you to come over to inspect my drain line. Then we'll hold hands after we remove my restrictor and watch the pretty blue smoke at idle as my turbo dumps oil past the rear seal into the exhaust...
Rob and I have already had this discussion, and I never tried to convince him to use one, only that I needed one. I would never had talked about a restrictor in this thread if patmx5 didn't start talking about one.
I would also like to correct myself where I said 30psi of oil pressure, I did mistype. I meant to say 60psi (you can go back to my thread history and see where I've used this number a few times on topic). The number was from two good sources:
also, let me know what size I should upgrade my vertical -10AN (5/8") line to please.
I shouldn't even had repsonded to your post; I have boost, it's worked for years, so **** you :P
Rob and I have already had this discussion, and I never tried to convince him to use one, only that I needed one. I would never had talked about a restrictor in this thread if patmx5 didn't start talking about one.
I would also like to correct myself where I said 30psi of oil pressure, I did mistype. I meant to say 60psi (you can go back to my thread history and see where I've used this number a few times on topic). The number was from two good sources:
Originally Posted by Maximum Boost
Too much oil pressure can create problems with turbos. It is possible to force oil past oil seals that are in perfect condition if oil pressure exceeds 65 to 70 psi at the turbo. If a particular engine creates more oil pressure than the seals can handle, it may be necessary to install a restrictor or bypass system to reduce pressure at the turbo.
Problems of oil pressure overpowering the seal are evident in a frequent if not quite constant smoking problem. Anytime oil pressure exceeds the 65-70 psi range and smoking persists, a restrictor or bypass should be installed prior to any other changes.
Problems of oil pressure overpowering the seal are evident in a frequent if not quite constant smoking problem. Anytime oil pressure exceeds the 65-70 psi range and smoking persists, a restrictor or bypass should be installed prior to any other changes.
Originally Posted by Garrett Turbo
Garrett ball bearing turbochargers require less oil than journal bearing turbos. Therefore an oil inlet restrictor is recommended if you have oil pressure over about 60 psig. The oil outlet should be plumbed to the oil pan above the oil level (for wet sump systems). Since the oil drain is gravity fed, it is important that the oil outlet points downward, and that the drain tube does not become horizontal or go “uphill” at any point.
I shouldn't even had repsonded to your post; I have boost, it's worked for years, so **** you :P
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But don't you guys (outside of fred) agree that if the oil pressure isn't blowing out the seals, then the bearing should be fine? I don't see how high oil pressure can harm a bearing. I'm still waiting for Pat to explain "wash out".
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#38
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Then we'll hold hands
after we remove my restrictor and watch the pretty blue smoke at idle as my inadequately drained, chinese, improperly rebuilt or poorly designed turbo dumps oil past the rear seal into the exhaust...
I would also like to correct myself where I said 30psi of oil pressure, I did mistype. I meant to say 60psi (you can go back to my thread history and see where I've used this number a few times on topic).
The number was from two good sources:
Reference two has no link or context. When and where did which Garrett employee say this? Link please??
also, let me know what size I should upgrade my vertical -10AN (5/8") line to please.
I shouldn't even had repsonded to your post; I have boost, it's worked for years, so **** you :P
And tell us about the origin of your turbocharger.
Was it brand new? If so, which reputable manufacturer produced it? (I'll accept borg warner and holset as valid answers, garrett, maybe...)
Was it rebuilt? By who? Are they any good? How do you know?
Was the answer to question A this :
![](https://upload.wikimedia.org/wikipedia/commons/thumb/9/92/Flag_of_the_People%27s_Republic_of_China2.svg/800px-Flag_of_the_People%27s_Republic_of_China2.svg.png)
Basically for your turbo to gush oil through a seal like that at idle means your seal is already history or you have some blockage below it.
http://www.teamlorenz.com/images/insidelg.jpeg
http://www.jhdiesel.com/Turbo_Cross-Section.gif
http://www.cad.pl/rys/Turbo-Sprezarka.JPG
Note the size of the orifices leading to bearings and other regions. Something is not right with your turbo or setup. That something could just be that it's an OLD garrett design = a poor design. Is there a thread with your setup in it already so we can diagnose your issue out of Rob's way?
Fred.