I have a TO4B v-trim hybrid turbo on my FC, with an S5 hot side. I rebuilt the turbo with a kit from G-Pop shop, but didn't balance it. Now, I don't think that was the issue, and I'll get to that later. So after I assembled it and installed it, it didn't leak, spooled up fine, great. Tried getting a tune on the car, started hearing noises from the turbo area, exhaust started smoking blue. Took the turbo apart, found out that the nut that holds the compressor wheel was gone. Later found it in the intake. So, that destroyed my compressor wheel. I bought a new wheel, started re-assembling and damaged the turbine piston ring seal. I got a brand new T3 piston ring seal and carefully reassembled it. That's when I realized that the last one didn't get balanced, and I should probably do it before I blow this one up too. So, I get it balanced, and the guy said it probably didn't really need it, they balanced out fine (he does them individually). So I figured that couldn't be the reason why the nut came loose. So, carefully re-assembled again, great. Started the car up, no issue for a few minutes, rev a few times, start hearing noise, start seeing smoke. Shut car off, took off intake found nut BARELY holding on to the turbine shaft.

WTF??? It did it again? How is that nut backing off!??

 

maybe stalling the compressor against the cover and the shaft is still trying to turn,, undoes the nut
it may be because the shaft has been bent when you disassembled it first time

however excessive axial movement will do same
check your 270 bearing has wiping area left on both sides of the bearing
( the raised area that rubs away as it wears )
and check you have the bearing collar installed with its flat side towards the front seal

,, importantly,, double up the spider washer in the front cover backing plate to combat the axial loading
and use locktight compound on the nut !

 

It's got a 360 bearing, and the collar will only assemble one way (this I know )

The bearing has some slight wear on it. You think that could be the issue?

And what color lock-tite should I use?

 

red locktite 271 is what i use

check the shaft against a straight edge , check the backing plate and cover for signs the compressor has touched them , replace the worn bearing
use carb cleaner to purge through all the oil galleries in the CHRA

 

Shaft is definitely straight, it'd have red-flagged the guy who balanced it, and I spun it a few times upon completing the rebuild to see if it had any wobbles. I'll straight edge it just to make sure, but there was absolutely no wobbling. The compressor housing got a little scratched from the original wheel chewing it up, but I don't think it's touching anywhere now.

I think I'll have to get a new rebuild kit with all the goods and see where that gets me. I hate throwing all this time and money at it though. I keep thinking that I'm doing it right, and it still takes itself apart each time.

 

red locktight is your friend

 

http://www.rotomaster.us/index.php?p=section&sid=29

 

Very, very good information. I think I need to figure out how to install a PCV system now (might explain the smoking), and I probably need some red loctite. Thank you!

 

Really hope u get this fixed asap!

 

since the nut came off, check the inducer fins on your turbine wheel. i would bet they are all worn down from rubbing on the housing, which can cause slow spool up. its nothing too serious, just a heads up if you happen to have an other you can replace it with laying around

 

I *JUST* replaced it. Literally, I just had this issue and bought a new wheel, then this started happening again. Didn't even drive the car more than 10 feet (pulled it out of the garage) and sat it in the driveway when I started hearing the clinking noise. So no damage done to the wheel yet. I'm going to try fixing it one more time, then I have a backup plan if all else fails.

I bought some supplies to make a catch can to hopefully fix the smoking issue. It's makeshift, so don't mock me, but I need something quick so I can get the car running for an event this Saturday. So I take a trip to Lowe's to find an air compressor moisture trap, but they were out for some reason. Next best thing was to make something quick, so I took a trip to the plumbing section and got some 2" PVC pipe and a couple end caps, then drilled 2 holes and installed 2 5/16" barb fittings. Ghetto, but it'll work.

Anyways, I searched around and got some different information on routing this thing. I figure that it needs a vacuum to keep the blowby gasses out, so one side needs to go to manifold vacuum, and the other goes to the center iron nipple with a check valve to prevent boost pressure from pressurizing the oil pan. But here's the catch- under boost there will be no vacuum sucking gasses out of the oil pan (or, the "crank case"). But that's when I need the gasses gone the MOST. So someone recommended putting a breather filter on the oil fill tube. But that's connected to the center iron, so that'd be like having the manifold vacuum sucking in air through the breather filter.... i.e. a vacuum leak. So now what?

I got some loctite, so tonight I'll pull the turbo...... again....... and re-try.

 

A catch can doesn't need vacuum.

thewird

 

Explanation?

 

Shaft is straight, I just checked it. Took about 15 minutes to remove the turbo this time, and that includes gathering tools and jacking up the car to drain the coolant. I'm pretty efficient at this now. Shaft looked good, bearings still look good, got a little wear on the thrust bearing, but there's no play so I'm not too worried. You were right about the turbine wheel this time. I misread your post and thought you meant the compressor wheel. The compressor's still ok, it's the brand new one. Of the 3 times it's taken itself apart on me, the last time was the weirdest. The turbine wheel did get a little worn on the edges, but just minimally. I measured it against another turbine (I have a few hanging around) and it's only worn down just a little. No rubbing once I got it back together, and things are spinning freely again. We'll see this time if it comes apart after the red thread locker. I'll be surprised for sure if it does.

I'll throw it back on tomorrow and see how things work out for me.

On a much lighter note, a friend of mine jokingly said I should use JB weld instead of that ***** red threadlocker. Well, I think he was joking...

 

connect the vacuum nipple to the aircleaner ,, this is the direction the stock system will take when boost pressure is in the inlet manifolds,, defeating the low speed purge path directly to the TB

there is many schematics showing you the fundamentals of the basic setup,, and you should try and emulate that high speed circuit
( building back that low speed part of the purge circuit is going to require a purge CV -or purge solenoid and some switching and is often avoided in cars with the nest delete )


and yes,, in my experience,, you need a vacuum to get it to work well without turbo smoking
( AS THE LINK CLEARLY DEMONSTRATES )
,, and not just fill up as an extra sump space

variations would be no can,,, and the top middle plate filler nipple towards the air cleaner ,, and the lower one to a breather
( with an inline one way valve arranged to only draw fresh filtered air towards the sump space,, never out )
this system will draw fresh filtered air across the sump space and provide a permanent mild vacuum
( it is feasible a can could go into this system,,but will have no direct direct drain back to the sump )

variations with can ( and no filter ) would have the upper nipple on the middle plate filler to the can middle nipple
can upper nipple to the aircleaner,, can lowest nipple to the lowest nipple on the centre plate
( and can mounted higher than the nipples )
would amount to a permanent scavenge ( which the turbo requires )
but the can works as a knock out pot / demister pot and will always drain when the car returns to idle


IMO if you dont grasp these basic concepts,, and think catch cans are merely extra sump space,, you missed the boat badly

 

Aren't the middle iron nipple and filler neck nipples open to the same space inside the engine?


BTW, what link clearly demonstrates it??

 

yes,, both nipples go to same space,, they are there for IN and OUT
ie- the stock intention,, a flow across the sump space of filtered purge air towards the engine

if you are wondering-
the drain will return to the sump when not under boost because it always has a gravity head pressure above the vacuum seen in both the sump space and in the can

http://www.rotomaster.us/index.php?p=section&sid=29

this link,,

 

So it's not a direct shot from (lol) nipple to nipple? Is there a baffle of some sort in there to allow air to flow across the sump space instead of being sucked from breather to intake?

 

there is no baffle, i suspect by intention

in the stock setup it will still provide a mild vacuum on the space,,
( good,,as a strong direct vacuum may also have its own issues )
amounts to cutting the fume content with the purge air and not taking it totally
so some control is there on the immediate hydrocarbon content and there is less chance the fumes will carry liquid over

they also only intended to take the volatile fume fractions
( whilst providing the vacuums necessary to make the turbo and rotor oil gravity returns work properly )
and these volatiles would collect naturally at the highest parts in the sump spaces

 

oh,, and if i neglected to mention it
put the red stuff on the threads , TQ the front nut to 12 ftlb and THEN make an angle based movement of 30- 45 degrees
( don't make me post why )

 

Looking forward to seeing this self-loathing turbo on Saturday!

 

I think I get it now. It seems like there's 2 modes of operation here.

At idle or high manifold vacuum, the air will go in from the filter, to the catch can, through the bottom nipple, through the engine, through the check valve, to the intake manifold. This removes what little blowby gasses accumulate in the crankcase. Once under boost, the check valve will shut, and the blowby gasses will pass through the lower nipple and go out the filter via the can.

(found the drawing here: https://www.rx7club.com/showthread.p...l+catch+%25can )


Wouldn't it make more sense to have the can between the upper nipple and pcv valve though? Maybe not, I'll probably just push my "I believe" button and go with it.

 

dont use that diagram, that is also far short of the mark, another case of NFI


yes the STOCK system has two paths, one towards the TB at low load,, other towards the aircleaner at higher load and boost

with a catch can and without complicated switching or one way valves you emulate the high speed circuit full time and ignore the complication of purge valves

it is impossible for me to describe a system for you if you have an unknown catch can with unknown number of nipples, unknown if it has a drain, unknown if it is a type with a breather on top

ALL of these make for a different scenario and different approach

catch cans SHOULD be by intention a knock out demister pot ,, there to condense and trap the heavier fractions in the fumes and return them to the sump
whilst providing that vacuum necessary to prevent the sump space from building pressure

as such,, in a turbo application,, it should have no vent filter on top
it should have a drain nipple at bottom,, a middle inlet nipple,, and a higher "to vacuum" upper nipple

if your can is not arranged so,, it is a poor joke intended just to look good,, or for an NA oldschool application

i am not in control of the idiots that churn these out with no thought for their application on a turbo car
all i can do is point out that many catch cans on the market will never be functional in this application due to simply being and incorrect or not thought out design

if you retain the standard charcoal trap in your bay,, and just want to delete the nest and low speed purge stuff ( without a can )
then your system will look a little like this -




IF you wish to use a catch can ( without a vent on top ) it will look like this
if you have the charcoal can and fuel tank vent it can be teed into the vacuum line
[ use an NRV on the charcoal trap line ]




----------------------
OT

these are VERY basic concepts that it seems no-one wishes to use thought and apply to their specific catch can and engine

to other readers
- dont send me a PM asking me how this works for you
i seem to type it endlessly for morons
\and if you dont want to use search,, or apply your own brain,, so be that your problem

as you can see i find it frustrating to deal with people who cannot 1st adequately describe their system or apply thought
and expect me to cover all bases with 10 000 words , OVER and OVER for the same concepts

this will have been the third time this week i have had to spell it out over several forums
,, exactly the same questions,,the same " why does my turbo smoke "
and it seems-
"yet i want to keep shiny metal can in my bay that does nothing but look good and i dont want to change anything"

 

Haha, my can... not shiny or pretty. I actually don't want it for how ugly and how much space it takes up. Turns out, BECAUSE of searching I figured I needed one, and confused the **** out of myself in the process.


Exactly. That's all I want it for. I need it to remove the vapors, hopefully prevent smoking, and separate the oil mist from the vapors. Returning the condensate back to the oil pan is really tertiary to my necessities. I'll just drain it once an oil change.

Like I said, my "catch can" is just a short sealed off section of pipe with 2 nipples and a drain plug on the bottom. A basic moisture separator. Nothing more, and no vent filter horse **** on top.

Sorry if it seems like I'm not grasping the concept... I really do get the concept, it's the terminology that I've never heard before that boggles me. When I say vacuum, I think manifold vacuum. I didn't think that you meant pre-turbo "vacuum". Sure, it's a vacuum, but not what I thought you meant.

Thanks for the drawing. Makes much more sense than the other bullshit I found by searching.

 

Turbo re-assembled with red loctite this time. It's staying together, and I drove it down the interstate to a weekend rotary meet. Thanks for all the help! My makeshift pcv system works well too. No smoke either (save for the black smoke due to the very shitty tune).



Red loctite is some very serious stuff though. I assembled a 13b eccentric hub with red loctite, and absolutely destroyed a Snap-on 19mm impact socket trying to remove the hub bolt. I can only imagine what it'll do to a .25" turbine shaft if I ever have to disassemble it