helihansen

After boosting my car lays out a huge cloud of smoke. But it only does it on decceleration. Car runs fine and doesnt smoke any other time. From what I am researching I believe it to be my secondary turbo. Can I just rebuild that one turbo for now until I go single? Thanks

Scrub

iTrader: (25)

what color is the smoke? It could be a few things.

93BlackFD

what's your PCV valve/crankcase ventilation setup?

helihansen

Smoke is blue. I am running the stock pcv system. If it were my secondary wouldn't I notice there being oil in the I/C pipes? I havent noticed any of the pipes being oily and also have no other leaks or problems. The car is set up for N/S if that helps. Thanks

93BlackFD

check the PCV valve, make sure it's one way

mad_7tist

sometimes the trubos will leak oil on decel worse than on accel so that is when you notice the smoke

helihansen

Do you guys think its feasable to just rebuild the secondary while I have it all apart anyway? Can the Pcv system cause that much smoke? Im talking like it looks like when a car blows their head gasket I cant see behind me.

spoolage

iTrader: (2)

Do this.

There is a one way valve, i think the PCV valve connected to the Oil Filler neck. Uhook the hose connecting to the neck, just pull it off. See what happens. I had a similar problem and thought it was the turbos only to realize that when I had been a dumbass and decided to cap the nipple off, I was actually causing the oil chamber to pressurize and since the air couldnt go anywhere, it forced extra oil into the turbos causing them to burn off.

helihansen

I will check the pcv system. How much shaft play is neccessary for there to be oil leaking by? I have my turbo's out anyway because I did the full N/S so I will have to wait until its back together to really know. I just dont want to put it all back together and find out I have the same problems. I am goin to search but can I make a fool proof PCV system or make some kind of an upgrade so I dont have to worry about this? Thanks

RotorMotor

iTrader: (5)

you know i have been getting the same thing the last few days (and the secondary doesnt seem to work sometimes as well).... anything above 4.5K rpm blows a huge cloud of smoke (accell & decell). smoke is blue so its oil....

spoolage

iTrader: (2)

none. I had a bran new set of rebuilds and it did it, took the cap off and wala!

spoolage

iTrader: (2)

well, my fool proof pcv is, no hose.. heh, its supposed to circulate air back into your UIM, the reason its a one way valve is to keep pressure OUT of the oil chamber.

so i guess a fool proof method could just be removing the thing entirley, I've noticed since I did this I get no oil residue in the UIM at all.

helihansen

Ive been reading here and my senses tell me to put the turbo's back together and work on the pcv system. I dont want to spend money on a rebuild if I dont need one. Ive read about some other people's solutions involving catch cans. Spoolage dont you need some kind of ventilation rather than just capping it off? From my understandings the people who had the most problems after installing catch cans were the people who autocrossed and constantly had their car pulling g's which would ultimately slosh oil back up into the filler neck.

93BlackFD

that's not true, it causes your "crankcase" to presurize (i.e, oil passage all through eccentric shaft, jets, bearings) which causes your oil control rings to float, and you get blow by

not the turbos....

rdavidsrx7

Yours sounds almost exactly the same as what mione was doin, see the bottom of my thread for what I found.
thanks again to all the people that led me in the right direction!
https://www.rx7club.com/showthread.p...hreadid=290697

BoOsTin FD

What I want to know about this PCV valve thing is, 95's dont' have pcv valve. Can't we just plug this up too and have only the other passage that goes from primary turbo inlet hose to the oil filler neck?

I saw this on Rob Robinette's web site about taking out the PCV valve. But some of you have said that if you plug it up, you might get that smoke. I get that smoke too on deaccelleration, and my turbos are rebuilded.

Amel

93BlackFD

that would work

clayne

PCV or not, you still need a place to vent crankcase pressure. Catch can is typically what people use.

93BlackFD

and running a line from the primary turbo inlet elbow to the filler neck accomplishes that....as i stated above

helihansen

93 black fd but what about if you are corenering hard? Wont oil creep back up into the oil fill neck and therefore be fed into the primary tube?

helihansen

?

helihansen

?

helihansen

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