johnrx2

I just bought this fc from florida very clean car. One of the nicest fcs ive seen. Car specs
93 rew motor
Gt 40 turbo
Microtech
S5 front cover and cas
93 intakes
503whp on e85
Compression. 92 front 90. Rear piston tester 5000 on build large street port
Car starts hot perfect coolant temps perfect
I test drove the car in florida it smoked a little but did not seem as bad as it has been latley.
My old car did this a little so figured just a premix thing
This car had omp w rod connected. And premix 1oz per gallon
I removed the rod and i could still see oil in the metering lines .so i put reg bolt in place of banjo style tonight.
The car will smoke whitish w blue haze(oil) until it is driven afew miles. If it just sits and idles even up to operating temps
Still smokes. If you drive and abuse a little it will b perfect for the rest of the day.
I changed oil today to thicker oil w some smoke fix thick **** in there as well since i now deleted omp lines should b ok
-things i found. Catch can more than half full i drained mostly fuel ,moisture and light oil mixture.
-Oil had e85 fuel odor to it
-rear lower spark plug hole had oil around it but not on the face or part that would b in the engine. Maybe something. Leaking in motor right there
I have video of smokeon my phone but cant upload
Would love to here some feedback from builders and rotary vets
Thank you
John

johnrx2

Also ive searched this website and internet for the prob and found many things causing smoke
Oil seals in engine
Turbo seals
Crankcase ventilation
This one has catch can w breather hooked up at nipple on oil filler neck 93 motor
Appears to b hooked up correctly
Did notice some condensation on inside of oil cap when i took it off today

johnrx2

Anyone have any thoughts or have similar experience . really want to figure this one out .

johnrx2

Bump

johnrx2

Am i posting in the wrong section

HKSpoweredFC3S

Have you checked the compression sense this started to happen?

johnrx2

When i went to florida to drive it was smoking a little but we got in from cold start and started driving . did not seem to bad then. We did compression. Test while i was there 92 and 90. The old owner took car back to dyno before i bought it. And sent video with paper of date compression test again after dyno the same. Car starts hot or cold everytime.
I did pull the hot pipe off turbo and found some oil ill post a pic i also posted in single turbo section when i found the oil in charge pipe
I hoping its a turbo issue rather than engine. Maybe the turbo seals got worse after the dyno day

HKSpoweredFC3S

definitely turbo related weather it be seals, restrictor, feed lines, catch can, what have you, also you mentioned how there was oil seeping from one of your spark plug holes, could be something as simple as tightening it down to make a good seal.

johnrx2

Yes when i pulled the spark plug out it did not seem tight and the little oil was not on the tip.but on the outer threads. Spoke to a guy from atp turbo about a restrictor and he said to add a second breathrr for the crankcase 1st then if there is still a problem then a restrictor will b needed. I ordered all the an fittings and hose hoping it will be in by yhe weekend so i can add the other crankcase vent.
Thanks for the replies .i will post backonce i have that part done

HKSpoweredFC3S

good deal

BezRx7

I have this exact issue!!

Jdm s5 streetport, borgwarner s300 .88, fresh build with RA SuperSeals, all new mazda seals/springs etc.. 94/92 compression etc

I have omp disconnected and also see oil in the lines etc was using idimitsu racing premix so thought it was the omp and premix causing excessive oil/smoke

I am also running a crushed s5 oil pressure regulator so oil pressure is up! so I think my -4AN oil feed line and supplied oil restrictor are still not dropping the pressure enough! I want to switch to a -3 oil line before scrapping the turbo... Have had this happen with a nissan ca18 motor and simply switching the restrictor and line sorted it out (also a fresh build) and the turbo lived for a few years on stupid abuse.

The rx7 would start up and smoke and smoke and then after a 30 mins if light break in driving it was idling clean as a whistle, so smoke to speak of, but after parked up idling it would slowly start back

I had no catch can or breather hooked up, (fresh build) from reading online I saw suggested that the nipple on the oil filler neck should see vacuum (not boost obviously) so quickly ran a line to the manifold and on start up smoke went down dramatically. Added a one way valve and took it for a drive and vacuum was up (~17-18hg) and strangely my AF settled at ~13, came back and no smoke to speak of until it idles for about 5-10 mins.

I have not really went into boost as I am breaking in, but want to get it as clean as during break in as a sloppy break in with excessive oil or fuel can lead to issues when you start to boost and clean up the mixture if you have not ruined your turbo with too much oil pressure.

So I'm gonna run a proper catch can with vacuum supply and a new oil line and restrictor and see if that helps.

BLUE TII

iTrader: (9)

Make sure the "vacuum" lines from the oil injector tops/fuel injector air bleeds goes to a NON vacuum source (one that sees boost, but not vacuum).

I see this hooked up wrong all the time on builds and then the engine sucks oil in through the tops of leaking oil injector checkvalves on start up.

johnrx2

S300 i had same setup on my last car with s5 motor i think i just left it vented open by oil filler neck and did not have smoke problem. I liked that turbo 418whp at 15 psi pump gas and it would whistle a little when coming out of vacuum. This car is a turbo2 but has rew 93 motor somay b diff.if you figure out anything w your smoke let me know.

Also blue tii. I put non banjo bolts through the omp lines so eventually there should not be any more oil in those lines . im premixing anyway. My last car i had no omp and premix on ly no prob.

johnrx2

Installed the second breather line. It smoked still but it took longer to start. Today im driving it a little then will let it sit for awile 5hrs or more and see what it does. If not fixed restrictor will b next step

johnrx2

Udate ordered a vibrant oil restrictor from banzai. Comes w .030. .040. .060. I first installed it w .040. Smoke way less. Put in .030 smoked less. I drove car to burn off residual oil and no smoke on cold start today. Yeah . im going to up the size of restrictor and cold start tmrw see what i get. The .030 seems small. Anyone k ow if this will harm turbo?
Thanks for all previous replies

Aaron Cake

iTrader: (1)

Yes, you NEED an oil restrictor for a GT40R.

A little oil in the compressor outlet isn't unusual.

E85 needs to run richer ratios on cold start, which can cause some smoke. The fact your oil smells of fuel indicates the car is running richer than it should. Absolutely a cause for smoke.

What are your AFRs at cold start and for the first few minutes?

For all those people suggesting compression checks: Compression has nothing to do with smoke!.

johnrx2

Well the smoke appears to b gone now did a cold start no oil smoke at all. It was pretty bad beforeuntill driven. Its a little rich. Afr stays around 11.6 to 12.4. Thats where it idles best w out bouncing . its a gt 40 non ball bearing. Is .030 safe?

Aaron Cake

iTrader: (1)

0.030 is fairly standard, so it's safe in my experience.

Often I make my own restrictors by soldering a fitting solid then drilling progressively larger holes until the smoke starts. Then resolder/braze and redrill the last size previous to the smoker.