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-   -   When I rev my TII it does this...(pic inside) (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/when-i-rev-my-tii-does-pic-inside-692544/)

JasonS 09-28-07 05:09 PM

When I rev my TII it does this...(pic inside)
 
I just picked up this TII and although I love driving it, I'm not very familiar with the ins and outs of turbos, (no pun intended!)

I've noticed if I'm in the turbo hard and I let off and allow the motor to slow me down about 2 seconds later, smoke comes pouring out the exhaust. Today I found out if I rev it a bit it will begin to smoke as well. If I get on and off the throttle it REALLY smokes, so there seems to be more smoke as I lift off the throttle.

This is a S5 motor/turbo and there are some things that are rigged, so I'm not convinced the motor is shot, (although that is very possible.)

It starts up okay, idles very well and doesn't smoke. It seems to pull pretty hard as well.

All emissions were removed prior to my purchase.

I'm just looking for ideas.

http://i91.photobucket.com/albums/k2...s/DSC00368.jpg

Jpk3200 09-28-07 05:16 PM

Bad oil control O-rings?

phoenix7 09-28-07 05:27 PM

can't tell if it's white smoke or not. Bad coolant seals?only if it's white smoke.

If it's dark smoke it might be the turbo gaskets? or like it was posted above the oil control rings.

What color is it? does it do it when the car is turned on first thing in the morning?

TehMonkay 09-28-07 06:51 PM

Is there oil or oil stains on the downpipe to turbo flange, or in that area?

Looks just like my friends car with a blown turbo. I like to call him the mosquito killer.

dean23 09-28-07 07:19 PM

looks like my car at idle some days.... damn break-in tune and a blown turbo :( ..

do you have the stock ECU still? my car used to do something like that wheni went in and out of boost due to it being really rich.

gtu'd 09-28-07 07:20 PM

Are you running it/revving it while it's cold or warm? Mine pours smoke when it's cold...

chatchie 09-28-07 08:03 PM

pop the line off the inlet of the intercooler and check for excessive oil.

JasonS 09-29-07 09:22 AM

I'll answer the questions I can:

Q: Can't tell if it's white smoke or not.
A: The smoke looks white, but it doesn't smell sweet. It smells like oil.

Q: If it's dark smoke it might be the turbo gaskets? or like it was posted above the oil control rings.
A: I wouldn't say it's dark.

Q: Does it do it when the car is turned on first thing in the morning
A: No smoke on start-up that I can tell, cold or hot.

Q: Is there oil or oil stains on the downpipe to turbo flange, or in that area?
A: I'll check at lunch today.

Q: Do you have the stock ECU still?
A: I was told it is the stock S4 ECU and again, this is a S5 motor/turbo

Q: Are you running it/revving it while it's cold or warm?
A: I'm revving it when it's warm. I am hitting redline, (stupid, I know, but it still shouldn't do this!) to get the smoke, but after the smoke I'm blipping the throttle.

Q: Pop the line off the inlet of the intercooler and check for excessive oil.
A: I'll do this at lunch as well.

Thanks!!

hurleysurf24 09-29-07 11:21 AM

compression test it ?

iox106 09-29-07 11:51 AM

Sounds like a coolant seal to me. I had the same issues wit a my car not to long ago.

http://www.rotaryresurrection.com/2n...l_failure.html

JasonS 09-29-07 12:06 PM

I just checked the inlet to the intercooler, (the only large hose on the front passenger side of intercooler) and it does have a thin film of oil in there.

I also looked all around the turbo , the best I could and see no leaks, or stains.

I'll fill it with coolant and crank it over cold w/out the egi fuse and see what happens.

Again...it is not difficult to start and it doesn't smoke when it is started.

~Jason

markdman 09-29-07 01:21 PM

sounds like oil pushing past the bearins when the pressure rises. turbo rebuild time

JasonS 09-29-07 01:39 PM

I don't think I would mind that so much. I'll need to do a search to see how difficult a turbo rebuild is.

I'll keep you guys posted.

Thanks again!
~Jason

JasonS 09-29-07 03:12 PM

Okay, I have the TII hooked up to my piston engine tester and I'm waiting for my wife to come home so she can floor the thing and turn it over a few times.

I took a few pictures while I was waiting as I'm a man full of questions!

Picture 1: Do these plugs look okay? They are the lower plugs from the front/rear rotors and the one on the right as you look at the picture is from the front.
http://i91.photobucket.com/albums/k2...DSC00368-1.jpg

Picture 2: What in the world is this fitting for?! It's pushed into the rigged up duct work to the turbo which I plan on re-doing.
http://i91.photobucket.com/albums/k2...s/DSC00369.jpg

Picture 3: What is this??!! Someone must have worked at Home Depot and swiped a few items from the plumbing dept!! I think the round black piece with red hose is the bov, (did I mention I don't know turbos?!), but what is the brass fitting at the end of the line?
http://i91.photobucket.com/albums/k2...s/DSC00370.jpg

Picture 4: I searched around the turbo for leaks and found none. Can anyone tell if this is an S5 turbo?
http://i91.photobucket.com/albums/k2...s/DSC00371.jpg

Picture 5: What's the round dirty silver item in the middle of the picture below the turbo duct work?
http://i91.photobucket.com/albums/k2...s/DSC00373.jpg

Picture 6 & 7: Are the following pictures a tell tale sign of a S5 TII motor? I just want to be sure.
http://i91.photobucket.com/albums/k2...s/DSC00376.jpg

http://i91.photobucket.com/albums/k2...s/DSC00375.jpg

Oooooo I hear my wife pulling up, so time for a compression test.

staticguitar313 09-29-07 03:24 PM

make sure your premixing! i see the oil metering pump blocked off!
autozone sells custom intake piping and couplings, mine used to look as bad as yours

SirCygnus 09-29-07 03:38 PM

o shit your not premixing!! and if you are, then smoke would be seen.

if not, put friggin two stroke oil in your gas tank.

toplessFC3Sman 09-29-07 03:38 PM

I cant tell about the short-block, but the manifolds, water pump and front cover are definately S4, and you've got the OMP blocked off (so i hope you've been pre-mixing!)

Picture 1: The plugs dont look terrible, clean off the tip and see how sharp the edges on the center electrode and the blocks around it are. The sharper the better.
Picture 2: No idea what that thing is, but if its open to atmosphere, it's gonna make the computer think you're sucking less air than you actually are (since less than the full amount is going thru the afm), and will make you run a little lean. Cap it of figure out whats supposed to be on it.
Picture 3: The black plastic thing near the home-depot mess is your BOV (recirculation valve, but its essentially the same thing) Its supposed to vent back into the intake between the AFM and the turbo inlet, but it doesnt seem to be in that picture. I have no idea about the brass fitting tho.
Picture 4: From that angle of the turbo, I cant really tell whether its S4 or S5... but I think part of the larger wastegate and turbine housing would be visible if it were S5, so if i had to guess id say S4
Picture 5:The round silver dirty thing is your wastegate. If the long rod coming out of it is straight, then the turbo is S4. If the rod has a kink in it, its an S5
Pictures 6 and 7: Metal thermostat housing, place to mount the OMP on the front cover (but is blocked off) mean its an S4 water pump and front cover at least, I dont know if the irons, rotors, rotor housings etc are S4 or S5


If you have oil in the intercooler, the smoke is most likely one of two things. Its either the oil seal on the compressor side of the turbo, or the guy who did the emissions removal did a shitty job. Check the crankcase vent tubes coming off of your oil fill neck and center housing (right below the oil fill neck). Trace where these tubes go to. One should go to the PCV valve (a black plastic disc looking thing with 2 nipples coming off one side, 1 nipple off the other), and then to the intake pre-turbo, and the other should go back to a T with the charcoal canister, and then to the intake. If not, you could be sucking oil straight out of the crank case and thru your turbo, especially at high loads or high RPMs.

Also, the BAC valve (the valve on the pass side of the engine, mounted to the UIM), should have coolant hoses connected to it to keep it from freezing up, siezing etc. You can run a line from the nipple on the back of the water pump under the alt to the front nipple on the BAC, and then from the rear nipple on the BAC to the nipple sticking straight up on the pass side of the rear iron.

JasonS 09-29-07 04:37 PM

Okay, I'm back! I'll have to read that last post several times to let it all sink it! Thank you!!

I am premixing!! Last time I put 8oz of 2 cycle oil to my 10 gallons of fuel.

On to the compression test, (this was fun!!)

As a point of reference here's my compression tester:
http://i91.photobucket.com/albums/k2...sionTester.jpg

Front Rotor:
Valve open on tester I get three even pulses at 75 PSI
Valve closed on tester compression builds to 80-85 PSI

Rear Rotor:
Valve open on tester I get three even pulses at 60 PSI
Valve closed on tester compression builds to 75 PSI

I really appreciate the input from you all!!

Time to take the wife and kids out to eat!!

1SxyRXy 09-29-07 04:39 PM

sounds like you need a rebuild. u test at WOT while cranking?

toplessFC3Sman 09-29-07 05:17 PM

3 even pulses per rotor, so the engine may be a bit tired and worn, but its not blown and wouldn't be causing the smoke you're seeing. Plus with the variability of cranking speed, connections and the response time of the compression tester, the engine may be much better than the numbers posted would have you believe.

JasonS 09-29-07 07:24 PM

Q: Check the crankcase vent tubes coming off of your oil fill neck and center housing (right below the oil fill neck). Trace where these tubes go to. One should go to the PCV valve (a black plastic disc looking thing with 2 nipples coming off one side, 1 nipple off the other), and then to the intake pre-turbo, and the other should go back to a T with the charcoal canister, and then to the intake. If not, you could be sucking oil straight out of the crank case and thru your turbo, especially at high loads or high RPMs.

A: I checked this and the fitting on the oil fill neck is open. The other fitting is kind of tucked behind there in the intermediate housing and it has a rubber cap on it that is clamped off. Also there is no charcoal canister on this car, so I'm not sure what I will do next.

I think the #s are pretty good from what I've seen on this board. I think it's an issue with the emissions being removed and a few things that are rigged.

I'm not sure if it means anything, but I did launch hard today and blow the hose off from the brake booster. My brakes got real hard, so I pulled over and pushed the hose back on! :)

eriksseven 09-29-07 09:26 PM

Yo, your plugs look like they've been seeing a little bit of oil... ;) Could be an indication that it's bad oil-control rings/seals as opposed to bad turbo oil-seals...

That silver nipple on your turbo intake ducting is for crank-case ventilation. You can route a hose from your oil filler neck ventilation nipple to this silver nipple to help recirculate/vent your crankcase in the same way it's done stock. If you don't want to route a hose, then cap it, because it is allowing unmetered air to be sucked in.

That brass fitting is acting as a one-way check valve for your stock blow-off valve that is no longer being recirculated into stock turbo inlet duct. Without this brass fitting, your stock BOV would be acting as a large vaccum leak.

60-85psi compression is not good... 100psi+ would be good compression.

Your engine looks like it is an s5, based on the front-cover.

JasonS 09-29-07 09:37 PM

"60-85psi compression is not good... 100psi+ would be good compression."

I had a S5 convertible tested at Mazda a couple months back and it was 85-85-87 on the front and rear rotor and the certified rotary specialist said that was excellent. Mazda spec is 85 as well, so where's this 100+ psi coming from?

Thanks for the other help though. I really do appreciate it.

SirCygnus 09-29-07 09:58 PM

dont worry about compression unless it gets into the 70's.

texFCturboII 09-29-07 10:01 PM


Originally Posted by eriksseven (Post 7381746)
.......Your engine looks like it is an s5, based on the front-cover.

If it was an s5 with his OMP removed he wouldn'y be posting about white smoke, he'd be posting "Why does my car lose power after 10minutes of driving?" I think that's an s4 engine.


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