VAXHeadroom

(OK, i did a bit of a search on this and can't find anything, so here's a new thread.)
Whenever I rev up to 5K and hold the RPM there, this car starts smokin like crazy! I mean like James Bond smoke screen thick. Any ideas? 2 other tidbits: 1) until the car warms up, the fast idle will pulse (oscillate) 2) the first time I rev above 4.5K and up shift, I get a blast of smoke out the back (after a cold start). I'm assuming it's some kind of vaccum problem, but if anyone has any ideas where to start debugging this I'd appreciate it!

Emory

Alex6969

what color is the smoke?
does it smoke when the motor is cold?

these cars smoke when they're cold. so i drive it gentaly (shifting under 3.5) until it warms up.

VAXHeadroom

Yep. That helps when it's cold, but the 5K+ thing smokes ALL the time. I'm guessing it's just burning rich (not oil), but that's purely a guess...

1SWEET7

iTrader: (1)

I believe blue smoke is good smoke and white is bad.

AcidAngel7477

iTrader: (16)

crap mine does this too....

gbowers

Your oil control rings are shot if you hold rev at 5-6K for 30 seconds and get alot of exhaust smoke. You must be burning more oil than normal.

orangegarage

Hello? got any expirence with RX7s at all? Dudes, its time to replace the motor, bad apex seals. You can try the water or ATF treatment to loosen up the carbon,(search the archives) but that only works some times. (OH yeah, to the last idiot that replied, THERE ARE NO OIL RINGS!!!!!!!!!!!!!!!)

gbowers

Rotary engine NA has oil control rings that seal rotors to Eshaft.

Your oil control rings are shot if you hold rev at 5-6K for 30 seconds and get alot of exhaust smoke. You must be burning more oil than normal.

Needa13b

What color is your smoke?

Blue = Oil
White = Coolant
Black = Unburned Hydro-Carbons

Your car shouldn't smoke anything:
-But it does burn oil. It shouldn't be excessive, nor should you ever really see it.
-White smoke means you're going to need a rebuild soon. Your coolant seal broke and is leaking coolant into your combustion chamber. If it's a small leak, it will go away when your engine warms up. But it will just get worse.
-Black means you need to tune your EFI, or fix a problem with your combustion or your catalytic converters. Black smoke could mean many things. So you need to figure out why you are throwing out unused gas from your tailpipe.

VAXHeadroom

It's blue. Yep, it does use more oil than normal - 1 qt about every 300 miles. Guess I start a 'rebuild the motor' jar at the house huh?

Thanks for the info all!

Needa13b

Just for comparison, I need 1 qt. every 1000-3000 miles, depending on driving of course.

Nick_d_TII

iTrader: (6)

You obviously have NO Idea what your talking about! There are too Oil Rings, but they're called Oil Control Rings! APEX SEALS!? WTF are you thinking? Apex Seals have nothing to do with smoking! They're for compression! Any smoking is coming from bad oil control rings leaking oil into the combustion chamber, or water getting in there from bad housing O-rings, and you would notice the coolant missing.

Although since it is NA its probably oil control rings as stated already.

But you, orangegarage, need to learn some stuff about these motors before you go shouting and giving bad/poor/stupid/dumb/ignorent advice to ANYONE!!! You don't need to replace the motor either, JUST REBUILD IT, WHICH YOU HAVE NEVER DONE!!!

gbowers

Nick, thanks for your support of my previous diagnois of bad oil control rings and I guess we know who the idiot is now - orangegarage.

gbowers

Please update status of your FC NA engine as my 1988 FC has same problems.

C.A.R

I dont know a lot about the rotary yet... I am learning though... The last 7 I had was bought smoking... Well... It would not start without being floored... When it did start it smoked like crazy... I could not let it drop below 3k rpm or it would die... It smelled like burning sugar and pepper gas... I finally leaned out the door of the car with the throttle depressed and looked under the car... That is when I realized my cat was glowing orange and was smoking terribly... I pulled it off and it ran great... it was loud as all get out... I put it back on and it blew the apex seals... Not that this is your problem, but you may look just to make sure...

VAXHeadroom

You're problem was a clogged catylitic converter!

MY problem (original thread creator!) is shot oil control rings. My mechanic recommended a product called "NoSmoke" which, while it won't fix the problem, won't look as bad!!

gear_grinder

iTrader: (4)

DUDE! does any one know that rx7s have oil injectors. there suposta kick on at higher rpm to prevent damge to vital engine parts at high rpm, so if the exhaust has few/no smog parts then it should smoke. why does every one asume it the oil control rings GOSH.

alexdimen

iTrader: (13)

Is this thread entitled: "idiots, please respond here"? jesus christ!!!



1. you're a fool, all mazda rotary engines have and require oil control rings. please shut up if you're going to talk out of your ***.


2. the condition of apex seals has no direct effect on smoking/emissions

3. wrong, the oil control rings do not seal the rotor to the eccentric shaft, they make a seal between the sides of the rotor and the iron side housings.

4. oil injectors, at any point in their stock operation, do not allow enough oil into the combustion area to create smoke. to answer your question, everyone assumes oil rings because oil injectors are not causing the problem.

to the original poster: it sounds like you have a major failure somewhere if you're using that much oil. oil control rings are the only thing that can cause that much oil to be burned off. otherwise, you would have to be leaking that much out externally.

mikaz

more incorrect information. they don't "kick on" at high RPMs. They are active all the time. And they also don't give out enough oil to see much, if any visable smoke.

Bottom line, if it's smoking blue, then yes, it's most likely the oil control rings.

Close this thread before somone looses an eye.

spot_skater

gbowers hit the nail right on the head. As did needa13b, with the smoke color explanation. AND not to mention Nick, telling off the guy whose giving his wrong opinion.

The only way to fix the oil control rings are to do a complete overhaul/rebuild. Mine did this for about a year. Man, it was fun sitting in traffic, and when some clown behind me would get too close for comfort, snap the throttle to ~6k, blast some smoke and a few flames at em.

Then it blew up.

And orangegarage, shut the **** up and do some research before you start spreading false information. Clearly you have no idea what you're talking about.

James

TehMonkay

iTrader: (-1)

I think the all caps GOSH was a sign of sarcasm, or at least I hope.

Also that no smoke stuff may kill your omp, lucas stuff killed someone i knows OMP in his S4. Most of that stuff is designed for piston engines and has a high concentration of lead in it to fill the grooves worn out of the block by the piston rings. It some have chemicals that cause the rubber valve stem seals to swell and prevent leakage. I don't think either would be good for a rotary.

jm93rx7

iTrader: (7)

This is mine when the oil control rings went bad. It was going through quite a bit of oil and i tried that stop smoke also and it didnt work for me. http://video.google.com/videoplay?d...379344882745239

My5ABaby

iTrader: (7)

So you're telling me a low compression engine has the same emissions output as a high compression engine?

Therex71

Alright, so i know NOTHING about the rotary engine, cept that i hate driving a non-rotary! Anyway, if you think smoking at 5K is bad...come hang out with my baby and me!! All you have to do to get a James Bond smoke screen for mine is turn it on!! Now, who wants to deal with THAT? My question is.....rebuild, or forget it and get a new engine?

darktritium

This is ridiculous. First of all, when is the last time you checked the timing? Everyone here is so anxious to say it's this and that without thinking about it. Just two things, check the timing and do a compression test. After that, you can troubleshoot from there. Also, please tell me you aren't flooring it or holding it at 5000 RPMs when the engine is still cold. (Within roughly 10 minutes of starting the car.)