2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

Blue smoke at redline shifts...but never any other time?

Thread Tools
 
Search this Thread
 
Old Feb 24, 2009 | 01:46 PM
  #1  
jjwalker's Avatar
Thread Starter
MECP Certified Installer
Tenured Member 05 Years
 
Joined: Feb 2009
Posts: 3,176
Likes: 3
From: Mesquite, TX-DFW
Blue smoke at redline shifts...but never any other time?

I did my research on this is and my reasearch would indicate it is a bad oil seal, BUT things don't all add up.

If I shift at 6500 no smok at all. Never smokes at idle hot or cold. Never smokes at any time with the exception of 7300rpm + shifting. Above 7300rpm, it puffs a small blue cloud.

It is always either a small cloud of blue smoke or absolutely nothing at all. It's a head scratcher.

My car also doesn't consume abnormal amounts of oil. It only consumes maybe a quater of a quart if not less every 1000 miles and I have to drive it hard to do that. My thought is that the oil seal leaks slightly only at extremely high rpm, but never at any other time. Weird.

Any ideas?
Reply
Old Feb 24, 2009 | 02:20 PM
  #2  
eage8's Avatar
1308ccs of awesome
Tenured Member: 20 Years
iTrader: (9)
 
Joined: Sep 2003
Posts: 6,189
Likes: 18
From: Woodbine, MD
S4 or S5?

NA or turbo?

are you premixing?
Reply
Old Feb 24, 2009 | 03:05 PM
  #3  
jjwalker's Avatar
Thread Starter
MECP Certified Installer
Tenured Member 05 Years
 
Joined: Feb 2009
Posts: 3,176
Likes: 3
From: Mesquite, TX-DFW
It is a 1990 Vert, stock NA motor. I put a slight amount of premix in (about 2 ounces and filled up).
Reply
Old Feb 25, 2009 | 12:51 AM
  #4  
jjwalker's Avatar
Thread Starter
MECP Certified Installer
Tenured Member 05 Years
 
Joined: Feb 2009
Posts: 3,176
Likes: 3
From: Mesquite, TX-DFW
Nothing eh?
Reply
Old Feb 25, 2009 | 12:54 AM
  #5  
cmanns's Avatar
Smoke moar
Tenured Member 05 Years
 
Joined: Aug 2006
Posts: 2,530
Likes: 1
From: The yay, California
Extra oil injectors kick in somewhere around 5500 rpm or so starts to really show around 7k rpm

If you just rev it quickly do you see smoke? If you rev it around 6k and pop it over 7.5k a few times (holding it around 6k) do you see plumes?

It's exactly what I've always had, no smoke otherwise I could be wrong that it's the oil injectors but I'm pretty sure.

It's nice taking it all the way to 8k rpm and leaving a trail of blue smoke at the ******* behind you hehe

Hope that helps m8
Reply
Old Feb 25, 2009 | 02:51 AM
  #6  
RotaryEvolution's Avatar
Sharp Claws
Tenured Member 15 Years
iTrader: (30)
 
Joined: Oct 2003
Posts: 5,107
Likes: 50
From: Central Florida
bad oil seals, as they progressively get worse it will smoke at lower and lower RPMs.

try thicker oil, 20w-50 for now to get by.
Reply
Old Feb 25, 2009 | 05:49 AM
  #7  
cmanns's Avatar
Smoke moar
Tenured Member 05 Years
 
Joined: Aug 2006
Posts: 2,530
Likes: 1
From: The yay, California
^

seriously? I was told it was other injectors kicking in for the high rpms O.O
Reply
Old Feb 25, 2009 | 08:40 AM
  #8  
jjwalker's Avatar
Thread Starter
MECP Certified Installer
Tenured Member 05 Years
 
Joined: Feb 2009
Posts: 3,176
Likes: 3
From: Mesquite, TX-DFW
Ouch, that sucks.

I know my way around a reciprocating engine in and out, but a whole lot about rotaries. Is the same scenario as a piston engine, meaning it could probably last a while and just slowly get progressively worse? That is of course beside a catastrophic seal failure happening.
Reply
Old Feb 25, 2009 | 08:48 AM
  #9  
VAXHeadroom's Avatar
commit(rnd()&sense-acts)
Tenured Member 15 Years
 
Joined: Feb 2005
Posts: 378
Likes: 0
From: Lutherville MD
Originally Posted by Karack
bad oil seals, as they progressively get worse it will smoke at lower and lower RPMs.
try thicker oil, 20w-50 for now to get by.
I agree with this advice. My 88 N/A 'vert has this issue and it has progressed down from 6500 to 5500 (187K miles). I've tried MANY different oil viscosities and for me 10W30 produces the least smoke. YMMV Go with what works, live with it for now (it won't hurt anything in the engine) and save your nickles for a rebuild. The progression from 6500 down to 5500 happened across about 25,000 miles (I was driving it 100 miles a day), so my experience was that this degeneration happens kind of slowly. I now have a blown coolant seal, but the opinion is that these are not related except for the fact that I've got 187K miles on the original motor.
I also found that it only happens 1) when shifting (the quicker I shift, the less smoke I get), and when holding the engine RPM at or above the 'oil smoke point', i.e. if I hold it at 5000, no smoke. If I hold it at 5,500, I'm James Bond...which I've used once or twice on the road when being tailgated by some idiot
Good Luck!
Reply
Old Feb 25, 2009 | 09:05 AM
  #10  
jjwalker's Avatar
Thread Starter
MECP Certified Installer
Tenured Member 05 Years
 
Joined: Feb 2009
Posts: 3,176
Likes: 3
From: Mesquite, TX-DFW
Well, I was thinking of doing 20w50 but all I can find is rotella. Is that okay?
Reply
Old Feb 25, 2009 | 09:15 AM
  #11  
jjwalker's Avatar
Thread Starter
MECP Certified Installer
Tenured Member 05 Years
 
Joined: Feb 2009
Posts: 3,176
Likes: 3
From: Mesquite, TX-DFW
okay. And if I don't get smoke then what?

I'll try that after my "no BAC" cold startup test we are doing in another thread.
Reply
Old Feb 25, 2009 | 01:31 PM
  #12  
jjwalker's Avatar
Thread Starter
MECP Certified Installer
Tenured Member 05 Years
 
Joined: Feb 2009
Posts: 3,176
Likes: 3
From: Mesquite, TX-DFW
Alright, I had to go run some errands and I gave the car some hell and voila, no smoke. Now I am even more dumbfounded.

I am out to go do the 3500 RPM test right now.
Reply
Old Feb 25, 2009 | 02:07 PM
  #13  
EmbassyBlack's Avatar
Full Member
Tenured Member 10 Years
 
Joined: Jan 2008
Posts: 106
Likes: 0
From: Windsor ontario
im having the same type of problem.

in neutral or while driving if i rev it over 6500 rpm i get a cloud of blueish white smoke that comes out. when i first got my car and didnt know much about it a guy that supposedly know alot about rotaries told me to use synthetic and thats when it started. i went back to mineral oil and it still does that. btw i dont have cats so maybe thats a possible cause too
Reply
Old Feb 25, 2009 | 02:35 PM
  #14  
EmbassyBlack's Avatar
Full Member
Tenured Member 10 Years
 
Joined: Jan 2008
Posts: 106
Likes: 0
From: Windsor ontario
the motor came out of a car that had around 25k on it. Once i got the motor in i did a full tune up except for wires, that was April-May

btw OP lol sry to hijack your thread
Reply
Old Feb 25, 2009 | 02:38 PM
  #15  
EmbassyBlack's Avatar
Full Member
Tenured Member 10 Years
 
Joined: Jan 2008
Posts: 106
Likes: 0
From: Windsor ontario
the car that the motor came out of had around 25000kms on it, i did a full tune up except for ignition wires once i got the motor in which was around April-May.

btw OP lol sorry to hijack your thread
Reply
Old Feb 25, 2009 | 02:40 PM
  #16  
st1llet0's Avatar
Senior Member
Tenured Member 10 Years
iTrader: (2)
 
Joined: Feb 2007
Posts: 667
Likes: 0
From: KCMO
That happens to be as well, I've always thought it was the fuel injectors cutting way back when you let off the throttle, however the engine is still spinning, and creating a lot of vacuum, which I thought kept sucking oil from the oil injectors, and burning it all up. Does anyone with a blocked off omp running premix get these symptoms?
Reply
Old Feb 25, 2009 | 03:14 PM
  #17  
jjwalker's Avatar
Thread Starter
MECP Certified Installer
Tenured Member 05 Years
 
Joined: Feb 2009
Posts: 3,176
Likes: 3
From: Mesquite, TX-DFW
Nope, 3500rpm test for 30 seconds yields nothing.
Reply
Old Feb 25, 2009 | 05:18 PM
  #18  
RotaryEvolution's Avatar
Sharp Claws
Tenured Member 15 Years
iTrader: (30)
 
Joined: Oct 2003
Posts: 5,107
Likes: 50
From: Central Florida
wierd, i haven't seen results from a lighter weight oil reducing smoke but anything is possible, generally i always start out with lighter weight oil and move up from there. what happens is the oil control o-rings get squared off and brittle and can no longer hold oil pressure. at higher engine RPMs the oil seal carriers float around to the point that the oil can get past the seals, i suspect a lighter weight oil might be able to be wiped off before it can get past the side seals but it really is situational so different oils may yield different results. i haven't seen oil injectors cause excessive smoking before so i just doubt that is the cause.

if the oil seal o-rings begin to crack from age then the smoking will get progressively worse much quicker. my GXL smokes from startup until fully warmed up now due to cracked oil seals. cracked oil seal o-rings expand with heat and smoke when cold but seal up when warm, squared off brittle o-rings smoke at high RPMs and eventually get worse over time, both have similar results but at opposite ends of the RPM range.
Reply
Old Feb 25, 2009 | 09:16 PM
  #19  
GatorFC's Avatar
carbon footprint
 
Joined: Feb 2009
Posts: 70
Likes: 0
From: Florida
My car has done the same thing for as long as ive had it. When I shift above 6K or so RPM's I get one or two backfires and a small cloud of bluegrey smoke and a strong burnt oil smell. If i try this a second or third time, it makes little or no smoke at all. The car also does not have cats so this could be why.

A similar thing would happen when I would start it. It used to spew tons of smoke whenever i started it and it would rev up to 3K rpm cold cycle but It has gotten better since.
Reply
Old Feb 26, 2009 | 01:51 PM
  #20  
jjwalker's Avatar
Thread Starter
MECP Certified Installer
Tenured Member 05 Years
 
Joined: Feb 2009
Posts: 3,176
Likes: 3
From: Mesquite, TX-DFW
I think there was a puddle of seafoam still in my manifold because I did some extremely hard driving yesterday and no smoke, not even at redline.
Reply
Old Feb 27, 2009 | 11:28 AM
  #21  
jjwalker's Avatar
Thread Starter
MECP Certified Installer
Tenured Member 05 Years
 
Joined: Feb 2009
Posts: 3,176
Likes: 3
From: Mesquite, TX-DFW
I warmed it up and tried again this morning, still no smoke. I have 2 possible explanations...

1) Puddle of seafoam in the manifold froma week ago. It could have got stuck behind the VDI valve and decided the enter the motor when I floored it several days later.

2) Oil control ring got stuck temporarily.

I am betting on the first one though, it makes more sense.
Reply
Old Feb 27, 2009 | 11:34 AM
  #22  
cmanns's Avatar
Smoke moar
Tenured Member 05 Years
 
Joined: Aug 2006
Posts: 2,530
Likes: 1
From: The yay, California
Originally Posted by Karack
<snip>
awww that sucks, mine sends out a plume @ high rpms guess it's not good I rev past 8k
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
IB Cristina
West RX-7 Forum
0
Aug 20, 2015 05:46 PM
pzr2
General Rotary Tech Support
1
Aug 15, 2015 08:29 PM




All times are GMT -5. The time now is 07:51 AM.