Smoke on boost, Anybody experience this? - Page 2 - Rennlist - Porsche Discussion Forums

Notices

Smoke on boost, Anybody experience this?

Reply

Old 06-12-2018, 06:38 PM
  #16  
GPA951s
Addict
Rennlist Member
Thread Starter
 
GPA951s's Avatar
 
Join Date: Dec 2016
Location: Outskirts of Buffalo NY
Posts: 392
Default

Sorry for the confusion, All my engine building is done in my friends shop that is all american..Anyhow it comes out to about 2.7L Valve Stems, Seats, and the valves themselves are all brand new and perfect.. I am sure of that.. Going to check out the Turbo then Re-Route AOS.
BTW The Can was vented to atmosphere and NOT back into the inlet of the turbo...
GPA951s is offline  
Reply With Quote
Old 06-13-2018, 03:38 PM
  #17  
bw993
Addict
Rennlist Member
 
Join Date: Feb 2005
Location: San Diego
Posts: 819
Default

Let us know if routing the AOS return line to the front of your turbo solves the problem.
bw993 is offline  
Reply With Quote
Old 06-14-2018, 12:06 PM
  #18  
cruise98
Addict
Rennlist Member
 
cruise98's Avatar
 
Join Date: Jan 2002
Location: Abqaiq Saudi Arabia
Posts: 1,538
Default

I could be wrong, but this is exactly what happened to me. But, both of mine were Garret hybrids with the single shaft seals. If the K-26 was properly done, that one should not smoke. What did the first turbo look like when you took it off? Oil in the turbine or the compressor side?
cruise98 is offline  
Reply With Quote
Old 06-15-2018, 09:48 PM
  #19  
GPA951s
Addict
Rennlist Member
Thread Starter
 
GPA951s's Avatar
 
Join Date: Dec 2016
Location: Outskirts of Buffalo NY
Posts: 392
Default

Originally Posted by cruise98 View Post
I could be wrong, but this is exactly what happened to me. But, both of mine were Garret hybrids with the single shaft seals. If the K-26 was properly done, that one should not smoke. What did the first turbo look like when you took it off? Oil in the turbine or the compressor side?

Not Really, I will have the Turbo checked out but there has been a new Development.... MY AOS had a Hole in it big enough to put a softball in... Holy Cow... It looks like there was a blowtorch inside it. I took the intake off and noticed "Plastic Slag" on the outside of it, looked a little deeper and Wow! Tried to take pics of it but they really did turn out crappy. When I get it removed I will post a pic... Everyone I have talked to says It does happen from time to time but nobody can tell me why. True it is 30 year old plastic.. but why the "blowtorch" effect? Hmmmmmmmm
GPA951s is offline  
Reply With Quote
Old 06-17-2018, 10:25 AM
  #20  
GPA951s
Addict
Rennlist Member
Thread Starter
 
GPA951s's Avatar
 
Join Date: Dec 2016
Location: Outskirts of Buffalo NY
Posts: 392
Default

Ok So I was taking the turbo off and noticed this.......


So a Rummage around my parts bin and a little "upgrade" so this will never happen again...
GPA951s is offline  
Reply With Quote
Old 06-17-2018, 10:51 AM
  #21  
Humboldtgrin
Addict
Rennlist Member
 
Humboldtgrin's Avatar
 
Join Date: Jun 2014
Location: NORTHERN CALIFORNIA
Posts: 1,926
Default

That’s a dirty hole!
Humboldtgrin is offline  
Reply With Quote
Old 06-17-2018, 11:35 AM
  #22  
Dan Martinic
Addict
Rennlist Member
 
Dan Martinic's Avatar
 
Join Date: Aug 2017
Location: Toronto, Ontario, Canada
Posts: 777
Default

What the ???

Crazy! Like there was a brief fire there or something.

Love the look of your blue 951 with the checkers
Dan Martinic is offline  
Reply With Quote
Old 06-17-2018, 12:10 PM
  #23  
Tom M'Guinn
Addict
Rennlist Member

 
Tom M'Guinn's Avatar
 
Join Date: Jan 2002
Location: Just CA Now :)
Posts: 10,465
Default

Were you not running the factory/metal heat shield?
Tom M'Guinn is online now  
Reply With Quote
Old 06-17-2018, 12:37 PM
  #24  
GPA951s
Addict
Rennlist Member
Thread Starter
 
GPA951s's Avatar
 
Join Date: Dec 2016
Location: Outskirts of Buffalo NY
Posts: 392
Default

Originally Posted by Tom M'Guinn View Post
Were you not running the factory/metal heat shield?
Yes all heat shields were in place, additionally the downpipe was wrapped with header wrap..... But I did find one of the Allen head screws that held the 3" Down pipe in place loosened up. the weird thing is that its pretty far away from where it melted the plastic. The whole 3" Down pipe is going away, with the stock turbo there is no need for it. I dont see any advantage in it, its just a pain in the *** to get in and out the flange is just ridiculous big.
I found an original down pipe in my pile of parts and I am modifying it to transition from the original size to 4" right after the starter...
GPA951s is offline  
Reply With Quote
Old 06-17-2018, 01:03 PM
  #25  
Tom M'Guinn
Addict
Rennlist Member

 
Tom M'Guinn's Avatar
 
Join Date: Jan 2002
Location: Just CA Now :)
Posts: 10,465
Default

Originally Posted by GPA951s View Post
Yes all heat shields were in place, additionally the downpipe was wrapped with header wrap..... But I did find one of the Allen head screws that held the 3" Down pipe in place loosened up. the weird thing is that its pretty far away from where it melted the plastic. The whole 3" Down pipe is going away, with the stock turbo there is no need for it. I dont see any advantage in it, its just a pain in the *** to get in and out the flange is just ridiculous big.
I found an original down pipe in my pile of parts and I am modifying it to transition from the original size to 4" right after the starter...
Weird. Your motor is telling you something, I'm just not sure what. Those 3" downpipes can touch the heatshield, which would transfer a lot more heat I suppose. But if that doesn't fix it, you shouldn't need all that extra shielding to prevent the AOS from melting. Do you have an exhaust temp probe? Laust's probe and Zeitronix work great and offer lots of data here for comparison. If the exhaust is overly hot, do you have enough timing advance, or too much back pressure? There is a connecting hose/pipe between the turbo oil drain and the AOS and I'm wondering if that got damaged and is part of your oiling/smoke issue?
Tom M'Guinn is online now  
Reply With Quote
Old 06-17-2018, 01:37 PM
  #26  
GPA951s
Addict
Rennlist Member
Thread Starter
 
GPA951s's Avatar
 
Join Date: Dec 2016
Location: Outskirts of Buffalo NY
Posts: 392
Default

I Just had the car Dyno-tuned, and I am positive timing/and backpressure is good, Its (was a 3" to 4" all the way back straight pipe) Im Pretty sure it was that stupid allen Screw coming loose. Im going to put a different oil feed line on the turbo with a built in filter from tims turbos. I will check the oil Return line.. So I am Curious,, When you remove the oil feed line from the top of the turbo I noticed that there was oil sitting there and not draining. Is that normal? OR should the oil drain down into the pan through the turbo?
GPA951s is offline  
Reply With Quote
Old 06-17-2018, 04:06 PM
  #27  
NCLA951
Addict
Rennlist Member
 
Join Date: Sep 2015
Location: Los Angeles
Posts: 443
Default

I just discovered my AOS was heading that way when I pulled my motor. I had heat sheild on, but no wrap on 3ö downpipe.
NCLA951 is offline  
Reply With Quote
Old 06-17-2018, 09:46 PM
  #28  
Noahs944
Addict
Rennlist Member
 
Noahs944's Avatar
 
Join Date: May 2013
Location: Calgary, Alberta, Canada
Posts: 2,892
Default

Originally Posted by GPA951s View Post
I Just had the car Dyno-tuned, and I am positive timing/and backpressure is good, Its (was a 3" to 4" all the way back straight pipe) Im Pretty sure it was that stupid allen Screw coming loose. Im going to put a different oil feed line on the turbo with a built in filter from tims turbos. I will check the oil Return line.. So I am Curious,, When you remove the oil feed line from the top of the turbo I noticed that there was oil sitting there and not draining. Is that normal? OR should the oil drain down into the pan through the turbo?
Oil should sit in the hole but when you spin the impeller (compressor/cold side wheel) quickly for like 30-60 seconds then the oil should lower then exit into the drain. That is normal for a brand new turbo.
Noahs944 is offline  
Reply With Quote
Old 06-23-2018, 11:05 AM
  #29  
Noahs944
Addict
Rennlist Member
 
Noahs944's Avatar
 
Join Date: May 2013
Location: Calgary, Alberta, Canada
Posts: 2,892
Default

Edit on my last comment. 2 days ago we replaced a turbo with a rebuilt unit on a skid steer. The oil wouldn't go down by spinning (or at least I got tired of trying). So... I guess different turbo bearings react differently. Most of my turbo replacement experience is on Cummins diesel engines & those ingest oil very easily.
Also, another thought is friction bearing vs roller bearing. I have no experience with roller bearing turbos, but have heard it will require a reduced amount of oil feed vs friction.
Noahs944 is offline  
Reply With Quote

Thread Tools
Search this Thread
Quick Reply: Smoke on boost, Anybody experience this?


Contact Us Advertising Cookie Policy Privacy Statement Terms of Service

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: