Chevy/GMC 6.2L and 6.5L Discussion of Chevy and GMC Trucks with 6.2L and 6.5L Diesel Engines

86 6.2 smokes a lot and sputters under acceleration and at idle

Thread Tools
 
Search this Thread
 
  #1  
Old 06-14-2012, 09:01 PM
Joe Kapitany's Avatar
Newbie
Thread Starter
Join Date: Jun 2012
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default 86 6.2 smokes a lot and sputters under acceleration and at idle

got an 86 k5 with 6.2 and it starts really easy just runs reall choppy and puffs out quite a bit of white smoke and doesnt go away, havent checked the glow plugs or anything and its misses or sputters under moderate acceleration and high rpms had this truck a week and its my first diesel has 175k miles on it, any ideas?
 
  #2  
Old 06-15-2012, 02:31 AM
cviola2005's Avatar
Diesel Enthusiast
Join Date: Apr 2012
Location: Clarkrange, TN
Posts: 312
Received 18 Likes on 18 Posts
Default

i'd say the piston rings are worn out. mine runs good but white/blue smokes alot. Alot of blowby.
 
  #3  
Old 06-15-2012, 11:02 AM
Joe Kapitany's Avatar
Newbie
Thread Starter
Join Date: Jun 2012
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default

its not blue smoke, it smells like diesel but it might be a mix, what is blowby?
 
  #4  
Old 06-18-2012, 11:15 AM
cviola2005's Avatar
Diesel Enthusiast
Join Date: Apr 2012
Location: Clarkrange, TN
Posts: 312
Received 18 Likes on 18 Posts
Default

cylinder compression blowing by the piston rings into the crankcase.
 
  #5  
Old 06-18-2012, 06:13 PM
ebarresi5894's Avatar
Diesel Wrench
Join Date: May 2011
Location: Rehoboth, MA
Posts: 525
Received 12 Likes on 12 Posts
Default

could be leaky injectors, or a bad head gasket/head.

how much white smoke on start up?
 
  #6  
Old 06-19-2012, 04:48 PM
Joe Kapitany's Avatar
Newbie
Thread Starter
Join Date: Jun 2012
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default

it smokes quite a bit at startup but once it gets warmed up its not so bad but still does a little and it doesnt smell like coolant just like raw fuel. And the truck runs at about 150 F when its fully warmed up. i notice that is smokes mainly when i let off the throttle while driving and its got true dual exhaust and both sides smoke
 
  #7  
Old 06-19-2012, 09:06 PM
ebarresi5894's Avatar
Diesel Wrench
Join Date: May 2011
Location: Rehoboth, MA
Posts: 525
Received 12 Likes on 12 Posts
Default

sounds like a head gasket issue, how is the coolant? how is the oil?
 
  #8  
Old 06-19-2012, 09:25 PM
Joe Kapitany's Avatar
Newbie
Thread Starter
Join Date: Jun 2012
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default

the oil didnt have any water in it that i could tell when i changed it which was saturday and it doesnt leak or use any oil that i could tell. but i will check the coolant level tomorrow after duty if i get a chance

---AutoMerged DoublePost---

what about advancing the injection pump a little bit? not sure how this could have got out of time at all, i looked and the marks lined up but maybe the chain stretched. like i said im new to diesel and it comes out of both exhaust pipes so i hope both head gaskets arent bad
 

Last edited by Joe Kapitany; 06-19-2012 at 09:25 PM. Reason: Automerged Doublepost
  #9  
Old 06-20-2012, 05:49 PM
ebarresi5894's Avatar
Diesel Wrench
Join Date: May 2011
Location: Rehoboth, MA
Posts: 525
Received 12 Likes on 12 Posts
Default

if you have access or experience in trucks, you can do a compression test.

if not, bring it somewhere and have them do it.

or, take the glow plugs out and se if coolant pees out of the hole
 
  #10  
Old 06-27-2012, 02:03 AM
cviola2005's Avatar
Diesel Enthusiast
Join Date: Apr 2012
Location: Clarkrange, TN
Posts: 312
Received 18 Likes on 18 Posts
Default

my truck ran exactly the same as you describe yours runs. i advanced my injection pump timing and turned the fuel screw in a smidge and it has virtually quit smoking.a few puffs randomly as it idles and thats it
 




All times are GMT -5. The time now is 10:14 AM.