oil on spark plugs of new engine - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 10-25-2010, 12:34 AM
BlenderHead's Avatar
Registered User
 
Join Date: Oct 2010
Location: Holden, MA
Posts: 27
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
oil on spark plugs of new engine

my 350 chevy small block was recently rebuilt (less than 100 miles on it) and there is quite a bit of oil on the spark plugs, especially on the threads of the spark plugs. So oil is somehow getting into the combustion chamber, but I'm not sure if it's the valve seals or the piston rings. There is also some carbon build-up on the end of the plug. Not sure if the carbon and oil are related.

The repair manual said that oil on spark plugs can sometimes be found on new or newly rebuilt engines before full oil control has been established?? I'm not sure what that means. Could it be that I didn't break-in the engine properly?

Thanks to anyone who can help with this.
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 10-25-2010, 01:46 AM
F-BIRD'88's Avatar
Yada Yada Yada
 
Last photo:
Join Date: Oct 2005
Location: Ontario, Canada
Posts: 9,181
Wiki Edits: 0

Thanks: 2
Thanked 291 Times in 288 Posts
Either the intake manifold gasket is sucking in oil or the PCV valve is sucking in oil (caused by a lack of PCV breather baffling in the valve cover) or the valve covers are leaking oil down on the spark plugs.
Yes that oil can migrate thru the spark plug threads and get into the motor.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 10-25-2010, 03:02 AM
BlenderHead's Avatar
Registered User
 
Join Date: Oct 2010
Location: Holden, MA
Posts: 27
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by F-BIRD'88
Either the intake manifold gasket is sucking in oil or the PCV valve is sucking in oil (caused by a lack of PCV breather baffling in the valve cover) or the valve covers are leaking oil down on the spark plugs.
Yes that oil can migrate thru the spark plug threads and get into the motor.
thanks for your reply. I do have the baffle in the valve cover under the pcv valve, the valve cover gaskets are not leaking, I guess i could check to see if the intake manifold gasket is leaking internally, but I'd really rather not take that off if I don't have to.
Just wondering... why don't you think it might be the valve seals or piston rings? is it because they are new and should not be leaking, cause that's what I think.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 10-25-2010, 03:17 AM
F-BIRD'88's Avatar
Yada Yada Yada
 
Last photo:
Join Date: Oct 2005
Location: Ontario, Canada
Posts: 9,181
Wiki Edits: 0

Thanks: 2
Thanked 291 Times in 288 Posts
The faults I listed are the most common cause of oil consumption/smoking exhaust/oiled plugs on new engine installs.

Check the intake manifold for vacuum leaks. Check the PCV hose for oil.
New rings do not smoke. Unless they were installed upside down or are broke.
Or the motor suffered severe piston ring cylinder wall fuel wash and scuffing from carb flooding on inital start up.
Missing intake valve seals is a possibility.
Smell the oil on the dip stick. Does it smell like gas? Is the oil in the pan now overfull? fuel in oil.

Most of the pretty aftermarket valve covers PCV baffling design "sucks"

Once you have found and correct the oil issue, a few good WOT power runs will seat the piston rings.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 10-25-2010, 04:16 AM
BlenderHead's Avatar
Registered User
 
Join Date: Oct 2010
Location: Holden, MA
Posts: 27
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by F-BIRD'88
The faults I listed are the most common cause of oil consumption/smoking exhaust/oiled plugs on new engine installs.

Check the intake manifold for vacuum leaks. Check the PCV hose for oil.
New rings do not smoke. Unless they were installed upside down or are broke.
Or the motor suffered severe piston ring cylinder wall fuel wash and scuffing from carb flooding on inital start up.
Missing intake valve seals is a possibility.
Smell the oil on the dip stick. Does it smell like gas? Is the oil in the pan now overfull? fuel in oil.

Most of the pretty aftermarket valve covers PCV baffling design "sucks"

Once you have found and correct the oil issue, a few good WOT power runs will seat the piston rings.

ok, cool. i'll check that stuff.... thanks.
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Engine Break-in Oil Psi HELP!!!!! eball Engine 29 02-21-2009 06:26 AM
Anyone have a guide on how to gap spark plugs on custom engine? timothy9972 Engine 14 08-20-2007 07:47 PM
Oil filter Super Magnets? Jag Daddy Engine 59 02-01-2006 07:36 PM
Spark Plugs Are Light Grey/whits And Their Is Oil On The Threads 70SPORT Engine 1 05-26-2004 12:25 PM
Spark Plugs Are Light Grey/whits And Their Is Oil On The Threads 70SPORT Engine 1 05-26-2004 06:56 AM


All times are GMT -6. The time now is 11:38 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.