The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 12-23-2010, 04:33 PM   #1
screamin_c10
I dun gradjiated collij!!!
 
screamin_c10's Avatar
 
Join Date: Jan 2006
Location: St. Helens Oregon
Posts: 1,750
Unhappy Engine smoking, could use some ideas...

So I'm stumped.... My 307 is blowing blue smoke any rpm off idle. Here is some background to what I've done and steps I've taken thus far.

The engine is my '71 307 Flat top 4VR pistons, originally had 74cc 1.74/1.5 heads.

Up until recently the truck ran fine, but would smoke on fire up until it warmed up. (typical valve seals and guides) but as you can see in the pics the plugs never fouled and were white when I pulled the heads...

I replaced the heads with 096 64cc Vortec heads, Summit Stage 1 Vortec intake, Summit K1103 cam kit and a Cloyes true roller TC.

Since then the engine runs like a raped ape but....It smokes like a freight train once it warms up... The more RPMs the more smoke. @ 5k you cant see past the end of the truck....

The first thing I thought was an oil saturated exhaust....Nope smokes just the same with no exhaust.

Then I thought my PCV may be pulling in oil from the new valve covers....plugged it and no change.

So then I took a look at the retainer to seal clearance and it was way too tight for comfort, pulled the springs and retainers and indeed a couple of the exhaust side seals were scarred up. Replaced all the seals with new positive viton seals. Installed a high lift kit to make sure that I have plenty of clearance....still smokes

I thought maybe I was pulling oil from the valley through the intake gasket, but all my plugs are oil fouled equally and the truck idles and runs perfectly.

Is it possible that the added compression has pushed my oil control rings over the edge? I have very little blow by coming out the valve covers with the PCV pulled and none with the PVC hooked up.

Any suggestions are welcome....

Attached Images
     

Last edited by screamin_c10; 12-23-2010 at 04:37 PM.
screamin_c10 is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not 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

Forum Jump


All times are GMT -4. The time now is 08:40 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com