Lotsa smoke at startup. (Stock Chevy 350 with Q-Jet carb) - 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 07-16-2004, 06:51 PM
Member
 
Join Date: Jul 2004
Location: San Jose, CA
Age: 45
Posts: 138
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Lotsa smoke at startup. (Stock Chevy 350 with Q-Jet carb)

Ok, it's me again. Just passed smog, and now I'm willing to invest a little more time and money on this thing. Not quite sure how much though.

Every time I start this thing, it puts out alot of smoke.

When it's cold I can floor it once before starting it, then start it very easily just by turning the key. This is to be expected because it being cold and not running when I floor it activates the fast idle cam.

When it's hot, and I go to start it, I have to turn the key and quickly give it a little gas to get it to start.

Is this normal behavior for a 1977 Chevy PU with a 350 and a Rochester Q-Jet?

I was told by the guy I bought the thing from that it has bad valve seals, and that's why it's blowing smoke whenever I start it up.

Is this correct? Is the only way to fix it to have the heads rebuilt? If I were to have the heads rebuilt is there anything I can also have done without increasing the cost at all or by increasing the cost a little that might improve HP performance or gas milage performance significantly?

What other things might cause alot of smoke on startup?

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 07-16-2004, 07:00 PM
Grumpy
 
Last photo:
Join Date: Dec 2002
Location: D.C.
Posts: 1,447
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
valve seals, oil slipping past rings on startup, nothing show stopping. There are tools so you can replace the seals while the heads are still on the engine. Seals are also real cheap to buy.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 07-16-2004, 07:11 PM
M&M CUSTOM's Avatar
Hotrodders.com Moderator
 
Last wiki edit: Transmission identification
Last journal entry: 1988 Suburban, the project continues.
Last photo:
Join Date: Mar 2003
Location: Northwest Pennsylvania.
Age: 43
Posts: 2,231
Wiki Edits: 9

Thanks: 0
Thanked 1 Time in 1 Post
Valve seals and rings, the 23 year old 267 in my Malibu has the exact same thing, blue smoke at start-up.

For comparison purposes.

If you have black smoke it is from too much fuel.

White steamy exhaust at start-up is normal, BUT after the engine is warmed to operating temperature you would be experiencing a coolant leak into a cylinder from most likely a head gasket failure.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 07-16-2004, 08:08 PM
Member
 
Join Date: Jul 2004
Location: San Jose, CA
Age: 45
Posts: 138
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I will have to look into getting those tools. Are they expensive? Hard to use? Will they work on any vehicle, just V8's or just some V8's?

I'll try searching google and see what pops up.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 07-17-2004, 02:54 AM
Member
 
Join Date: Jul 2004
Location: San Jose, CA
Age: 45
Posts: 138
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I found this:

http://store.autotoolexpress.com/unovvalsprin.html

I just happen to already have exactly this tool, but didn't know what it was for.
(My uncle moved out of the country and gave me all his tools instead of selling them)

Air Hold Fittings.
http://www.toolsource.com/ost/produc...CVGTU782NGBRJ4

What else do I need?

Last edited by Terje; 07-17-2004 at 03:12 AM.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 07-17-2004, 05:46 AM
roys63's Avatar
Member
 
Last photo:
Join Date: Dec 2001
Location: Nc
Age: 63
Posts: 907
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
If this has a auto trans it may be the Modulator valve in the trans pulling trans fluid into the intake, check the hose and see if it is wet in side, This will smoke real BLUE and have a kind of sweet smell ?
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 07-17-2004, 06:16 AM
troy-curt's Avatar
Shop Owner And Troll Hunter
 

Last journal entry: Detailing Eng. Compartment
Last photo:
Join Date: Apr 2003
Location: Prairie Grove Ar.
Age: 76
Posts: 2,646
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
If it was a modulator, it would smoke all the time.

Sounds like valve guide seals to me. And you have the right tools.

Troy

__________________
If you don't make mistakes. your not doing anything.

69 ss rs full custom camaro 98 ISCA grandchampion
69 ss rs bb camaro wifes driver
66 Elcamino 350/all dz parts,ac,windows,loaded,my driver
69 ss chevelle bb conv.fresh frame off
26 T sedan street rod
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 07-17-2004, 03:09 PM
Member
 
Join Date: Jul 2004
Location: San Jose, CA
Age: 45
Posts: 138
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Yes, it is an automatic.

So far:
1. Modulator valve in the trans pulling trans fluid into the intake.
- Smokes real blue all the time.

2. Oil slipping past rings on startup.
- Wouldn't this happen all the time? Not just at startup?

3. Valve seals leaking oil.
- Bluish smoke at startup.

4. Too much fuel.
- I guess this could occur all the time or just at startup. Is there an explanation for why this would only occur at startup? I can't tell if the smoke is blue, black or brown. There's not enough. It doesn't appear to smell sweet. But it does smell a bit like gas.

I'll have to keep looking at it a bit every time I startup and try deciding what it smells like.

I'm guessing that it probably is the valve seals, and it appears to be cheap enough and easy enough to fix. So even if that's not the problem, as long as I don't mess up the valve seals putting in new ones, it won't matter too much if the valve seals were not the problem.

Last edited by Terje; 07-17-2004 at 07:13 PM.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 07-17-2004, 06:57 PM
roys63's Avatar
Member
 
Last photo:
Join Date: Dec 2001
Location: Nc
Age: 63
Posts: 907
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I guess we need a Cristal Ball.
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:
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



All times are GMT -6. The time now is 11:05 AM.


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.