Holley Carb Backfire - 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 12-26-2006, 08:13 PM
DeathRattle's Avatar
Some Punk Kid
 
Last photo:
Join Date: Oct 2006
Location: Michigan
Age: 28
Posts: 787
Wiki Edits: 0

Thanks: 0
Thanked 2 Times in 2 Posts
Holley Carb Backfire

Engine is SBC with a holley 670 street avenger sitting on top. Finally got the starter working well so I tried to start it. I only get pops and plumes of smoke out of carb. Should i be only looking at timing or anything else. Maybe something stupid like not enough plug gap? I thought I set it up well but I could be off a tooth.
Crank motor to 10* piston 1 @ TDC.
Aligned oil pump drive with intake pushrod of #5
Mark distrib. body with number one point.
Pointed rotor at with oil pump drive and dropped it in.
It aligned with number one mark and vacuum can was angled 45* across motor.

Tell me if and where i went wrong

Thanks for any replies.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 12-26-2006, 08:27 PM
71C10's Avatar
U.S. Army Retired
 
Last photo:
Join Date: Sep 2005
Location: Texas
Posts: 266
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by DeathRattle
Engine is SBC with a holley 670 street avenger sitting on top. Finally got the starter working well so I tried to start it. I only get pops and plumes of smoke out of carb. Should i be only looking at timing or anything else. Maybe something stupid like not enough plug gap? I thought I set it up well but I could be off a tooth.
Crank motor to 10* piston 1 @ TDC.
Aligned oil pump drive with intake pushrod of #5
Mark distrib. body with number one point.
Pointed rotor at with oil pump drive and dropped it in.
It aligned with number one mark and vacuum can was angled 45* across motor.

Tell me if and where i went wrong

Thanks for any replies.
Make sure you are the compression stroke... the rotor has to be pointed a little counter clockwise of (#1) on the cap when you drop the dist in, (before it meshes with the cam gear) because it rotates clockwise when it meshes with the cam gear.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 12-26-2006, 09:01 PM
Member
 
Join Date: Dec 2004
Location: Madison, WI
Posts: 1,885
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Yes, you are not timed correctly.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 12-26-2006, 09:31 PM
DeathRattle's Avatar
Some Punk Kid
 
Last photo:
Join Date: Oct 2006
Location: Michigan
Age: 28
Posts: 787
Wiki Edits: 0

Thanks: 0
Thanked 2 Times in 2 Posts
Im sure their are different techniques than the one I used so I am open to suggestions for setting initial distributor timing. I followed the on in the book which was oil drive shaft aimed at intake pushrod for number five cylinder when piston one was at top dead.
Thanks for any replies.

EDIT: When it backfires through carb is it more realistic that its off a tooth? or do I just to turn the distributor? I would think if its doing that its way off more than turning can fix.

Last edited by DeathRattle; 12-26-2006 at 09:36 PM.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 12-26-2006, 10:31 PM
71C10's Avatar
U.S. Army Retired
 
Last photo:
Join Date: Sep 2005
Location: Texas
Posts: 266
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
The cam turns one revolution for every two crankshaft revolutions... are you sure that you were on the COMPRESSION stroke of #1 when you dropped the distributor??? If you are doing this by yourself, pull the drivers side valve cover and crank the engine until the INTAKE valve of #1 opens and begins to close, then crank the engine by hand until you get to the approx initial timing you want and drop the distributor in place. Turn the oil pump shaft if you must... and make sure the rotor is pointed at #1 on the cap once the dist is down flush against the manifold.

Good luck and hang in there!

Last edited by 71C10; 12-27-2006 at 04:07 PM.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 12-26-2006, 10:46 PM
larryblack's Avatar
Certified Lead Foot
 
Last photo:
Join Date: Jan 2003
Location: Houston, TX again
Age: 63
Posts: 519
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by 71C10
The cam turns one revolution for every two crankshaft revolutions... are you sure that you were on the COMPRESSION stroke of #1 when you dropped the distributor??? If you are doing this by yourself, pull the drivers side valve cover and crank the engine until the INTAKE valve of #1 opens and begins to close, then crank the engine by hand until you get to the approx initial timing you want and drop the distributor in place. Turn the oil pump shaft if you must... make sure there rotor is pointed at #1 on the cap... once the dist is down flush against the manifold.

Good luck and hang in there!
After you do the previous excellent instructions, connect your timing light to number 1 plug wire. Turn the key on, and adjust the dizzy CCW until the light flashes. You now have the initial timing set. I like to alaign the balancer marker with the 10 on the tab. It is a good starting point. Tighten the dizzy down and fire the engine.

You will still get some poping thru the carb if this is a new cam/engine set up. after a couple of minutes things will settle down and you can watch for leaks and beak in the cam if need be.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 12-27-2006, 10:55 AM
DeathRattle's Avatar
Some Punk Kid
 
Last photo:
Join Date: Oct 2006
Location: Michigan
Age: 28
Posts: 787
Wiki Edits: 0

Thanks: 0
Thanked 2 Times in 2 Posts
Thanks for he advice I am about to go out and do all of this again and see how she goes.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 12-27-2006, 02:04 PM
DeathRattle's Avatar
Some Punk Kid
 
Last photo:
Join Date: Oct 2006
Location: Michigan
Age: 28
Posts: 787
Wiki Edits: 0

Thanks: 0
Thanked 2 Times in 2 Posts
It was 180 out. Break in went smooth. Max temp at 2000-2500RPM was 200 I will change oil and fire it back up and hopefully cam has all its lobes. With rotella and EOS it better. I hope
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 12-27-2006, 04:11 PM
71C10's Avatar
U.S. Army Retired
 
Last photo:
Join Date: Sep 2005
Location: Texas
Posts: 266
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Good deal, enjoy
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 12-27-2006, 05:44 PM
DeathRattle's Avatar
Some Punk Kid
 
Last photo:
Join Date: Oct 2006
Location: Michigan
Age: 28
Posts: 787
Wiki Edits: 0

Thanks: 0
Thanked 2 Times in 2 Posts
Now I have to just get it to idle. If i let off the pedal it stalls. I guess ill just have to fiddle with the idle speed screw and see is i can get it to idle
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
Holley (ProForm) Carb Problem leejoy Engine 30 04-01-2011 11:36 AM
Holley Carb Gas Leak 64Joker Engine 21 07-18-2010 02:28 PM
Holley 4777 carb. questions. TVR383 Engine 16 07-05-2009 02:23 PM
Demon or Holley Carb for 306 Ford? Dino Boreanaz Engine 10 12-09-2006 06:04 PM
Holley carb experts? Others? Why is my truck's fuel bowl being sucked dry? MuscleTruck Engine 5 05-23-2003 12:36 AM


All times are GMT -6. The time now is 05:38 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.