Testing Hei Dist. - 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> Electrical
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 10-09-2006, 01:29 PM
roundman101's Avatar
Registered User
 
Join Date: Nov 2004
Location: belleville, il.
Age: 49
Posts: 21
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Testing Hei Dist.

How do you test a hei distributor to see if it working properly ?? you unhook vacum to set timing, when you hook it back up to carb, it should increase idle slightly !! right or (wrong) ? if not , what does this mean ? vacum advance is bad or could it be something else ??

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 10-09-2006, 05:22 PM
docvette's Avatar
Hotrodders.com Moderator
 
Last wiki edit: Rebuild an alternator Last photo:
Join Date: Mar 2004
Location: Lafayette, california
Age: 62
Posts: 7,362
Wiki Edits: 12

Thanks: 0
Thanked 6 Times in 3 Posts
Doc here,

First..If the car starts , runs and performs reasonably well..there is NOTHING wrong with the HEI...

IF you are experiencing advance problems, configure the car for the following test parameters: (assuming a 350 SBC)
  • Idle, 650 RPM manual 950 Automatic,
  • WARM and Choke WIDE open.
  • pull and plug the vacuum line to the advance unit.
  • connect the timing lamp..
  • locate your timing mark..and set it for ABOUT 12 degrees BTDC
  • Recheck your curb idle, and set it to the above if needed..and if so, recheck the timing mark..
  • Place your vacuum gauge on the advance hose and note the Vacuum , should be AROUND 17 to 21 In Hg AND STEADY..
  • have someone reconnect the vacuum unit..while you monitor the timing..It should Shoot right off the pulley arc..If it does ..It is working fine.
  • Reset the curb idle as above.

Doc
__________________
Aftermarket Solutions
Electronic & Electrical
Innovations
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 10-09-2006, 06:18 PM
roundman101's Avatar
Registered User
 
Join Date: Nov 2004
Location: belleville, il.
Age: 49
Posts: 21
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
When I reconnect the vacuum line to the carb nothing happens. No increase in idle and no movement of timing on tab. The vacuum advance seems to hold suction. Carb. has vacuum, but nothing seems to change.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 10-09-2006, 06:32 PM
Member
 
Last photo:
Join Date: Jun 2004
Location: TN
Posts: 424
Wiki Edits: 0

Thanks: 0
Thanked 2 Times in 2 Posts
Does the port you are hooking the advance vacuum line to have vacuum? If it is ported and the idle speed is low it will not have any vacuum, or very low vacuum, until the throttle is opened.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 10-09-2006, 06:56 PM
roundman101's Avatar
Registered User
 
Join Date: Nov 2004
Location: belleville, il.
Age: 49
Posts: 21
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
carb has vacuum .
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 10-09-2006, 07:50 PM
docvette's Avatar
Hotrodders.com Moderator
 
Last wiki edit: Rebuild an alternator Last photo:
Join Date: Mar 2004
Location: Lafayette, california
Age: 62
Posts: 7,362
Wiki Edits: 12

Thanks: 0
Thanked 6 Times in 3 Posts
Doc here,

Get out your Vacuum gauge/hand Vacuum pump..

Remove the cap, place the pump hose on the advance, and pump it down...The whole advance plate should start to move at about 5 In Hg..and be fully extended about 10 In Hg..If no movement but holds vacuum, check to see the advance plate isn't stuck or binding..Free it anywhere it does..

If it won't move OR hold vacuum..The Diaphragm is blown..replace the vacuum advance unit.

If you don't have a gauge/pump..

Go to ANY manifold source of vacuum..hook the advance there..while idling..It should speed up if it's working..If it does not replace the advance unit.

Doc
__________________
Aftermarket Solutions
Electronic & Electrical
Innovations
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 10-09-2006, 08:48 PM
roundman101's Avatar
Registered User
 
Join Date: Nov 2004
Location: belleville, il.
Age: 49
Posts: 21
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Thanks !!!!

Last edited by roundman101; 10-13-2006 at 11:41 AM.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 06-13-2011, 10:50 PM
Registered User
 
Join Date: Jun 2005
Location: Northern Arizona
Age: 63
Posts: 2
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
HEI Module & Advance - Another Question - timing??

Well I just came back to this forum and even updated my info. I'm having an issue with my 1971 Chevy PU with a Crate engine #12496968. This has the GM 1104067 HEI Dist. I found this "Old" Thread which seems to answer the question - sorta. I just wanted to run my "scenario" by to see if I could get some more in put on it.

The engine has been in the PU for probably 4 years but probably has only 3000 miles on it - if that much.

It ran fine - until it didn't! I've checked timing several times and it always set OK and stayed set and showed by the timing light that it was advancing.

I had the vacuum advance line on constant vacuum port from the beginning until I reread the instructions for the engine and it advised plunging into the ported source - I changed it and checked that it was still advancing. I started to get a pop now and then that I attributed to Carburation - until I put the light on it again and several things happened. First I had set it back to about 8 Deg BTDC. Tightened it down good and checked it stayed @ 8. Ran it awhile - checked and it had advanced to about 12-14 BTDC. Then I set it back to 8 BTDC and checked to see if it was advancing and it was not - it is retarding - every time I increase RPM by about 4-6 degrees.
I checked several times with the vac line on and off - but it is retarding now!!!

Any Ideas?? Is this the Vacuum advance or the module??????????


I started chasing this because I had rejeted my Edlebrock carb for 7000 feet and then moved to 5000 ft but it just would not run right so I went back to stock then richer from there. Seemed to be working except when the weather got hot and then it seemed to run bad and seemed to pop now and again. Then it got hard to start after running around town - like the starter was dragging ( it is a new starter and does not drag when cool)) or it was just hot and too advanced???????

Any thoughts - I appreciate any help and sort of need this truck now as a daily driver.

Thanks - LBM
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 06-14-2011, 04:31 PM
Registered User
 
Join Date: Jun 2005
Location: Northern Arizona
Age: 63
Posts: 2
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Why does HEI retard with blown Vac Advance

So I have figured out the Vac Advance has blown - won't hold vacuum. And I have done a lot of searching on just what the HEI Ign module does - sort of. What I don't get is why the timing is retarding now with no Vac advance.

When I rev the engine instead of the timing light showing advance of any amount it shows it retarding. I can turn the Dist and the mark will advance or retard and when I set it at 6 to 8 deg it is definitely out of the sweet spot so it likes more advance and then it retards when I speed up RPMs??

Would sure appreciate some help here.

LBM
Reply With Quote Quick reply to this message

Recent Electrical 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
HEI mallory dist ?????? weedhopper Electrical 5 08-21-2006 07:53 PM
Mallory 85 Series HEI Dist. Houman SS '70 Engine 4 05-11-2005 12:49 PM
HEI dist. mods. Rob85K10 Electrical 3 01-10-2003 06:06 PM
Do I Need Little HEI Box for New HEI Dist? Mr.56Chevy Electrical 0 12-23-2002 02:38 PM
GM HEI Dist. curve kit?? john69 Engine 4 09-24-2002 07:48 AM


All times are GMT -6. The time now is 04:11 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.