1966 Impala Cranks but will not start - Impala Tech
Electrical & Wiring Troubleshooting electrical problems

 3Likes
  • 1 Post By Big Dave
  • 1 Post By japete92
  • 1 Post By 66ssimpala396
 
LinkBack Thread Tools
post #1 of 14 (permalink) Old 01-08-2020, 10:35 AM Thread Starter
 
 
Join Date: Jan 2020
Posts: 5
 
1966 Impala Cranks but will not start

Hello, new to the site. My previously running 1966 Impala now will not start. It will crank, but will not run. I have checked the points, replaced the coil, new plug wires and battery. I did test the coil with the key on and do have power at the coil. I do see gas squirting into the carburetor. I have recently removed the heater blower from the firewall and heater box from the interior. I have also removed the instrument panel to replace the light bulbs and see if I can get the factory tach to work. May have had a few sparks fly while testing the tachometer, so I think that maybe this has something to do with it? It has not run since I took these things out. All indications seem to point to no spark, but I have reached my level of expertise with this particular issue. Any help with trouble shooting would be greatly appreciated.
66ssimpala396 is offline  
Sponsored Links
Advertisement
 
post #2 of 14 (permalink) Old 01-09-2020, 12:32 PM
Senior Member
 
Join Date: Mar 2008
Location: Moneta, VA
Posts: 875
 
Check to see if you are getting Spark at the Plugs. Either with the old screwdriver trick or with buying a Spark tester (about the size and shape of an ink pen).

-Parting Out over 75 '58 to '73 Full Size Chevy Cars-

Member:

-National Impala Association
-Vintage Chevrolet Club of America
62BillT is online now  
post #3 of 14 (permalink) Old 01-10-2020, 01:48 PM Thread Starter
 
 
Join Date: Jan 2020
Posts: 5
 
62BillT - thanks for getting me back on track. I will check each plug this weekend.
66ssimpala396 is offline  
 
post #4 of 14 (permalink) Old 01-10-2020, 01:58 PM
BA.
Moderator
 
Join Date: Aug 2008
Location: Miamisburg, Oh.
Posts: 3,229
Blog Entries: 15
 
Agree with Bill there. In addition to his 2 methods, I used to take one out and lay it on the header or intake manifold and look for the spark to jump across the plug gap.

When you say you checked the points, do you mean you actually checked with an old Dwell Meter, or you used a feeler gauge on the gap, or what exactly?


Out of curiousity, if you do have spark, did you happen to try spraying any Starting Fluid into the carb to see if you get different symptom or maybe it runs for a little bit?

HOW A NOVICE REBUILDS A 66 IMPALA CONVERTIBLE:
http://www.impalas.net/forums/blog.php?u=1432
BA. is offline  
post #5 of 14 (permalink) Old 01-10-2020, 02:59 PM
Moderator
 
Join Date: Jan 2006
Posts: 12,687
 
A BBC is timing dependent (it is very inefficient and likes lots of timing to run but retarding the spark helps get it cranked; which is one reason I use an ignition box that allows me to retard spark on cranking). If you didn't get the points seated correctly on the weight platform in the distributor your timing will be way off (a good reason to buy a small cap magnetic pick-up or optical gate distributor to go with your ignition box; no points, no wear just set it and forget it).

I am more worried about the sparks.

Quote:
May have had a few sparks fly while testing the tachometer,
Sparks aren't good; nor is letting out the sacred smoke from the wiring. You may have opened a fusible link or blown a few fuses in your fuse box. One of them may be the IGN fuse that powers your distributor (when cranking the power is back fed at full voltage off of the starter motor which is why it sparks on cranking but won't run).

There is a diagnostic logic tree printed in the service manual to help figure out electrical issues.

Big Dave
Big Dave is offline  
post #6 of 14 (permalink) Old 01-12-2020, 09:39 PM Thread Starter
 
 
Join Date: Jan 2020
Posts: 5
 
Ok, good stuff here. I checked each plug, no spark. I checked voltage at coil with key on, and had 12V. Checked coil during crank and had a slight drop which I assume to be the normal “voltage drop”. Held coil to distributor wire to a ground and no spark. I ‘fiddled’ with the points but did not gap them with a feeler gage. Could be problem. Also curious about the ignition wire Mentioned by Big Dave. I have the diagram. Is there a test for this to see if this wire is toast? I have read about test using number from battery to coil directly but this seems like it may cause more problems?
66ssimpala396 is offline  
post #7 of 14 (permalink) Old 01-12-2020, 09:41 PM Thread Starter
 
 
Join Date: Jan 2020
Posts: 5
 
Also, tried started fluid in bowl, no go. Carb is squirting fuel fine.
66ssimpala396 is offline  
post #8 of 14 (permalink) Old 01-13-2020, 09:55 AM
Senior Member
 
Join Date: Mar 2008
Location: Moneta, VA
Posts: 875
 
I would now proceed with a new set of Points along with a new Condenser and set with a Dwell Meter. Range is 29-31. I always go with an exact 30 on the Meter.

-Parting Out over 75 '58 to '73 Full Size Chevy Cars-

Member:

-National Impala Association
-Vintage Chevrolet Club of America
62BillT is online now  
post #9 of 14 (permalink) Old 01-13-2020, 10:10 AM
Moderator
 
Join Date: Jan 2006
Posts: 12,687
 
If you are going to retain points you need to invest in a tach-dwell meter.

https://www.ebay.com/i/223831902838?...xoCDv8QAvD_BwE

Big Dave
BA. likes this.
Big Dave is offline  
post #10 of 14 (permalink) Old 01-13-2020, 04:07 PM
Senior Member
 
Join Date: Dec 2012
Location: virginia
Posts: 370
 
I do not know what 'fiddling' with the points means but the car will not start if the points are not set set properly. That may be only part of your problem(s). If the car is not running, one must set the point 'gap' with a feeler first. Re-set points with dwell meter after it is running.

To set point with feeler one must turn the engine 'over' (a wrench on the nut on the crank may be used) manually until the points are at max 'open'. Remove the distributor cap to see the point gap. Point gap for a small block is 0.019" for new points, 0.017" for 'used' (I do not know the BB gap, never tuned one). A dwell meter will allow fine tuning after the engine is running; 30 degrees is ideal. Also, changing the dwell, changes the timing.

Not saying gapping the points will get you started, but you have no chance if they are not.

Pete
BA. likes this.
japete92 is offline  
post #11 of 14 (permalink) Old 01-13-2020, 05:04 PM
Moderator
 
Join Date: Jan 2006
Posts: 12,687
 
Quote:
Originally Posted by japete92 View Post
I do not know the BB gap, never tuned one.
Pete
BBC and SBC share the same distributor. Only difference is the ignition curve which is the weights and springs used.

The tens of other part numbers reflect different combinations of materials used such as a cast iron body or an aluminum one, or whether it has a Tach drive or not. There are changes internally such as stops (adjustable) and oil tubes with bearings, or no oil tube with brass bushings. But basically all are interchangeable (with the exception of the tall deck truck BBC block which has a taller distributor).

Big Dave
Big Dave is offline  
post #12 of 14 (permalink) Old 01-14-2020, 12:56 AM
 
 
Join Date: Jul 2018
Location: Eastern Pennsylvania
Posts: 4
 
A bad condenser in the distributor also will not allow the engine to fire.

Just an old Chevy lover that has one more 65 or 66 Impala left to build when I retire in a couple of years
Theragtopguy is offline  
post #13 of 14 (permalink) Old 01-15-2020, 12:13 PM Thread Starter
 
 
Join Date: Jan 2020
Posts: 5
 
Fixed! It was the points gap. I purchased a new set of points with a condenser and took the time to gap properly by allowing the points to reach max open, then used feeler gauge to establish the proper gap. After a few turns, she fired up. Thanks for all of the help.
62BillT likes this.
66ssimpala396 is offline  
post #14 of 14 (permalink) Old 01-15-2020, 03:56 PM
BA.
Moderator
 
Join Date: Aug 2008
Location: Miamisburg, Oh.
Posts: 3,229
Blog Entries: 15
 
Quote:
Originally Posted by 66ssimpala396 View Post
Fixed! It was the points gap. I purchased a new set of points with a condenser and took the time to gap properly by allowing the points to reach max open, then used feeler gauge to establish the proper gap. After a few turns, she fired up. Thanks for all of the help.



that's awesome!

HOW A NOVICE REBUILDS A 66 IMPALA CONVERTIBLE:
http://www.impalas.net/forums/blog.php?u=1432
BA. is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Impala Tech forums, you must first register.
Please enter your desired user 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:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



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

 
For the best viewing experience please update your browser to Google Chrome