67 factory tach not working w/photos of pcb - Team Camaro Tech
Electrical & Wiring Troubleshooting electrical.

Reply
 
LinkBack Thread Tools Display Modes
post #1 of 17 (permalink) Old May 27th, 12, 01:26 PM Thread Starter
Senior Tech
BARTELL
 
Join Date: Oct 2007
Location: HAZEL CREST, IL
Posts: 381
67 factory tach not working w/photos of pcb

Hey guys,
MSD 6AL, Blaster 2, and dist. Had OE tach plugged into box and got nothing. After reading posts, switched tach wire to neg coil post. Still nothing. Pulled out gauge cluster and took photo of PCB. Any connections missing? Anything?
BTELL67 is offline  
Sponsored Links
Advertisement
 
post #2 of 17 (permalink) Old May 29th, 12, 04:18 PM Thread Starter
Senior Tech
BARTELL
 
Join Date: Oct 2007
Location: HAZEL CREST, IL
Posts: 381
Re: 67 factory tach not working w/photos of pcb

Hooked up tach adapter today. Getting reading now, but seems low and slow. Oh well, it's a 45 yr old tach right??!! LOL.
BTELL67 is offline  
post #3 of 17 (permalink) Old May 29th, 12, 04:52 PM
Gold Lifetime Member
Steve
 
Farm Boy's Avatar
 
Join Date: Feb 2005
Location: The California Republic
Posts: 1,754
Re: 67 factory tach not working w/photos of pcb

You can adjust the tachometer. There is a potentiometer on the tach for calibrating it. You can access it thorough a hole in the back of the tach housing. The hole on mine was covered with a small piece of paper. I suggest you use a small plastic screwdriver. You can get a plastic screwdriver at Radio Shack. Hook up a known good tach to your engine and dial in your tach to match it.






Steve

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

I drove it for the first time in 1972 when I was 15.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Better looking than a '56 Ford or Plymouth.
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Farm Boy is offline  
 
post #4 of 17 (permalink) Old May 29th, 12, 04:58 PM Thread Starter
Senior Tech
BARTELL
 
Join Date: Oct 2007
Location: HAZEL CREST, IL
Posts: 381
Re: 67 factory tach not working w/photos of pcb

Can I rent that gizmo you got to calibrate from an auotparts store?
BTELL67 is offline  
post #5 of 17 (permalink) Old May 29th, 12, 04:59 PM Thread Starter
Senior Tech
BARTELL
 
Join Date: Oct 2007
Location: HAZEL CREST, IL
Posts: 381
Re: 67 factory tach not working w/photos of pcb

Cool Steve! I was wondering what the hole was for. Mine is not covered by the paper anyore.
BTELL67 is offline  
post #6 of 17 (permalink) Old May 30th, 12, 08:52 AM
Senior Tech
Michael
 
Join Date: Apr 2010
Location: Lutz, FL
Posts: 1,918
Re: 67 factory tach not working w/photos of pcb

Doesn't the 6AL box have a tach feed from the box?
mahunt is offline  
post #7 of 17 (permalink) Old Jun 4th, 12, 11:04 AM Thread Starter
Senior Tech
BARTELL
 
Join Date: Oct 2007
Location: HAZEL CREST, IL
Posts: 381
Re: 67 factory tach not working w/photos of pcb

Yes
BTELL67 is offline  
post #8 of 17 (permalink) Old Jun 4th, 12, 11:05 AM Thread Starter
Senior Tech
BARTELL
 
Join Date: Oct 2007
Location: HAZEL CREST, IL
Posts: 381
Re: 67 factory tach not working w/photos of pcb

False alarm. Tach not working . Vibration is moving the needle. Aarrggghh!
BTELL67 is offline  
post #9 of 17 (permalink) Old Jun 4th, 12, 05:24 PM
Admin/Super Moderator
Brian
 
69-Pace's Avatar
 
Join Date: Jun 2010
Location: Connecticut USA
Posts: 12,511
Garage
Re: 67 factory tach not working w/photos of pcb

You should use the Tach feed on the box with the filter in-line


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

1969 Z11 Pace Car - L48 350cid/300hp - 4 Speed Muncie 12 bolt rear.

Super Moderator Team Camaro
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
to send me a private message
69-Pace is offline  
post #10 of 17 (permalink) Old Jun 4th, 12, 09:27 PM Thread Starter
Senior Tech
BARTELL
 
Join Date: Oct 2007
Location: HAZEL CREST, IL
Posts: 381
Re: 67 factory tach not working w/photos of pcb

I'm using the Tach adapter into the box. Does the Tach filter do something different than the Tach adapter?
BTELL67 is offline  
post #11 of 17 (permalink) Old Sep 25th, 12, 03:43 PM Thread Starter
Senior Tech
BARTELL
 
Join Date: Oct 2007
Location: HAZEL CREST, IL
Posts: 381
Re: 67 factory tach not working w/photos of pcb

UPDATE:
So I'm back to diagnosing the tach prob before I move on to an aftermarket.
I got correct voltage from 6AL box tach out put and tach adapter. MSD told me to check the printed circuit for the line on the pink 12v wire to make sure the 12v is making it from the harness to the tach. However, he said the parking brake uses the same circuit so if it is working then that means the circuit is good and the tach must be bad. The tach is doing nothing. It moves from 500 to 1000 rpm if your rev it enough but it seems to just be moving from vibration. Im gonna fiddle with that calibration screw and see if that does anything.
Any thoughts out there?
BTELL67 is offline  
post #12 of 17 (permalink) Old Sep 25th, 12, 06:26 PM
Admin/Super Moderator
Brian
 
69-Pace's Avatar
 
Join Date: Jun 2010
Location: Connecticut USA
Posts: 12,511
Garage
Re: 67 factory tach not working w/photos of pcb

Quote:
Originally Posted by BTELL67 View Post
UPDATE:
So I'm back to diagnosing the tach prob before I move on to an aftermarket.
I got correct voltage from 6AL box tach out put and tach adapter. MSD told me to check the printed circuit for the line on the pink 12v wire to make sure the 12v is making it from the harness to the tach. However, he said the parking brake uses the same circuit so if it is working then that means the circuit is good and the tach must be bad. The tach is doing nothing. It moves from 500 to 1000 rpm if your rev it enough but it seems to just be moving from vibration. Im gonna fiddle with that calibration screw and see if that does anything.
Any thoughts out there?
Do you have a engine analyzer? I'd double check that you are getting any signal from the box or coil over the feed line.

Then bench test the Tachometer by shunting power and ground then tach signal feed direct to the tach bypassing the PCB and harness wires.
If that works then the issue is in the PCB, if it doesn't work then the Tach needs work or replacing.
If it works then add the PCB and shunt power and tach feed to the right circuit ribbons on the PCB. If it still works then you have a possible power or ground issue with the unit or the connector to the PCB. If it didn't work just shunt power and grounds but run the same new lead to the tach feed from the coil. If that works then the feed line is bad in the harness. PITA process but it is the only way to isolate where the issue is.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

1969 Z11 Pace Car - L48 350cid/300hp - 4 Speed Muncie 12 bolt rear.

Super Moderator Team Camaro
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
to send me a private message
69-Pace is offline  
post #13 of 17 (permalink) Old Sep 25th, 12, 06:38 PM Thread Starter
Senior Tech
BARTELL
 
Join Date: Oct 2007
Location: HAZEL CREST, IL
Posts: 381
Re: 67 factory tach not working w/photos of pcb

Uh.hhhh. what?
Shunting?
BTELL67 is offline  
post #14 of 17 (permalink) Old Sep 25th, 12, 06:46 PM
Admin/Super Moderator
Brian
 
69-Pace's Avatar
 
Join Date: Jun 2010
Location: Connecticut USA
Posts: 12,511
Garage
Re: 67 factory tach not working w/photos of pcb

Quote:
Originally Posted by BTELL67 View Post
Uh.hhhh. what?
Shunting?
To shunt is to bypass existing routes through existing harness or other connections.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

1969 Z11 Pace Car - L48 350cid/300hp - 4 Speed Muncie 12 bolt rear.

Super Moderator Team Camaro
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
to send me a private message
69-Pace is offline  
post #15 of 17 (permalink) Old Sep 25th, 12, 07:12 PM
Banned
Chet
 
Join Date: May 2006
Location: Detroit
Posts: 749
Re: 67 factory tach not working w/photos of pcb

Take tach to gage shop. Have them check it out. Probably dead. OE tachs and OER tachs don't get along well with MSD electronics. There is a thread on here about tach filters. Check it out. I sent my dead OER tach to redline gage and had modern electronics put in it for the cost of a new tach. Can't tell the difference.
154567 is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Team Camaro 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.
NOTE we receive a lot of registrations with bad email addresses. IF you do not receive your confirmation email you will not be able to post. contact support and we will try and help.
Be sure you enter a valid email address and check your spam folder as well.



Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



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