The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 10-03-2017, 07:40 PM   #1
Chevylvr7
Registered User
 
Join Date: Apr 2006
Location: Spokane, Wa
Posts: 5
Question Electrical

71 350 longhorn,

new alternator, new battery, new starter, new ignition switch, new HEI dist.

Won't fire, tried everything.....HELP!!!

Had a battery explode, since then it's been a nightmare.!
Chevylvr7 is offline   Reply With Quote
Old 10-03-2017, 07:52 PM   #2
Coley
Registered User
 
Coley's Avatar
 
Join Date: Oct 2011
Location: Victoria, B.C
Posts: 3,794
Re: Electrical

...will it turn over?
Have you checked 7 times to make sure that your (new) HEI distributor is timed correctly to fire for #1 at TDC.
A lot of installs get this wrong or out by 180°.
The best way is to check it on the damper, remove the valve cover to view the valve/spring position and then check it in the cylinder with the plug removed.
If that is ok....is your HEI actually firing off a spark?

All Good
Coley
__________________
....for some men, there is experience, skill and effort....for the others...there is visa and UPS LOL
1966 Chevy 1/2 ton (Florida- Red/white)
1972 Chevy 1/2 ton (California- Blue/white)
2005 Chevy Silverado HD2500/Duramax
2000 Dodge Ram 1500
Coley is offline   Reply With Quote
Old 10-03-2017, 08:08 PM   #3
AussieinNC
Moderator
 
AussieinNC's Avatar
 
Join Date: Jun 2017
Location: Cherryville, NC
Posts: 2,157
Re: Electrical

Battery explosion...WOW!
Did you figure out what caused it?
Ok...back to basics...

1/ Ign on, do you have 12 V on HEI + connection? Supply wire from Ign switch must be 12 G or larger...make sure you havent connected Ign to Tach terminal on HEI connector...
2/ New HEI distributor...does it have the module in it and is it wired correctly?
3/ Missing rotor button?
4/ Distributor timed correctly? Bring cyl #1 to TDC on compression, remove the cap and make sure rotor is pointing to #1 cyl...firing order clockwise, 18436572......see pic...
5/ Does the starter spin the engine over?

Usual suspects...
fuel supply ok?
does the rotor spin when engine cranks over?

Attached Images
 
AussieinNC is offline   Reply With Quote
Old 10-03-2017, 08:10 PM   #4
AussieinNC
Moderator
 
AussieinNC's Avatar
 
Join Date: Jun 2017
Location: Cherryville, NC
Posts: 2,157
Re: Electrical

Quote:
Originally Posted by Coley View Post
...will it turn over?
Have you checked 7 times to make sure that your (new) HEI distributor is timed correctly to fire for #1 at TDC.
A lot of installs get this wrong or out by 180°.
The best way is to check it on the damper, remove the valve cover to view the valve/spring position and then check it in the cylinder with the plug removed.
If that is ok....is your HEI actually firing off a spark?

All Good
Coley
I always check em 8 times...not 7....once for each firing cycle...haha

But I do know what you mean...not first time its bitten me...

AussieinNC is offline   Reply With Quote
Old 10-03-2017, 10:10 PM   #5
franken
Registered User
 
Join Date: Jun 2013
Location: Somewhere
Posts: 3,052
Re: Electrical

You need to get a voltmeter and describe the problem with more than won't fire.
franken is offline   Reply With Quote
Old 10-03-2017, 11:11 PM   #6
Steeveedee
Who Changed This?
 
Steeveedee's Avatar
 
Join Date: Jan 2013
Location: Simi Valley, CA
Posts: 10,102
Re: Electrical

Battery explosions are usually due to loose terminals sparking during cranking. OR you could be like a guy I used to work for that would hook a 12V battery up to jump start a tractor with a 6V system. Fortunately the big chunks missed me, and I got the acid rinsed off before I went blind. Lots of crazy running loose in the world.

Please provide us with some pictures. They may help in the diagnosis.
__________________
~Steven

'70 Chevy 3/4T Longhorn CST 402/400/3.56 Custom Camper

Simi Valley, CA
Steeveedee is offline   Reply With Quote
Old 10-04-2017, 04:02 PM   #7
demian5
Registered User
 
demian5's Avatar
 
Join Date: Aug 2016
Location: Lake Forest, CA
Posts: 2,177
Re: Electrical

Drop a Q and run.

Did the truck have HEI before? If no, you need to run a new wire from the fuse block to the HEI.
__________________
"Work hard, use your vacation days."
1970 C15 GMC Long Bed
1986 C20 Scottsdale
1983 K2500 Sierra Classic Suburban 6.2
Instagram: C10sofOC
demian5 is offline   Reply With Quote
Old 10-04-2017, 04:37 PM   #8
Coley
Registered User
 
Coley's Avatar
 
Join Date: Oct 2011
Location: Victoria, B.C
Posts: 3,794
Re: Electrical

Quote:
Originally Posted by demian5 View Post
Did the truck have HEI before? If no, you need to run a new wire from the fuse block to the HEI.
....good point.

How many volts do you have at the HEI right now with the main power wire?

If you are using the original, tiny little yellow power (+) wire...you might have 8 volts or less arriving at your HEI unit and this isn't going to cut it.

Check this voltage....and post up the number.

All Good
Coley
__________________
....for some men, there is experience, skill and effort....for the others...there is visa and UPS LOL
1966 Chevy 1/2 ton (Florida- Red/white)
1972 Chevy 1/2 ton (California- Blue/white)
2005 Chevy Silverado HD2500/Duramax
2000 Dodge Ram 1500
Coley is offline   Reply With Quote
Old 10-04-2017, 05:12 PM   #9
In The Ten Ring
Registered User
 
Join Date: Jun 2013
Location: West Virginia
Posts: 6,421
Re: Electrical

Anytime working with a battery, SAFETY GLASSES/FACE SHIELD.
In The Ten Ring is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not 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

Forum Jump


All times are GMT -4. The time now is 07:44 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com