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Chevylvr7 10-03-2017 07:40 PM

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.!

Coley 10-03-2017 07:52 PM

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

AussieinNC 10-03-2017 08:08 PM

Re: Electrical
 
1 Attachment(s)
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?

:chevy::chevy::chevy:

AussieinNC 10-03-2017 08:10 PM

Re: Electrical
 
Quote:

Originally Posted by Coley (Post 8053326)
...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...

:chevy::chevy::chevy:

franken 10-03-2017 10:10 PM

Re: Electrical
 
You need to get a voltmeter and describe the problem with more than won't fire.

Steeveedee 10-03-2017 11:11 PM

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.

demian5 10-04-2017 04:02 PM

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.

Coley 10-04-2017 04:37 PM

Re: Electrical
 
Quote:

Originally Posted by demian5 (Post 8053886)
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

In The Ten Ring 10-04-2017 05:12 PM

Re: Electrical
 
Anytime working with a battery, SAFETY GLASSES/FACE SHIELD.


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