flickering dash/headlights

[ian choplin]

I've learned tonight that i have more electrical issues. I did as Steve suggested and ran a ground from the battery to the case of my 10si alternator. I haven't driven it yet, so I don't know if I've affected the flickering light issue.
My other issues are the oh so common turn signal/brake/marker/dash lights flashing syndrome. When I push the brake pedal the dash, marker and brake lights come on. When I turn on the right turn signal, everything functions properly.
When I turn on the left turn signal, the Scout becomes a strobe light. All lights(except headlights) flash--dash, marker, front and rear lights.
My truck has an older lower front grill and uses the metal bodied front lamps. I added a ground to each lamp to the core support. No change. I "cleaned" at the ground at the left rear tail light. No change. I'm guessing that since my right side works, that my issue is on the left. Am I way off track?
I don't remember if I have a battery to body ground. I do have an engine to body ground.
Should I add a ground at that left rear to the frame? Should there be a battery to body ground? Any other place I should add a ground?
All my bulbs are new w/in the last year.
Sorry for the long post. I've been reading through old threads for quite a while now and have seen some threads like mine. Seems like a lot of them don't follow through with outcomes even after receiving good advice.
Thanks,
Ian

[Eric VanBuren]

Where are you measuring the voltage when you saw it drop to 12v when the lights flickered?

This is when it was not a good thing to have bypassed the ammeter as it's response during and after a volt drop/head light flicker would tell you a lot.

The BHC is suspect but w/o the ammeter it is going to be really hard to diagnose if that actually is the problem and if it is where it is at. You can always punt and run a wire from the alternator's B+ stud to the battery + terminal and see if that stops the voltage from dropping and the headlights from flickering.

Adding all those extra grounds is not necessary and will not help matters. You should have your battery cable going to the block and a minimum 10ga wire to the radiator core support from the battery ground cable. One from the engine to firewall is optional by not required if the other body ground is adequate. Just make sure that all the grounds are good clean bare metal.

The fact that when you use the one turn signal and the rest of the lights start flashing with them indicates you've got a short to ground on that side or a light that is drawing way too much current.

[ian choplin]

Thanks Eric, I'll add a 10ga wire to the alt this evening.
I'm using a voltmeter to measure voltage while driving. It drops to about 13'ish when the lights flicker.
Thanks for everyone's help so far.
Ian

[ian choplin]

More issues this morning. I changed the driver rear brake/tail bulb and redid the ground there. My flashing light issues are solved.
Now, my cheap O'Really's alternator isn't charging. While driving down the highway, I was only showing battery voltage. If I stopped and turned my lights off, voltage would slowly go back to just under 14.
Wonder if a dying alternator has been an issue all along? It only has about 500 miles on it. Would a loose belt contribute to this too?
Ian

[Ronmc1954]

I have had alternators do that before, Ian. Cause flickering that is, the only thing that leads me a different direction would be you said the flicker more when you hit a bump.
Grounds are always a good thing to improve on, such as:
Dash to fire wall, fire wall to fender, fender to nose cap and of course fender to motor.
I am not sure what fuse panel is in an 1980 but in my 75 and 74 I have had to tweek the fuse holders, they get spread out over the years and cause a connection that loose enough to flicker.
Yes, alt belts can slip and cause poor charging but not a flicker.

Ron

[ian choplin]

Was able to replace my alternator today. Now I'm backing to having a charging system. I also ran a 10ga wire from battery + to post on back of alternator. I'll know more in the morning on the way to work.
Thanks
Ian

[ian choplin]

As of this morning, I believe my flickering light issues are fixed. Drove 20 miles to work, no flickering and no blown fuses.
Here's all that I did:
Better grounds at front and rear marker/turn lamps
New alternator
10ga wire from battery pos to alt post
Ground alt case
New rear light bulbs
Tightened bhc
Thanks for everyone's time and advice
Ian

[ian choplin]

Well, I jinxed myself. I was driving this evening and had to use my headlights. After a moment or two, POP went the panel and the stop fuses. I have a small fortune in fuses as of late.
When I went to install another fuse in the "panel", there was some arcing. The fuse didn't pop when I installed it.
I know to most this is a tell tale sign, but I need educated. Obviously it shouldn't do that. Now that I'm back home, I have access to my tools and manuals.
Are there any tricks to narrowing this down?
Another question, I have 5 add-on gauges(boost,pyro,volts,oil,water) that are lit by the panel circuit, is this too much? I am ashamed to admit that I did install a 20 amp fuse where it calls for a 15 and it still popped.
Where do I go from here?
Thanks,
Ian

[Ronmc1954]

Originally Posted by ian choplin

Well, I jinxed myself. I was driving this evening and had to use my headlights. After a moment or two, POP went the panel and the stop fuses. I have a small fortune in fuses as of late.
When I went to install another fuse in the "panel", there was some arcing. The fuse didn't pop when I installed it.
I know to most this is a tell tale sign, but I need educated. Obviously it shouldn't do that. Now that I'm back home, I have access to my tools and manuals.
Are there any tricks to narrowing this down?
Another question, I have 5 add-on gauges(boost,pyro,volts,oil,water) that are lit by the panel circuit, is this too much? I am ashamed to admit that I did install a 20 amp fuse where it calls for a 15 and it still popped.
Where do I go from here?
Thanks,
Ian

Well your causing me to scratch my head now. You mention "pop went the panel and the STOP fuses. Assuming you are talking about the brake light fuse.
I would still take a close look at the fuse holders if an 80 is like my 74 they are glass tube fuses. Look at the fuse holders themselves, they can spread out over time and actually touch each other or not hold the fuse tight causing a flicker when bumped.
If that checks out go in the engine compartment and find the wire loom that goes to the rear of the truck. Disconnect the rear of the truck hopefully the is a connector (I can't remember) them see if the flicker still exists. Just trying to isolate the problem as in the front or rear of the truck.
Good luck.

Ron

[ian choplin]

Thanks Ron. The 1980's use glass fuses like earlier Scouts. I think I may have narrowed it down to the driver side tail light. I will do as you suggested and try to isolate it further to be sure.
Hopefully, I can get back to it this evening.
Ian