'78 Brat electrical issues

[DatSub]

My Brat has been running extremely poorly and I think it's something electrical.

 

I recently had some people work on this car and since it was returned to me, it's been bogging down a lot. When it does this, power cuts, I have to drop gears and give it the beans to get anywhere at all & I can smell tons of uncooked gas. Backfires too, mostly from carb, but also from exhaust.

 

Also, since it was returned, the indicator lights have been all effed & all gauges are bottomed out, except the speedo, which appears to run a bit slow. The only one that works is the parking brake indicator. When I have it on and hit the left turn signal, the fasten seat belts light flashes. The right turn signal just makes the brake light dim and brighten. Turn signals themselves work fine, as well as the headlights.

 

Here's what I've done so far:

 

Checked battery - holds charge @ 12.2 & have swapped with another same story.

Checked alternator - runs @ battery initially after start-up goes up to 15.2, then settles to 13.4-14.2 depending on how it's idling(I have no choke connected at the moment, but the problem is irregular in interval, so that doesn't seem to be a likely culprit). Because of it being up to 15.2, I swapped in a new voltage regulator. Works a LITTLE better, but still bogging down!

Checked impedence of coil @ all terminals - numbers match up.

Swapped fuses

Checked continuity - both battery terminals have continuity to the body - is that normal?

 

Heads are freshly rebuilt.

Fuel pump & filter are relatively new, so it's unlikely that's the problem.

 

I've also heard that alternators can still be going bad, though appearing to give fine voltage - could this be the case?

 

Kinda off-note: Can I swap in an EA-81 internally regulated alternator or do I then have to change out the distributor and coil as well? I've been thinking about doing the whole upgrade, but only have cash for the alt.

 

I realize I may have multiple problems, I am just stumped as all the diagnosis I have done so far has been fruitless, and it just seems strange. Any ideas?

 

DatSub

[Brat78]

What was it in the shop for?

[DatSub]

Well... I bought it from a shop. They re-built the block, but apparently didn't do much else, though it was described to me as a "daily driver" and would be able to take me around for work. I barely got home and it was barely running & misfiring a bunch, and I demanded they take it back and work on it. It turned out it was crossed spark plug cables! Even then, I found tons of weirdly wrong things, like really loose connections, 5 of the 8 fuses were the wrong amperage, etc.

 

UPDATE:

 

Found that the bulbs in the dash are blown, by way of switching them around. Seems like something surged & blew some ************. Also, I wiggled the wires back there and now the gas gauge is all the way to the top. I am not sure, but I am pretty sure I don't have a completely full tank, though it may be nearly full. Haven't tested speedo.

 

Any other things I should check? What about that resistor on the coil?

 

Oh! I also checked the voltage and it is much more stable with this new voltage regulator. I didn't observe it go above 14.2 even when pulling the throttle.

 

Thanks!

DatSub

[talldude]

Whenever a bunch of things go wrong electrically, there is a chance you have a bad ground somewhere. Check all your ground wires/straps to make sure they are connected and that there is no corrosion or oxidization at the connection. Being old cars, even connected wires can have a lot of resistance and won't let enough electricity through.

[DatSub]

That's a good point, talldude. Especially now that I've gone through and replaced the coil, alternator, and voltage regulator & that didn't fix it(though it does seem a *little* better).

 

Also, please tell me if this seems to be a symptom of bad grounding - usually only my brake light indicator works in my dash - nothing else does except the gas alternates between showing empty and showing full. Well last night I fired it up and once it was warmed up, one of the turn signal indicators was flashing. My turn signal wasn't on and it was flashing irregularly.

 

Either way, I'm going to go through a diagram and check all the ground points. Thanks for the tip and I'll let you know how it goes. The next step if that doesn't work is to check the fuel pressure.

 

Thanks again!

Datsub