got the car back the other day from the mechanic after 2 weeks, he's super busy and only got to it the other day, told me the fuel pressure was slightly less than 1 psi. brought it back to my garage, checked the fuel pressure, was over 4 psi with the engine not running, so it seems good to me, still ran bad, swapped out cap, wires, plugs, no change. filter clean, hoses all replaced and look good. I'm running out of options at this point, mechanics here are swamped and dont really have time to fiddle with it, I've done everything I can think of and what's been suggested here and it's too far to drive it to a city even if I knew someone who could fix it. I'm feeling like just buying a running rx in the first place would've been smarter.

 

Wish you were closer. I'd look at it. I also have a 1979.

These are the things I do in this order until I found the issue(s)

1. Compression test.
2. Monitor fuel pressure while running.
3. If fuel pressure is bad, I'd run a 12V source to then pump.
4. If fuel pressure still bad, replace pump.
5. Think about dropping tank and checking for crud.

 

Is Your engine automatic or stick
Autos exhibit very odd behavior when the ATF level is low or your governor is broken .
Low ATF
- Bogging at low rpms , tack bounces and skips . As it gets closer to low car wants to neutral drop but never does.
Very low ATF
- neutral drop when car is under 5 mph or stopped , revving it will cause violent bucking when the clutch pack does engage that will cause you to burn rubber . VERY stressfull on the trans.



Broken governor
Car will work fine BUT if the governor decides to slide in your trans can pretty much money shift your engine . Happened to me once going 70 mph ( 4500 RPM) car shot up to 7.5 K.

If your **** is stick then ignore this .

 

also thinking about swapping the carb vent solenoid with another i have on hand
anything else?
thanks

 

You've replaced most of the ignition. Not sure about the points. If you haven't done so, I'd validate timing. I'm not a good carb guy to give advice.

 

stuff I did today:

1. checked compression, 90 psi w 3 strong pulses on both rotors.

2. checked fuel pressure while running -about 3.8 psi consistently. I had to remove the supply line with a filter I had inserted to rig up the pressure gauge, I found that the filter was restricting flow quite a bit, so I removed it. Took the car for a spin around the block and it ran better, but was still cutting out and backfiring, and the tach would still bounce around like crazy when it would cut out.

back in the garage I disconnected the negative terminal from the trailing coil assuming that the tach wouldn't work at all, but i started it and it did work, still bouncing. thinking I might have the coil positions mixed up I disconnected the negative terminal from the primary coil, tried to start it and just backfired like crazy. suspected the coil might be a problem, swapped with a good one, no changes.

for s**ts and giggles I swapped the primary and secondary coil leads to see what would happen. Drove it and it actually ran (a little) better.
I thought this might indicate a timing problem so I got out the timing lite, plugged the vacuum advance hoses and sure enough the timing was WAY off! I had to adjust the dist all the way over just to get the trailing mark to line up, the leading mark was not within reach as it is.
So, not sure why the timing is so far off. I've never pulled the dist and I doubt anyone else has, and how it could be intermittent if the gear skipped a tooth? do I need to rebuild the distributor?

could the cap be on backward?

confused but making progress

 

First thing I do is not use that mechanic again.

I guess the cap could be on backwards (180 off). Look at my pic and see if the blank plug is in the same place at about the 2 o'clock position. Post a pic the top of your cap.

 

I suppose the cap could go on 180 off, but it wouldn't fit very well. The spring retention clip on the inboard side has a tab built into it that fits into a slot on the cap to prevent that.

 

I'll have to take a look at it tomorrow

 

If the cap looks good, I'd remove the dizzy. Before removing it, align the front cover timing mark on the pulley to the front cover needle. Then remove the dizzy and check the gear mark with the dimple.

 

made a quick trip to my garage to check the distributor cap orientation, it was good so i lined up the timing marks, pulled the cap, the rotor was pointing straight up, so I worked it back and forth to see if the advance mech was sticking, it seemed to have too much travel, pulled it off and could see wear inside the rotor where it was slipping, had another good one handy, installed, started it and it seemed to run very smooth, the tach was still bouncing, so that may be a separate issue? have to work today so will have to go back tomorrow or later tonight to drive it and see how it performs.

 

If you have an after-market tach you could hook it up to see if it also bounces. If you doesn't, the tach itself is probably bad.

 

I don't but might be able to find one. connected across the trailing coil?

 

yes

 

set the timing and drove the car, it idles ok but still having problems with poor performance, backfiring, tach etc. checked carb float levels, front level was high, at the top of the window, back was about right, not perfect but the engine has run good before like this.
I took off the air cleaner cover to look in the carb while it was running, looked ok, no flooding, but I got a nice high voltage shock just touching the air cleaner and leaning on the car. I was no where near any of the plug or coil wires. shut off the lights to look for arcing, coudn't see or hear anything.
I made a couple videos, but cant upload the mp4's

 

For the shocking, you might try adding another ground from the battery. If you have the original battery cables, you might try replacing them.

 

I replaced the ground cable already, even though it was in good shape. it was one of the first things i did when I started having this problem

 

I ran a wire from negative battery terminal to engine block, didn't change the performance problems, didn't get zapped when I touched the air cleaner but didn't try too hard to see if I'd get shocked. I can't help thinking the performance and tach problems are related because they usually occur together and also the shocking thing.
these other things(fuel press, rotor) just made it run even worse, so i guess it could be other small things like this. maybe I should go ahead and replace plugs, wires, cap, points, condensers, battery cable, etc to rule them out, but so far throwing parts at the problem hasn't helped that much. and like I think I said before I think this was the reason the car sat in the first place according to what the PO told me

 

It's never a bad idea to replace wear items on a car that has sat for some time and you don't know when those part where serviced last. Things like cap, rotor, plug wires, points, and even battery cables I consider service items.

 

i replaced all that stuff 3 years ago when I got the car, except for the battery cables which the negative was replaced this year. cleaned and coated tank, new fuel pump and filter. driven 5 thousand miles since I've had it, would probably be a lot more if it weren't for this recurring problem. I would think that stuff would still be good

 

I agree. The shocking and tach behavior could be related. Only a couple of things can cause that. One is that by you touching metal you are completing the ground. The other is that there is a break in one of the high voltage/amp circuits. Could be alternator or ignition wires.

 

OK, so how do I go about testing the circuts, it seems to be charging the (new) battery ok, lots of little wires in the distributor to test? what else?

 

I'd start by replacing the spark plugs wires. They don't have to be new just for testing. I always keep an otherwise good replaced set just in case.

I like the NGK set from RockAuto. https://www.rockauto.com/en/catalog/...plug+wire,7224

NGK (8172) RC-ZE97A Spark Plug Wire Set

As for the alternator, you can always just remove the belt to test. This way it's not putting out any current. You won't be able to drive very far and your battery will drain fast.

 

the NGK's are what I bought 3 yrs ago.
when I remove the alt belt, what am I looking for to happen/checking? for the problem to go away?

 

The tach bouncing and running bad.