Its a small block chevy, with points and a new carb. Wtf.

Working on Dad's 60 Corvette. We put a brand new Holley brawler 750 mechanical secondary with electric choke on it. In addition we put a used dual-plane Edelbrock intake manifold on it. We got rid of the garbage aftermarket 70s electronic ignition and converted to a single points distributor. It will start up from cold perfectly fine. Around the time the thermostat opens, it cuts off like it turned off the ignition. At that time attempting to restart it becomes incredibly difficult and it starts kicking back against the starter regardless of how much initial timing is dialed in. We suspect that a bad starter so we swapped over to a gear reduction starter and all new battery cables. I have it straight wired at this point through the ballast resistor to the coil to eliminate the variable of all the GM wiring. The only things the same in the system as far as fuel system and ignition go since we started is the electric fuel pump, the ballast resistor, and the coil. I am absolutely berkeleying stumped. It pulls 18 in of manifold vacuum and idles Rocksteady and then just cuts the hell off for no apparent reason. Any ideas? Stuff to try? I don't want to shotgun more parts at it if I can help it.

Vacuum lines, or was '60 pre-vacuum crap?

OK, long shot here and going from a distant memory,  might have been a Ford is memory serves, but I seem to recall an interaction between the electric choke circuit and the coil 12 volt. Is it possible that you are loosing coil voltage when the choke opens?

Pete

New condensers are E36 M3. DOA's are commonplace. Is it running a new coil too?

Condensor failure is likely, especially if it is new. Find an old stock one if you can, all the newly made ones seem bad, regardless of brand or ignition system maker.

Points switch ground on ignition coil.  I’m thinking along same lines as NOHOME re you’ve got the little black wire to the coil mixed up with, or connected to, the electric choke such that it’s giving the coil an unswitched ground as the choke opens.

Are you setting the points using a dwell meter or feeler gage?

If you are using a feeler gage try opening the gap and resetting the timing. Even with the ballast resistor, too much dwell at idle will cause the ignition to get hot and cause problems  

Also make sure the contacts on the points are hitting evenly so you aren’t just burning off the corner and heating them up. 

The electric choke is grounded through the carburetor body. The only connection at the negative side of the coil is to the distributor points. On the positive side of the coil I have 12 volts in from the ballast resistor output side. The input side of the ballast resistor go straight to 12 volts and the car is triggered off that feed as well as the relay for the electric fuel pump. They all tie in with one another at the switched side of the ballast resistor. In addition the choke is open completely for a couple of minutes before the behavior exhibited self.

Factory specifications for dwell we're between 25 and 30 degrees. It ran best with dwell at 35 degrees according to my antique dwell meter. The points and condenser were old ones that were supposedly known good. We have new ones on the Shelf to try shotgunning at it that we picked up at Napa. Ignition coil is an aftermarket Stinger brand that was on the car when we bought it in the mid-90s

When it's warmed up and the choke shuts off, what happens if you hold the choke partially closed, like with your finger?  Will it run then?

That dang old garbage electronic ignition, man. I hate those things. Now how do we make your points system not break every time you start the car... 

With a carbureted car, cutting off like a light switch is spark. Have you put a timing light on it when it won't start?

In reply to Dr. Hess :

Will not. However, if you hold the carb wide open, it stops kicking back against the starter.

Vigo said:

That dang old garbage electronic ignition, man. I hate those things. Now how do we make your points system not break every time you start the car... 

With a carbureted car, cutting off like a light switch is spark. Have you put a timing light on it when it won't start?

Honestly  i didn't think about that! Im fairly certain that its spark as well. Just dont know WHY.

Dad really wanted a return to points when the aftermarket parts crapped out. I havent messed with points and a ballast resistor since about 6 monts after i started driving. And even then, i sucked at it. 

I understand it’s a ‘60 Vette and there is a need for some modicum of originality.  But let me tell you, nothing works better than the big fat head HEI that came out in ‘75 and that they made eleventy badillion of.  They work with one wire to +12v.  Coil is built in.  You can snag one at a junkyard (but it’s getting harder) for the price of a good chicken dinner.

 Ive been talking about it with him. Hes determined to stay points for now. And its my dad, so, sometimes you just say yessir.....

Kicking back against the starter usually means the timing is too far advanced.

Since it's points, I recommend you baseline the engine by doing it this way:

Assuming you've gapped the points properly...

Turn the engine over to top dead centre on #1 cylinder, according to the timing marks. Now turn it forward until it's advanced the 8 degrees or whatever it's supposed to be.

Take the distributor cap off and ensure that the rotor is pointing at #1 wire terminal. If it's not, rotate the distributor body so it's pretty much centered on it.

Disconnect the wire that goes from the distributor to the negative side of the coil.

Put the probe of your test light into the positive battery terminal and connect the clip to the wire coming from the distributor that was formerly connected to the negative terminal of the coil. The light -should- light up if the points are closed, you might have to rotate the distributor body a little bit one way or the other.

Now, slowly rotate the distributor body in the opposite way to the rotation of the rotor until the test light goes out. Your distributor is now timed very close to correct. Lock it down and hook everything back up again.

Now,  manually open the choke plate on the carburetor and hold it there, cycle the throttle open and shut with your hand, once it's shut, let go of the choke plate. The choke plate should stay slightly open now. This should set the idle stop screw on the slow idle position.

Back the idle speed screw on the carburetor out until it no longer contacts the stop. Turn it back in until it just touches, now turn it in one and a half turns.

Gently turn each mixture screw in until it seats and then back it out one and one half turns.

Pump the gas to set the choke on fast idle and start the engine.

It should start and run at fast idle, let it warm up and get it on to the slow idle stop. Turn each mixture screw in or out the same amount until the engine won't run any faster using only the mixture screws.

Adjust the idle speed screw to your correct idle speed, you might have to do this in Drive if it's an automatic. Have someone hold the car on the brake.

Now get your timing light out, disconnect and plug the vacuum advance hose and set your base timing.

The engine is probably dying at idle because the timing is too far advanced and the throttle plates have been shut too far in order to get the high idle speed down which is caused by excessive spark advance.

Remember, the only way to diagnose something is to take it back to stock settings and start from scratch, ensuring that all the basics are correct. 

It's simple. Fuel, Air, Spark and each one has to happen at the correct time and quantity.

You honestly have the simplest engine configuration on your hands. One fuel line and three wires will make a carbureted, points ignition engine run.

Stick a Perktronics in the old points dizzy.  He'll never know the difference.  They make 'em for those, 'cuz sometimes that big old stupid HEI dizzy don't fit jammed up against the firewall.  Because GM decided to put a big, maintenance-intensive component right smack dab at the furthest back point on the engine they built the most of.  (In fairness, Chrysler did, too, but only on the small blocks).

If you want the benefits of electronic ignition, you can use the points to trigger a Ford TFI module which can fire a conventional looking coil.

You'll get a nice, hot, fat spark and the points will last nearly forever since they're switching a transistor on and off instead of handling ignition voltage.

If the module fails for some reason, change a couple wires and you're back to points ignition which will get you home. 

TurnerX19 said:

Condensor failure is likely, especially if it is new. Find an old stock one if you can, all the newly made ones seem bad, regardless of brand or ignition system maker.

I’m with Crackers and Turner here. Condenser failure. 

COIL   Do you have another coil to try?

    Better; get a (new) RED MSD coil and be sure to mount it vertically (or get the black vibration one and  mount it any position).

       Even better use the points to trigger a MSD box, less load on the points and more spark.

   The MSD coil might not need the ballast, not sure on that.

      Concur with others the ballast could also be not helping.

       Nice thing about points, it can be fixed anywhere anytime, even if you add the MSD box, if you think the MSD failed, you can easily wire it without the MSD to get home.  If you don't drive a lot of miles or run high RPM then points are fine.

volvoclearinghouse said:

Stick a Perktronics in the old points dizzy.  He'll never know the difference.  They make 'em for those, 'cuz sometimes that big old stupid HEI dizzy don't fit jammed up against the firewall.  Because GM decided to put a big, maintenance-intensive component right smack dab at the furthest back point on the engine they built the most of.  (In fairness, Chrysler did, too, but only on the small blocks).

Did this in my Uncles 74 corvette with at 350, worked like a charm.  He wreck that one, his new 74 has a 454 in it.

Dad swapped in fresh points and condenser today. Kept running after thermostat opened, and restarted. Will repeat the test a few more times, and then we will say that its fixed. But, its definitely a move in the right direction!

Fingers crossed for you and your Dad!

Cool. How did he get the broken oil fitting out?

volvoclearinghouse said:

Stick a Perktronics in the old points dizzy.  He'll never know the difference.  They make 'em for those, 'cuz sometimes that big old stupid HEI dizzy don't fit jammed up against the firewall.  Because GM decided to put a big, maintenance-intensive component right smack dab at the furthest back point on the engine they built the most of.  (In fairness, Chrysler did, too, but only on the small blocks).

+11 Billion. 

Sounds to me like it is not running completely on just the idle circuit and you need to set everything from scratch. Throw a vacuum gague on the manifold and set the timing with that and then go through the motions. Also make sure when you are feeding the carb that it is regulated to 5.5psi. I have seen some of the newer rebuilt mechincal pumps kicking out 11-14psi lately and you will nver get it to run.