mstg007

I have points in my distributor, Anyways, a week ago, before I adjusted the points, the engine was running smooth and great! However, Then we reset the points. We have not had any time to readjust them properly. So now, when I start the engine, It starts up fine, however when you place it in gear / drive. It goes to a real slow idle and then dies.

I would like to know what is going on. Anyways, the basic understanding of how the points react with the rest of the engine an so forth.

Thanks for the help

tx65coupe

I would just replace the points with a Pertronix Ignitor and never have to worry about points again. Back when my 65 was still an I6 and was my daily driver in high school, I had to change the points more often or at least as often as the oil. I'm glad I don't have to do that anymore.

I'm sorry I don't have a real answer to your question. Maybe someone else will chime in with some info for you.

JMD

To adjust points "***** on" you need a dwell meter.

The gap can be set manually by turning the engine to where the points are fully open and useing a feeler guage to set the gap to spec.

Instead of a feerle gauge, the cover to a book of matches works in a pinch...

fakesnakes

It seems you have set the gap too large which creates a very weak spark. When the points are closed, current flows through the coil primary inducing a current in the secondary which builds a magnetic field. When the points open, the secondary field collapses creating a high voltage surge that creates a spark across which ever spark plug the distributor rotor happens to be pointing to at the time. If the points gap is too large, the points don't stay closed long enough to build a sufficient field. The engine may start, but as rpm increases the weak spark can not keep the engine running and it stalls. The time the points stay closed is called dwell and is very important in creating a strong spark.

Take the advice above and replace the antiquated points with an electronic module.

67mustang302

+1 to everything fakesnakes said.

Dump the points, seriously.

mstg007

Thank you! that makes alot of sense.

mstg007

I had a chance to adjust the Points for my engine. However, it is still somewhat hisitating to die alittle once you put the transmission in drive. We had to adjust the idle higher so it would not drop to low and die.
Does this seem normal. Idle is at 1,000 RPM, and the Drive is arond 500 RPM.
This is a 72 302 4BBL.

Any ideas!

kalli

mark already gave a great summary of how it works, I just want to add:
when you change the gap in the points you affect timing.
the hump under the rotor is opening them and when you increase the gap it has the side effect of opening sooner and closing later. this sooner opening will cause the ignition to fire earlier.
So with adjusting your points you probably advanced or retarted your ignition.
Therefor whenever you set them you need to do the timing directly after this (with a timing gun).
If you take all the advise and ditch the points for module, you'll only need to do it once ;-)

Gun Jam

Im just adding my opinion and saying...how bout MSD instead of pertronics

-Gun

Norm Peterson

I remember short-cutting points replacement/resetting to where I only worked with the dwell angle. Set the same dwell every time and the timing stays put, so you never need to loosen the distributor hold-down bolt after the first time.

I also remember using a short gap/long dwell approach in order to get better high rpm capability - the 2.0L Pinto engine was good past 7500 rpm once I got done "tinkering" with it. I did get points bounce as the rubbing block wore, and when the tach started reading a little "high" for a given road speed I knew it was maintenance time again.

When I swapped a different motor into that car, I brought its Duraspark electronics along. I've never looked back. Every once in a while I run across the old dwell tachometer.


Norm