My 1965 Skylark with a 300/355 has stopped running. I was coming on the freeway about five miles from home and of course floored it. When I was almost ready to merge with freeway traffic (we have very little traffic) it started to cutout. At first I thought the carb was running out of fuel, but decided that wasn't the problem as pumping the gas didn't do anything. Seemed fine cruising at 65 mph for a mile or two then I could feel it cutting out more. It got worse as I kept going. I turned off the freeway and headed towards our home. A mile later and about a block from our street it died. I put it in neutral and restarted but it was barely running. I nursed it up the hill and turned to go into my shop. The motor completely died so I go out and opened the gate and had to pushed it towards the shop. I then opened the shop door and had to push it in. I remember what my auto shop teacher said (1964), engine problems are 90% electrical, not fuel pumps or carbs. So I removed the air cleaner top and pumped the throttle a few time and it squirted gasoline. I tried to start it, but it didn't even try to start. Then I removed the distributor cap and rotor, but I can't see the points to see it something happened to the contacts. I guess these are new fangled points as my 1965 Special with a V-6 has points you can see. So I guess tomorrow I will get out my pointy thing with a light in the handle and trace electrical power back to the battery from the distributor. Ugh. Anyone have any ideas what might be the problem? BTW, it seemed like I was running out of gas, but it took a long time to stop the engine and my gauge says three-quarters of a tank and accelerator pump is pumping.
the 65 gs has a plug in unit on the drv fnder. the plug in would get dirty and have engine spits/sputters. cleaned the contacts and back to normal. drove me crazy. happen to rub it and that was the issue. cant recall 300 wiring.
My thoughts are to check the voltage at the coil positive terminal. It should be something between 8 and 11 volts. You can temporarily run a 12V jumper to the positive coil to see if it will run but constant 12V will eventually destroy the points. Then check resistance across the two coil terminals. If it has excessive resistance OR shows open, your coil might be heating up and failing. I had one go bad and it was similar to this. If it cools down and works for a while, that's another sign. If all that checks out, with the coil wire off the distributor and close enough to arc to something metal, turn the ignition to run and ground the coil negative to see if it will arc. That should be the biggest culprits. If you have a tach, disconnect it to remove it being shorted/grounded and causing any issues.
Loose connection(s) on the + and - to the coil. Loose coil high tension from coil to distributor. (the coil wire), points dirty/sticking, distributor cam block on the points worn. (all of these lead to to short point gap, and will degrade spark to the point the ignition starts breaking up and finally stops) and any of these can manifest in a car running fine and then rapidly going downhill on ignition. You mentioned "new fangled" points. Do you mean a "points-to-electronic ignition conversion"? If so, a failed sensor can also result in such issues, but most of the time they just hard fail. A coil overheating can also create issues, but will resolve after cooling down, unless the coil is damaged, but most times the coil will "hard fail" if overheated.
That sounds just like a points and condenser failure. I had a set eat themselves up much like that with similar symptoms. Greg
Cracking up as Adam and I just had this conversation...I'll be replacing points and condenser. It starts so well and timing is great so I was not thinking along those lines at all.
Motor turns over and rotor turns. I have power to the coil when ignition switch is on. Rotor is aimed at number one plug wire terminal when at top dead center. I swapped the coil and condenser for one off an old 401 and that didn’t help. The new fangled points are the ones with the condenser as part of the points. I reinstalled the coil and bought a replacement set of original style points and condenser. Turns over but does not try to start. I can’t see the points to determine if they are opening, or are always open. I ordered a set of mirrors from Amazon that will arrive tomorrow, then I should be able to see the contacts and get a basic gap. Then I will adjust with dwell meter if engine runs. My guess is that the original condenser probably has an internal short that caused the problem. The points looked used but not pitted. I’ll update this post after I receive my new little mirrors.
With the lights off (dark garage) and the cap off you should be able to see the spark at the points as it cranks. Do you have a dwell meter?
The mirrors arrived and I had it running in a few minutes. The points were not closing. Skylark now runs. So the problem was the points or condenser. The odd thing is the points looked a little rough, but no pitting. Back in the day I would have polished them with a new dollar bill and expected them to work. I didn't bother with trying to reuse the points, just installed original style points and condenser and it now starts right up. The Skylark doesn't seem to have as much low speed power as before, but I will start a new thread with that concern. Thanks for all the replies to my questions about the engine not running!
I like the "Standard Ignition" brand for points as they seem to be of a higher quality than others I have seen. The Uniset thing is a non starter(pun) for me as well.
I have reset the dwell to 30 degrees and the timing to 2.5 degrees. After Greg responded to my new thread with a recommendation to increase the timing to around 12 degrees I am going to try that and see if the snappy throttle response returns. I think it will.
Be aware that changing dwell changes timing… so if you have to move your dwell at all, recheck timing. Changing timing does not change dwell, though.
You need to confirm that as the rpm goes up so does the timing from the base line idle setting . If it does not advance with increasing rpm then the center shaft ( mechanical advance shaft) in the Dizzy is hung up from old dried up grease. This timing check is done with the vacuum advance unhooked and plugged. The opposite of this can take place also in that the mechanical advance can get stuck in the full advance position and I have seen motors hammer themselves apart from that , or the owner dials the timing back so far to get the motor to crank when hot that the motor will no longer idle.