[pb101]

Hello,
My 65 is getting temper mental about starting. Never had an issue before even in 100 degree weather. Now if it’s really hot out it won’t start after driving. Also if it’s was sitting for a couple days sometimes when I turn the ignition I get nothing for about 4 tries then it starts right up. The battery tests good. Charging is good. The wiring is new ( about 5yrs old) from M&H. I replaced the solenoid on the starter ( mini starter form Rob Mc) just to make sure but same thing. The car is an A/C car but nothing is connected or in the car.
Can I use a regular ignition switch (6pin) ?
Or if you think there is another problem.
Thank you,
Paul

[60sstuff]

Just from experience in the past and from what you have described.

On a GTO with the factory type starter and solenoid.
When the solenoid gets very hot the contacts inside won’t work until it cools.
On some cars with this situation, you need to let the engine cool before it will start.

The other issue you have about cranking the engine several times before it starts after sitting for days may be evaporation of fuel from the carb.

These are just ideas to consider.

CT

[Goatracer1]

you didnt say whether it is an auto or manual trans. If it is an auto trans have someone check the voltage before and after the neutral safety switch while you turn the key. If you have voltage before the switch and not after when in neutral/park then the NS switch is bad. If no voltage before the switch then the ignition switch is probably bad. Instead of just replacing parts use a volt meter to diagnose problem.

[pb101]

Thank you for the suggestions.
It’s an automatic. I’ll check the switch.

[Chris65LeMans]

Anyone have any diagnosis tips for the same issue with a manual trans? I had this problem bad, and I fixed it with a new under dash harness from M&H, and a new ignition switch. (Someone had fixed the old one with duct tape. I learned later that it didn’t turn right.). Now this problem is beginning to show again...

[John V.]

Best advice is to begin troubleshooting. Intermittent problems are the worst. Especially when related to heat.

There is also a difference between an engine that is cranking but won't start and one that isn't cranking (and obviously won't start).

If my GTO sits for more than a day or two, fuel evaporates from the float bowl and will crank but won't start as the mechanical fuel pump tries to refill the float bowl. After 3 or 4 cranking events (turns of the key and pumps on the pedal), it fires up. Strong battery and good cranking all the while. If the car only sits for 24 hrs after starting, it will fire right up on first turn of the key.

So my "cranks but doesn't fire" events are always related to fuel evaporation.

I read the OP as meaning, "no crank" at all when the key is turned, but only for about 4 tries and only when the ambient temps are "hot". That's pretty exasperating cause you would need to diagnose while it is refusing to crank. Alternate is to throw parts at it and hope to get lucky.

Here are a couple decent reads related to the troubleshooting for a no crank condition.

http://www.secondchancegarage.com/pu...n-checkout.cfm

https://www.hagerty.com/media/mainte...starter-motor/