# 69 gto won't start when hot



## ltcbear (Dec 7, 2011)

My 69 GTO 4 speed starts fine when cold, but not after running awhile, even after it sits for a few hours (and this was during a pretty warm day). Has new battery and new hi-torque starter. It will jump start eventhough the battery shows 12.5+ volts. It also started after I put a trickle charger on for 2 hours. This problem started before I changed the starter, so now I'm thinking I have some other issue. I do hear a click but it just won't catch. Battery cables or solenoid wire? I'm wondering where to start.


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## pjw1967 (Mar 10, 2014)

Having jump-started hundreds of cars during my stint as a tow truck driver in the '70's, I would look at the cables. They can rot internally, thereby increasing the resistance to the point where no current will flow when they are hot. When they cool off they work. Or you can add more amps to the circuit to plow thru the resistance. My '67 had the same problem. The folks who rebuilt it put on Hooker headers. Steel headers give off a lot of heat which would just cook the starter and the cables. As you did, I got high torque mini-starter a number of years ago. But I also got #2 gauge battery cables at the same time. Very hard to work with due stiffness. And I would recommend you get them with connectors ends already installed. You really need to put the car on a lift to get the positive cable installed. Now here in Houston, with the temps running in the 90's till after sundown, I can turn off the Goat and go start it 10 minutes later with no noticeable drop in cranking power. Good luck!


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## rlslavik (Jun 21, 2014)

My 68 was having the same problem after running 30 minutes in the summer in Memphis.
The headers wrap around the starter/solenoid to the point of cooking both.
I'd just open the hood for 30 minutes and it would crank fine.
Had to let things cool off.

After 2-3 starters I decided to kill the heat.

Header wrap is the BOMB.
Insulating tape wrapped around each individual pipe.
I can even touch my pipes with the engine running.
Added a solenoid heat deflector/shield and
the chrome insulating wrap around the starter and 
the issue went away.

Certainly check the wires and tightness first but
if all looks good, do the header wrap.
Not fun to install but killed the issue...


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## ltcbear (Dec 7, 2011)

Thanks for your input. Finally had a chance to troubleshoot with a mechanic friend. We narrowed it down to a voltage drop between the ignition switch and clutch switch. Something is dropping the voltage to about 11 V under the dash. Maybe the ignition switch is going bad. The cables test good, but I still like your idea of replacing them. I may replace the ignition switch, and go from there. Still seems weird to me. This just started a few months ago and I've since replaced the starter/solenoid and battery. Geeze!


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## pjw1967 (Mar 10, 2014)

Word of advice. Do one thing at a time. Find the voltage issue before you change the cables.


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