74 will not start when HOT

[Rubybug]

Good morning, Our 74 super will not start when HOT. It is an auto stick. When the key is turned and car is HOT no sound at all from starter or solenoid. Once cooled off it starts perfectly again. Can the neutral safety switch be susceptible to failure due to heat? What else could cause this?

We are new to the automatic group even tho having the car since 1974.  My wife loves her little autostick convertible.  We are both 76 years old. 

My contact info assuming it is allowable to post,   dsmith1961@protonmail.com

[Raymond73]

Some people have issues with rod that sits under the mechanical fuel pump. Here's a video that might help

[Rubybug]

Thanks for the reply.  But,  the car has an electric fuel pump.  What about the starter??

[Raymond73]

Interesting. I wouldn't think there would be a heat related issue with the neutral safety switch. It's a good distance from the engine so you could have a second issue with the wiring or ground in that circuit. A frayed wire can sometimes cause similar issue. 

Another thought is the shifter alignment. It may not fully be in neutral following a drive. Playing with the shifter might be just enough to fully put it neutral and you'll typically verify the shifter is in neutral during a fresh start vs parking after a drive as you are walking away from the vehicle. Just trying to rule out a mechanical issue.

The starter/solenoid would overheat after constant cranking, but it doesn't sound like your issue if it starts up without a problem when cold. If there is a wiring issue and the solenoid is sticking when the key is in the run position there could be a problem with the ignition switch, the wiring to the starter, or within the solenoid.

The gear on the end of the starter could also be sticking. It's supposed to disengage when the ignition key is let go, but could be spinning with the engine the whole time and only letting loose after a short time.

Difficult to say really. I'm sure that someone more experienced will come along shortly. You can also try TheSamba.com as well. Huge community of people over there. 

[Rubybug]

Okey dokey,  here is where we are.  Saturday I put the new starter in that I got from Jbugs.  Sunday I drove it to Church,  started perfectly after Church.  Then we drove 18 miles to the restaurant,  ate,  came out started perfectly.  Sunday afternoon took it on several errands in over 100 degree heat.  Started perfectly after each stop.  So now I am thinking the crusty rusty starter from 1974 may have been the problem.  Thanks

[Raymond73]

Excellent. Glad that you were able to resolve the issue.

[Rubybug]

Tried to take Ruby to Church this morning.  Sound of silence when I turned the key.  No solonoid, no starter, nothing just like the original complaint BUT engine not hot this time.  yes,  Battery has full charge.  So we are back to unknown problem.

[bhartwell59]

I had a problem like this on my '74 Ghia...when hot (and sat for 30+ minutes) it wouldn't start. No clicking or anything, nothing. After cooling off for 2+ hrs it would then start.

Replaced the ignition switch (electric part) and that seems to have cured the issue... so far!

GL

[Rubybug]

I did replace the ignition switch and the problem persisted.  I have connected up permanent wiring with a push button starter and the problem has gone away,  I think.  Obviously this is a band aid but the car runs and drives perfectly.  The real problem has to be in the old wiring between the switch and end destination,  the solenoid. 

[tmea]

This will likely solve your problem. It fixed mine.
https://www.jbugs.com/product/WR-1.html?utm_content=shopping&gclid=CjwKCAjwo9unBhBTEiwAipC110X3B1nrjFukyK_PMdg-9hfgaabL6o0QJEHod24j9qQaYK7Ok-IubBoC1bcQAvD_BwE