VW Automatic Register

Technical forum => Technical => Topic started by: Rubybug on 21 June 2023, 15:40

Title: 74 will not start when HOT
Post by: Rubybug on 21 June 2023, 15:40
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
Title: Re: 74 will not start when HOT
Post by: Raymond73 on 24 June 2023, 17:34
Some people have issues with rod that sits under the mechanical fuel pump. Here's a video that might help

Title: Re: 74 will not start when HOT
Post by: Rubybug on 28 June 2023, 01:37
Thanks for the reply.  But,  the car has an electric fuel pump.  What about the starter??
Title: Re: 74 will not start when HOT
Post by: Raymond73 on 01 July 2023, 15:16
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. 
Title: Re: 74 will not start when HOT
Post by: Rubybug on 04 July 2023, 02:38
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
Title: Re: 74 will not start when HOT
Post by: Raymond73 on 09 July 2023, 16:53
Excellent. Glad that you were able to resolve the issue.
Title: Re: 74 will not start when HOT
Post by: Rubybug on 23 July 2023, 21:57
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.
Title: Re: 74 will not start when HOT
Post by: bhartwell59 on 21 August 2023, 16:33
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
Title: Re: 74 will not start when HOT
Post by: Rubybug on 21 August 2023, 17:45
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. 
Title: Re: 74 will not start when HOT
Post by: tmea on 05 September 2023, 19:20
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