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Tue Aug 26, 2008 6:32 am

Good Morning All,

Can anyone explain in layman terms what exactly is vapor lock? What is happening when this occurres? And what can I do to remedy this condition. I own a restored 72' coupe. rebuilt engine, Solex Carburator and I believe i'm experiencing this condition.
Thank You,
john748

Tue Aug 26, 2008 7:01 am

In laymen's terms, the fuel vaporizes in the fuel line from heat. On a stock engine, its usually a result of the fuel line in the wrong location near something that is hot.

With the heat generated by an ACVW, its critical to minimize heat. Make sure your line is in the correct location and everything is set right - timing, valves, etc.

What excatly is the problem you are experiencing?

Tue Aug 26, 2008 10:29 am

Good Morning Nova,

When I drive my 72' coupe for short distances ( 5-10 miles) I have no problem starting back up. However, when I drive for longer distances (25-30 miles) at a higher sustaned speed (65-70 MPH) I have to turn the ignition four or five times before it will start and this is after letting the car cool down for about twenty or thirty minutes. Does it sound like vapor lock to you?

Thanks,
john748

PS - Thanks for the excellent explanation

Tue Aug 26, 2008 11:16 am

Are you keeping your foot to the floor while cranking the engine during restart? If not, it could take that many tries to get it to restart.

Its the VW recommended procedure for restarting a hot ACVW engine.

Tue Aug 26, 2008 5:41 pm

I do when I start for the first time of the day. Not sure if I did after driving for a while then stopping. I will remember to do this and see what happens.

Thanks Nova,
john748

Tue Aug 26, 2008 5:58 pm

NOVA Airhead wrote: Are you keeping your foot to the floor while cranking the engine during restart? If not, it could take that many tries to get it to restart.

Its the VW recommended procedure for restarting a hot ACVW engine.

That's interesting, I've had to do that. Is it normal to release a big puff of rich smelling exhaust? I started my car hot the other day at a party, and my friend said it stunk up his whole house.

Tue Aug 26, 2008 6:51 pm

It could run rich when first starting from heat soak in the carb. There is a lot of fuel and vapors when it fires up after being hot.

First start of the day should just require a pump of the accelerator and then don't touch it until it fires.

From the '71 manual. I think its pretty much the same for most later model Ghias:

http://www.thesamba.com/vw/archives/manuals/8_70ghia/28.jpg