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Thu Jun 19, 2025 4:20 am

My ghia struggles to restart when it’s hot, any ideas

Thu Jun 19, 2025 4:49 am

Use non-additive gasoline E0 or E5 (Premium 98 or 100, depending what you have available in FR), or ETBE additive instead of ethanol. The additives and ethanol boil at lower temperatures, and the engine compartment after shutting off can be 60C or higher, causing vapor in the lines.
Drain any old gas, use gasoline stabilizer.

Make sure fuel lines are away from hot areas (exhaust, motor casing).

Put insulation on fuel lines on suction of pump, to carbs. This will help keep gas in the lines from vaporing off.
https://fmic.eu/30295-silicone-heat-insulation-sleeve-6mm-10cm-section-th-sleeve06-100.html

I am fighting this with modern gasoline also, here in CZ. Adding fuel line insulation changed my fuel pump temperature after shutoff from 65C to 40C.

I also rotated my distributor clockwise (more retarded) just a little bit- about 1mm on the outer edge of the cap.
It turns over much faster now, overcoming the cylinder compression easier when hot, so any empty fuel lines fill faster.
(My car is 6 volt, with high compression engine, so it really needs the extra help).

Thu Jun 19, 2025 5:06 am

Next time you stop the car when it's fully warmed up, quickly get out and remove the air filter neck off the carb, and see if you can see fuel dripping down the throat of the carb.
A fuel pump that puts out fuel pressure that's too high will force fuel past the needle valve, and flood the engine after you turn it off, making it difficult to start when hot. But if you let the car sit until it's cool, it'll have no problem starting because the excess fuel will have evaporated by then.
I had this exact problem on the 67 I used to own. Shimming the fuel pump with extra gaskets brought the fuel pressure down which stopped this from happening.

Thu Jun 19, 2025 7:42 am

Struggling to start how? Like the starter struggles to turn over the engine, or engine turns over as normal but won't fire?