Won't start when hot

[scottsbugged]

I have a 72 super. Starts right up runs great no problem, but when I shut it off won't start back up. I can drive as long as I want if I don't turn off. Cools down starts up first try. Why??

[Brian]

Fairly common. Heat makes things expand, also if the carb is too hot the choke wont close. It's recommend that you hold the accelerator down while hot starting.
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Wash your hands

'69 Bug
'68 Baja Truck
'71 Bug
'68 Camper

Only losers litter

[Eric&Barb]

How does it not start??

Very slow cranking? No cranking?

When engine is cold it has not as much compression as when warmed up
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[scottsbugged]

Sounds like normal engine cranking just won't start. I read that this could be a sign of the fuel pump getting bad?

[GJ780662a]

Could be vapor lock - your heat exchangers or heat risers can be causing the fuel in the lines to vaporize. When it won't start, try pouring some cool water over the fuel pump. If that's it, temporary fix could be to wrap fuel lines in aluminum foil. Permanent fix would be to rout fuel line further from heat exchangers and risers.

[Kansas Rob]

No spark or no gas.

You should be able to use started fluid or a little gas to prime the carb next time to eliminate the fuel pump or vapor lock option.

Same thing happened to me and I jumped through all of the vapor lock drama.
Turns out it was a weak coil.
They get old and don't work as well when hot.
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1968 Beetle
1969 Westy

[Eric&Barb]

Or too much gas due to fuel expansion and dripping down the carb into the engine.

Or weak voltage to the coil during starting.

Or even the carb accelerator nozzle not spraying enough.

Seen the above and much much more.

Would try a full tune up first and check carb for above. Then check voltage
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[Tim Donahoe]

I had an H30/31, coupled with a Bosch 034 SVDA distributor. It would start fine when the engine was cold, but was hell when the engine was warmed up. Flooding seemed to be an issue when hot starting, too.

The fix: I got a Solex 34 PICT 3 off The Samba Classifieds and Volkzbitz re-made it for me.

So, I ended up with the proper carb for the distributor I had, and a car that starts well, no matter what temperature the engine is.

Of course, I start it per The Owner's Manual, according to the temperature.

I also got vapor lock on a 114 degree day, but moved my fuel line off the manifold, using a clothespin (I got a new fuel line, also, but won't install it until I pull my engine this fall).

What exactly are your symptoms? And is there a heavy smell of fuel when you have a no-start hot engine?

Tim

[brendo907]

mines kinda goofy like that, i can cold start just fine, shut it off and go into the gas station for a few mins starts right up but 5-10 mins and it cranks alot. starts but i hate being taht guy in the parking lot cranking for awhile to get it to start. Winter project...

[jlex]

Flooding. Hold the accelerator pedal to the floor while cranking (don't pump it!). This will purge the excess gas from the carb...
Many people have trouble with carb'd cars as they're used to fuel injection.
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jlex.
'70 std. "Elsie"
'88 Carrera

[scottsbugged]

Thanks for replies I now have somewhere to start. I'll keep you posted.

[Samer1275]

[[email protected]]

Install a new coil.
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72 Karmann Ghia
71 Westfalia Camper
72 Super Beetle
73 Thing

[DeathTrap]

These guys got vapor lock of the brain

it's either flooding or starving.

Have you ever owned a carburated car before.

poor compression doesn't help either

these little fuel filters plug at the slightes whim of gasohol released slime

never know it till it changed

using the filter as a sight glass to diagnose is wrong

done a tune up lately?

it's not a honda

hold the pedal about 1/8-1/4 down when starting warm.