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Thu Mar 29, 2007 12:17 pm

I'm having a super fuel flow problem on my super beetle. After my engine warms up and has been driven for a while, if I shut it off and try to restart, I can't. When I look at my fuel filter, (freshly replaced) there is no or very little gas, and bubbles coming up the line from them pump. After about 5 minutes, it fills back up, and if I try to start it as this point, it wont start, and the filter will be empty again. I can only restart it if I wait at least 30 minutes.

Thu Mar 29, 2007 2:00 pm

Could be vapor lock, or sediment in the tank plugging the fuel tank outlet.

Next time it doesn't start, feel the fuel pump. If it's pretty hot, I'd start troubleshooting vapor lock.

If the pump feels OK, open the big brass float bowl drain plug on the side of the carb. If fuel spills out, you can assume fuel delivery is ok, and look elsewhere..

Like carb adjustment, tune-up, possibly a new coil, etc.

Thu Mar 29, 2007 2:47 pm

noexit wrote: I'm having a super fuel flow problem on my super beetle. After my engine warms up and has been driven for a while, if I shut it off and try to restart, I can't. When I look at my fuel filter, (freshly replaced) there is no or very little gas, and bubbles coming up the line from them pump. After about 5 minutes, it fills back up, and if I try to start it as this point, it wont start, and the filter will be empty again. I can only restart it if I wait at least 30 minutes.
:?: Do you have a fuel injected engine or carburated?

Fri Mar 30, 2007 2:57 pm

Your metal fuel line may also be stopped up. Mine was closed almost completely off with dirt, rust, etc. Looked like a clogged artery.

Sat Mar 31, 2007 7:09 pm

Fuel flows great to the pump, and I'm pretty sure the pump works. My local VW shop said that the mechanical pumps wither work, or they don't. The metal fuel line is not resting on anything hot, and I have a new filter.

Sat Mar 31, 2007 8:20 pm

u need to check 2 things. 1 remove the hose where it plugs into the carb. and hold the hose into the carb, have a friend crank the engine. u will have huge spurts of gas flowing into the carb. if u do remove the top of the carb and un stick your float valve.
my filter is never full.it is allways empty, dont worry about it the gas will only flow into the carb if the valve is open

Sat Mar 31, 2007 8:30 pm

noexit wrote: Fuel flows great to the pump, and I'm pretty sure the pump works. My local VW shop said that the mechanical pumps wither work, or they don't. The metal fuel line is not resting on anything hot, and I have a new filter.

Not quite. They can get a buildup of trash in them that gets caught up in the little screen inside. The trash moves in and out of the way of fuel flow causing intermittent problems.... and immense aggravation until you figure it out.
They open up and clean out easily in about 10 min.

Sun Apr 01, 2007 6:03 am

I wonder if your fuel tank venting is plugged. When that happens, unscrew the gas cap and listen if you can hear a bunch of air sucking in. I had this happen once, was getting a partial vacuum in the gas tank, starving engine of fuel. It turned out that a little "tee" fitting in the vent lines in the trunk was plugged with dirt (don't know how), just had to clean that out and re-install.

Sun Apr 01, 2007 11:05 pm

Atl Phil wrote: Not quite. They can get a buildup of trash in them that gets caught up in the little screen inside. The trash moves in and out of the way of fuel flow causing intermittent problems.... and immense aggravation until you figure it out. They open up and clean out easily in about 10 min.

Open the fuel pump? How do I do that? It doesn't look like it comes apart.

The tank vent was plugged, but I've fixed that problem, and still have the fuel problem.

Mon Apr 02, 2007 5:53 am

PM me with an email address and I can email you an Adobe scan of the Bentley manual pages for that.
There were a few different fuel pumps used and I don't know if all of them allow disassembly. They only show one model and it happens to be the one on my 74. My prior 73 had one that looked different, more angular and boxy, but it also came apart.