Mike,
I doubt that your problem is vapor lock or starvation. There should be an
overflow pipe on the top of each float bowl that runs down the side of the
block and ends next to the oil pan. Be sure that there is no fuel leaking
out of these pipes. If they are leaking you have a bad carb float, or the
needle/seat in that arb is worn.
Another way to check the float level is to remove the dome and piston from
each carb. Pull the choke knob out and look down into the jet. The fuel
level should be just below the top of the jet. If it is running over, you
have too high a float level.
Give that a try and let us know hwat happens.
Peace,
PAt
- Support Habitat for Humanity, A "hand up", not a "hand out" -
Pat Horne, Network Manager, Shop Supervisor/Future planner, CS Dept,
University of Texas, 1 University Station C0500,Austin, Tx. 78712-1188 USA
voice (512)471-9730, fax (512)471-8885, horne@cs.utexas.edu
On Mon, 28 Apr 2003, Napolean Dynamite wrote:
> Hello,
>
> I have been dealing with an apparent vapor lock problem for two years now
> and it is getting worse, so I figure it's time to really find a fix.
>
> Here are the symptoms:
>
> On warm weather days (last year it was anything above ~82F), after driving
> for 10-15 minutes and stopping the engine, upon re-start of the car the
> engine does not appear to be receiving enough fuel, as demonstrated by the
> sputtering and loss of power. I can continue driving, but it takes me a lot
> longer to get where I'm going (and its embarrassing when in traffic!). The
> apparent fuel starvation continues and eventually gets less troublesome
> (especially when I get into 4th gear - perhaps a function of the speed I'm
> going and the effect of wind cooling the engine??), although it does not go
> away until the car has had a chance to sit for at least 45 minutes. This
> year the problem occurs in lower temperatures (happened today in 70F), and
> it seems to come on more quickly.
>
> Another symptom is that the car has a strong odor of gasoline (stronger to
> my wife than to me) after driving - even in cooler temperatures when I don't
> experience the vapor lock problems.
>
> Otherwise, the car runs great.
>
> Some observations:
>
> To my untrained eye, the fuel lines look fine. They are not even warm to the
> touch from the gas tank all the way to the carbs.
>
> The fuel pump is operating at about 3.25 PSI at about 800RPM. This is below
> the pressure specification range of 3.41 to 4.26 PSI at 700RPM, but my
> reading could be off due to old testing equipment. Is this a significant
> enough difference to be the problem?
>
> Last year I replaced the fuel pump diaphragm due to a tear which caused fuel
> to leak out the bottom of the fuel pump. There is no apparent leak anymore,
> so I assume that the diaphragm is fine.
>
> The volume of fuel delivered by the fuel pump is sufficient. If anything it
> delivers too much fuel. Could too much fuel being pumped cause this type of
> problem at higher temperatures?
>
> The carbs do not appear to be running hot (touch test).
>
> The cylinder head is hot to the touch, but the engine does not run too hot
> and the car has never even come close to overheating.
>
> Given the strong odor of gasoline, I am starting to suspect the carbs as the
> problem.
>
> The car is a 68 2000.
>
> Thanks for your ideas and comments.
>
> Mike
>
> [demime 0.99d.1 removed an attachment of type application/ms-tnef which had a
>name of winmail.dat]
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