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  • 1965 - 1973 Classic Mustangs -General/Talk-
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Vapor Lock??

  • Thread starter Thread starter grego37
  • Start date Start date Jul 28, 2007
G

grego37

New Member
May 12, 2004
576
0
0
Fresno CA
Jul 28, 2007
#1
  • Jul 28, 2007
  • #1
Took the car out yesterday, its been sitting for a few months with gas in the tank. seemed to run as usual. took my usual route, through the hills , up and down a few streets, and a few miles on the freeway. When I got off the freeway and was cruising down the street, it began to sputter and died, like it had no fuel. I had a good 10 gal. in it. After cranking it over and over for a few minutes, it fired back up and I stumbled home. In the driveway, the fuel pressure was a few lbs low, and the pump sounded very odd, somewhat quieter.

outside temp was around 100*, 175*-195* water temps and 200* oil temps
Normal for my vehicle.

all of my fuel line from tank to carb is 1/2" and has the good fire sleeve on it to protect it from heat etc... I've driven in these conditions before but never experienced this.

I guess my main question is, was this vapor lock I experienced?

Are you more prone to vapor lock if it has old fuel in it??? quality of gas has changed?

I've drained all the fuel since, fired it up, pump sounds like normal, and fuel pressure is back to normal. Have not test driven yet.
thanks
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
6
0
south louisiana
Jul 28, 2007
#2
  • Jul 28, 2007
  • #2
The old gas was "winter" gas and as such generates a higher vapor pressure than the gas being sold now. So you could very well have experienced vapor lock. Take a few gallons out of the tank and put it into a plastic gas can. Then take the same amount and put it into another plastic can. Set them both out in the sun and watch. The old gas will swell it's can bigger than the other.
 
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