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Vapor lock

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Humdog

Freshman Member
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Here's a new question on an old topic. I have a 57 BN4 Longbridge with vapor lock. I have a new fuel pump, I have insulatedy fuel lines and I still get vapor lock when the temp gets about 190. If I'm stopped and then take off the car runs rough until it works it's way out.
Any suggestions?
 
Just curious, how do you know it is vapour lock? Do you get black smoke when it is running rough? Does the fuel pump run madly when it happens? 190 isn't very hot.

Andy.
 
Maybe my last experience could help you. In my Triumph I had the same problem than you. I suppose It was due to the vapor lock but finally I discover that the problem came from my electrical coil which disturb the ignition where getting hot. Finally after changing It, my problem was resolve.
Hoping It could help you ....
 
I used to own a WW2 Willys jeep and once when the temp was very hot it suffered from vapour lock. (The fuel lines run right in front of the engine block)
I asked a few people about this and I was told that during the war, it was common practice to mix petrol with a little parrafin and this would reduce the vapor lock problem. (not suggesting you try this)
 
Had vapor lock on my previous V-12 Jaguar. It would "run out of gas" and after setting for 10 minutes with the bonnet up would start up and run fine.

Issue for me was too much alchohol in the gas that would lower the boiling point causing the problem.

After switching to SUNOCO (no alchohol)..never had the issue. Once in a bind I put regular gas in and sure enough I could be seen on the side of the road stuck.

Pete
 
57 BN4 is correct the fuel pump will act like there is no gas...Mine only did it on days over 90 degrees outside temp.
 
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