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Old 10-12-2017, 07:38 AM   #1
sgt1022
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Possible vapor lock problem

I have a 71 c10, 350 gm crate and motor with edelbrock 1406 carb. I run a Quick fuel electric pump with pressure regulator set at 5 1/2 psi. I have been experiencing pressure drops in the afternoons when its hot while in traffic. Once i start moving pressure goes back to normal. Would a return style revulator help with problem? Would running 93 octane help?
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Old 10-12-2017, 09:07 AM   #2
geezer#99
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Re: Possible vapor lock problem

Heat soak problem maybe.
Do you have a heat spacer?
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Old 10-12-2017, 09:11 AM   #3
sgt1022
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Re: Possible vapor lock problem

Yes, I have a 1 inch plastic carb spacer.
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Old 10-12-2017, 09:14 AM   #4
sgt1022
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Re: Possible vapor lock problem

My pump is inside framerail. Exhaust is routes outside framerail. Braided steel line routed from framerail straight up fire wall to regulator then to carb. Regulator is mounted almost level with carb
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Old 10-12-2017, 09:30 AM   #5
geezer#99
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Re: Possible vapor lock problem

Is it a liquid filled gauge?
They go wacky with heat.

Does it just keep running like normal when the pressure drops?
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Old 10-12-2017, 10:16 AM   #6
sgt1022
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Re: Possible vapor lock problem

No, gauge is autometer sport comp. Yes runs normal when pressure drops it hasnt shut down on me yet. I try to stay moving and limit time at idle
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Old 10-12-2017, 10:39 AM   #7
geezer#99
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Re: Possible vapor lock problem

I guess you might try a return style reg.
Electric pumps don't like to be dead headed.
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Old 10-12-2017, 10:52 AM   #8
sgt1022
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Re: Possible vapor lock problem

I was trying to determine best course of action. Return style regulator or switch back to mechanical pump
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Old 10-12-2017, 08:11 PM   #9
74baggedbug
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Re: Possible vapor lock problem

Make sure that the fuel line isn't close to the headers.. I had that same problem.. we insulated the line where it was by the headers and stopped my vaporlock issue
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