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07-03-2013, 11:09 PM | #1 |
Registered User
Join Date: Sep 2006
Location: Riverton KS
Posts: 832
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Does this sound like vapor lock?
I have been driving my truck with a rubber fuel line running from the pump to the carb. Absolutely no problems, starts right up and ran great. Yesterday I built a new line using -6AN line from the pump to the carb with a billet filter in the middle. Once I was done, I started it and let it run for a while. Started right up and no leaks. So this evening It starts fine and I drive about 15 min to where I was going then shut it off. After about 30 min I get in to leave and it wont start. I have to hold the gas pedal to the floor to get it to start. Once it starts, it runs fine. It will also start right back up once you shut it off. What would changing the fuel line do to cause this. It's routed in the same spot as the old rubber line was. It's cooler here than it has been in the last few weeks, so it's not that its hotter. Does anyone have any ideas? I'm confused.
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07-03-2013, 11:20 PM | #2 |
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Join Date: Jun 2013
Location: Somewhere
Posts: 3,091
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Re: Does this sound like vapor lock?
If you didn't have vapor lock before, no reason to now.
More likely (in my tiny mind) that a bit of junk from taking apart and putting things back together lodged under the needle and seat. |
07-04-2013, 09:25 AM | #3 |
Formerly- 1972SuperCheyenne
Join Date: Oct 2008
Location: Wake Forest NC
Posts: 5,782
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Re: Does this sound like vapor lock?
Try this, put about 6-10 wooden clothes pins on the metal fuel line you just installed. They will dissipate the heat. If its back to normal, find a wrap or something to cover the new metal fuel line or move it further from anything that is getting hot.
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07-04-2013, 10:51 PM | #4 |
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Location: Riverton KS
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Re: Does this sound like vapor lock?
OK. I switched lines back to the old one in the exact location that it used to be. Problem is still the same. So I can rule out the braided line being the problem. I still have to put the pedal on the floor to start it after it is hot and set for over 30 min or so. I am so confused as to why this happened suddenly. I have been driving it alot, and in much hotter weather with zero problems.
Franken- By "Needles and seats" are you talking about the metering rods and jets? (Edelbrock 600) If so, whats the best way to clean or blow the junk out? I"ll try the clothes pin thing too. If anyone has any other ideas or suggestions I am all ears. I really want to figure this out quickly. Thanks for the help!
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07-04-2013, 11:19 PM | #5 |
Junior Member
Join Date: Dec 2006
Location: Southeast Missouri
Posts: 2,436
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Re: Does this sound like vapor lock?
Edelbrock carbs are pretty heat sensitive. They need a phenolic spacer installed under them to keep the heat from boiling the fuel out of th float bowl. I am not sure this is your problem but it is possible.
My son has had to put them under all his vehicles with Edelbrock carbs.
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07-05-2013, 02:51 AM | #6 |
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Join Date: May 2012
Location: California
Posts: 68
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Re: Does this sound like vapor lock?
I had this same problem on my Nova! Simple fix!
get a moroso wood/plastic carb spacer! your intake is basically transferring/heating up the carb too hot and it is causing your vapor lock!! hope this helps!! |
07-05-2013, 09:08 AM | #7 |
Who's got steelies?
Join Date: Feb 2006
Location: Morrison, Oklahoma
Posts: 1,026
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Re: Does this sound like vapor lock?
By needle & seat, he is referring to the float valve where gas enters the carb.
Change your fuel filter & see if the problem goes away. You may have to pull the top of the carb off & clean or change out the needle & seat also. The heat spacer is also a good idea. I used a 1" phenolic 4-hole spacer when I had an Edelbrock carb on mine. Made hot starts much easier, carb stayed a little cooler.
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07-05-2013, 09:19 AM | #8 |
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Re: Does this sound like vapor lock?
What's your choke position when this occurs? On a hot day 30 minutes after driving your choke should be wide open.
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07-05-2013, 09:42 AM | #9 | ||||
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Re: Does this sound like vapor lock?
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Thank you all for the responses. I will try all of these suggestions and report back.
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07-11-2013, 08:25 PM | #10 |
Registered User
Join Date: Jun 2011
Location: Inwood, WV
Posts: 41
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Re: Does this sound like vapor lock?
I had very similar symptoms on mine. The issue I had was with the filter that was in line between the pump and the carb.
If you had a filter in line with the steel line, try taking the filter out and evaluating it. Easy and cheap test. |
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