Author Topic: correct vented gas cap  (Read 323 times)

shelbymann1970

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correct vented gas cap
« on: May 02, 2021, 03:27:43 PM »
Does anyone have a pic of the correct vented gas cap and also the Ford number used? Thanks
Shelby owner since 1984
SAAC member since 1991
1970 GT350 4 speed(owned since 1985).
  MCA gold 2003(not anymore)
1969 Mach1 428SCJ 4 speed R-code (owned since 2013)

J_Speegle

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Re: correct vented gas cap
« Reply #1 on: May 02, 2021, 03:33:58 PM »
Did you find this thread when you did your search of the site?

https://www.saacforum.com/index.php?topic=4218.0

Not sure if answers both your questions since these things sort of take different paths once started here but its a quick place to start
Jeff Speegle- Mustang & Shelby detail collector, ConcoursMustang.com babysitter :) and Judge

Bob Gaines

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Re: correct vented gas cap
« Reply #2 on: May 02, 2021, 04:46:05 PM »
Only 69/70 GT500's need the recall it seems and indicated by Ford. The correct non vented caps used back in the day are very hard to find. Of course the non vented gas cap is best . If you do the recall venting described in the recall illustration provided in the link then even if you do only have the vented gas cap that came from the factory the chances of excessive fume build up at the vented cap will most likely be negligible. The pressure/gas fumes is going to take the path of least resistance which in this case is the more open pathway of the venting tube compared to the small venting port on the vented gas cap. 
Bob Gaines,Shelby Enthusiast, Shelby Collector , Shelby Concours judge SAAC,MCA,Mid America Shelby

Bob Gaines

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Re: correct vented gas cap
« Reply #3 on: May 02, 2021, 04:50:59 PM »
FYI if you do add the non vented gas cap you must also do the plumbing for the vent. If the non vented gas cap is used without any kind of additional venting then the gas being sucked out of the gas tank by the fuel pump will not have air to displace it forcing the fuel pump to work much harder and in some cases causing a no run situation.
Bob Gaines,Shelby Enthusiast, Shelby Collector , Shelby Concours judge SAAC,MCA,Mid America Shelby

Special Ed

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Re: correct vented gas cap
« Reply #4 on: May 02, 2021, 10:46:57 PM »
I have plenty of original nos gas caps for the 69 -70 gt350s   but on the gt500s the non vented gas cap is very hard to find and i sent some to chris brown to replate and not all 69-70 gt500s got the recall as this was more of a southern heat belt area that had the heating  problems as my purple car came from northern ohio and never had the  recall done and the assembly  line gas caps are different than service replacements.

shelbymann1970

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Re: correct vented gas cap
« Reply #5 on: May 03, 2021, 05:46:21 AM »
Did you find this thread when you did your search of the site?

https://www.saacforum.com/index.php?topic=4218.0

Not sure if answers both your questions since these things sort of take different paths once started here but its a quick place to start
Thanks Jeff as I dropped the ball and didn't search first. Gary
Shelby owner since 1984
SAAC member since 1991
1970 GT350 4 speed(owned since 1985).
  MCA gold 2003(not anymore)
1969 Mach1 428SCJ 4 speed R-code (owned since 2013)

csxsfm

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Re: correct vented gas cap
« Reply #6 on: May 03, 2021, 08:26:58 AM »
Bob's right about the effect of non-vented cap in the wrong application. Makes the car surge. Happened to me when corrosion plugged the small vent hole in my cap. 

SCJSTU

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Re: correct vented gas cap
« Reply #7 on: May 04, 2021, 10:38:41 AM »
good stuff fellas
Many Fords,Hot Rods,Motorcycles
I just canít make up my mind