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gas cap question

  • Thread starter Thread starter 66newbie
  • Start date Start date Nov 25, 2005
6

66newbie

New Member
Jul 15, 2005
84
0
0
Nov 25, 2005
#1
  • Nov 25, 2005
  • #1
I replaced my tired looking gas cap with a new one. The old one was very loose and I never really paid it much attention. The new one fits really snug and that's great. The old gas cap was missing the rubber seal. Now the engine seems to be a little sluggish now. My thoughts are to check fuel pressure and then maybe adjust the carb if the pressure is fine. Any thoughts ? moneypit if you read this before we cross paths at work give me a call.
 

pabear89

Active Member
Apr 15, 2003
2,126
0
46
High in the Hills of So Ca with the Voices in My H
Nov 25, 2005
#2
  • Nov 25, 2005
  • #2
Did you get one that IS vented?

If not you can and will collapse the tank.

Just ask my Nephew......

PB
 
6

66newbie

New Member
Jul 15, 2005
84
0
0
Nov 26, 2005
#3
  • Nov 26, 2005
  • #3
pabear89 said:
Did you get one that IS vented?

If not you can and will collapse the tank.

Just ask my Nephew......

PB
Click to expand...

How do I tell the difference The reason I got this one is because my garage stunk of gas. With this cap I get no fumes at all.
 

fvike

Member
Aug 24, 2004
335
0
16
Mosjøen, Norway
Nov 26, 2005
#4
  • Nov 26, 2005
  • #4
You'll notice when you can't start the car because vacuum is greater in your gas tank than in your carburetor. I experinced that this spring, because I replaced the leaky cork gasket with a rubber one on my pop-open gas cap. Easy fix dough, just had to slit a 1 mm wide trench in the gasket.
 

mdjay

Premium Sponsor
Dec 9, 2003
896
0
16
Las Vegas, NV
Nov 26, 2005
#5
  • Nov 26, 2005
  • #5
What kind of cap did you get?

The vented caps have a little hole in the center of the inside like the one at the top of this picture.

http://www.mustangdepot.com/OnLineCatalog/images/Fuel/215488F-a.jpg

You can generally replace the cam to a vented one or just exchange for the vented one.
 
6

66newbie

New Member
Jul 15, 2005
84
0
0
Nov 26, 2005
#6
  • Nov 26, 2005
  • #6
I checked and it does have that little hole, so I assume it's vented. Maybe it's just me but it does seem a little more sluggish on take off. It could be the weather though, it's alot cooler than when I normally drive it.
 
L

limey66

Member
Sep 23, 2004
408
0
16
Northampton, England
Nov 28, 2005
#7
  • Nov 28, 2005
  • #7
Cold air should make it run stronger. Pop the cap open, and tape it up so it doesn't chip your paint, then run around the block and see if it makes a difference. If it does, you need a vented cap.

If you have a full tank of gas, and you do a good launch you'll be sloshing fuel all over the road, so take care.
 
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