Fuel Cap Gasket replacement

Moderator: Larry Jowdy

Fuel Cap Gasket replacement

Postby PandaSal » Tue Sep 11, 2018 7:11 am

Hi all,
Just brought home my spyder last weekend. Realized right away gas fume smell in my garage, first obvious to me is that the fuel cap doesn’t seal tight. Anyone know where I can order replacement gasket? This was Thunder ranch kit, but not sure that matters when buying these small parts.
Thanks,
Sal
Attachments
289F55B3-4792-4DCE-9025-9DACB0146F5B.jpeg
289F55B3-4792-4DCE-9025-9DACB0146F5B.jpeg (12.21 KiB) Viewed 804 times
User avatar
PandaSal
Junior Member
Junior Member
 
Posts: 10
Joined: Sat Sep 01, 2018 5:20 am
Location: Bay Area California

Re: Fuel Cap Gasket replacement

Postby Larry Jowdy » Tue Sep 11, 2018 7:25 am

You're better off going to your local auto parts store and buying a sheet of gasket rubber and making your own gasket. Another issue that's forgotten by most new owners of Spyders is the fact that the car isn't fuel injected but rather has 2 carburetors. The Carburetors hold gasoline in their fuel bowls and therefore will smell of gasoline. Fuel Injected engines are sealed and as such, no gasoline smell (unless there's a leak)
Larry Jowdy
Site Administrator
User avatar
Larry Jowdy
Site Admin/Owner
Site Admin/Owner
 
Posts: 8413
Joined: Sat Jun 14, 2003 11:00 pm
Location: Ontario, California USA

Re: Fuel Cap Gasket replacement

Postby albaran » Wed Sep 12, 2018 6:36 am

We get spoiled by modern cars which have sealed fuel systems. I have two carbureted cars, the Spyder and a MGA. They both will have a slight smell of gas when I come home from a trip. The smell is probably, as Larry says, the gas evaporating from the float bowls. I would be careful about sealing the gas cap too much because they are supposed to be vented to allow air into the tank to replace the fuel that is being drawn into the carbs.
albaran
$$Donating Member$$
$$Donating Member$$
 
Posts: 435
Joined: Thu Apr 18, 2002 11:00 pm
Location: Stratford, Connecticut

Re: Fuel Cap Gasket replacement

Postby danstern » Wed Sep 12, 2018 12:36 pm

Stick your nose near any 356 and there's a slight smell of gas. That said I had a similar stronger problem. First I tightened the spring inside the gas cap to make sure my gas cap rubber (which had no tears) was sealing. Then I resealed the sender. Then an extension for the exhaust pipe. Finally I found a slight crack in the tank near the sender and had it welded. (A Gas Co. natural gas sniffer was instrumental in finding the crack.) The car now has just the normal carb car odor.
Dan
Quantum Mechanic, Black Holes refilled, Quarks repaired
Vintage #74, 2109cc
User avatar
danstern
$$Donating Member$$
$$Donating Member$$
 
Posts: 1178
Joined: Sun Jan 11, 2009 4:44 pm
Location: Manhattan Beach, CA

Re: Fuel Cap Gasket replacement

Postby PandaSal » Wed Sep 12, 2018 8:06 pm

Thanks for tips everyone. This being my first classic car, not familiar with what “normal carb car odor” vs being concerned about unsafe level of gas smell. I ordered 1/4 sheets of rubber on Amazon. Will plan to make my own new gasket to replace fuel cap gasket as it’s not closing/sealing very well. I can still depress gas cap about a quarter inch even after it’s locked
User avatar
PandaSal
Junior Member
Junior Member
 
Posts: 10
Joined: Sat Sep 01, 2018 5:20 am
Location: Bay Area California

Re: Fuel Cap Gasket replacement

Postby DannyP » Thu Sep 13, 2018 4:30 am

That's what it's designed to do. There isn't usually a vent hose on Spyder tanks, the venting is done through the cap via a spring. As the fuel level drops, air is let in to fill the space. If air couldn't enter the tank, your engine would starve for fuel as the pump couldn't work against the suction. Conversely, if the fuel expands the vapors need to be let out. This is part of the smell, along with the fuel that evaporates from the carbs.
2016 Vintage
User avatar
DannyP
$$Donating Member$$
$$Donating Member$$
 
Posts: 4198
Joined: Tue Oct 16, 2001 11:00 pm
Location: Wallkill,NY,USA

Re: Fuel Cap Gasket replacement

Postby PandaSal » Fri Sep 14, 2018 12:11 am

Thanks for the info Dannyp!
User avatar
PandaSal
Junior Member
Junior Member
 
Posts: 10
Joined: Sat Sep 01, 2018 5:20 am
Location: Bay Area California

Re: Fuel Cap Gasket replacement

Postby albaran » Fri Sep 14, 2018 10:04 am

Otherwise, you might be going down the road one day when the car mysteriously comes to a stop. You get out to check what could be wrong. You open the gas cap and you will hear this loud whoosing sound as the air rushes into the tank to fill the vacuum in there. Don't ask me how I know this.
albaran
$$Donating Member$$
$$Donating Member$$
 
Posts: 435
Joined: Thu Apr 18, 2002 11:00 pm
Location: Stratford, Connecticut

Re: Fuel Cap Gasket replacement

Postby DannyP » Fri Sep 14, 2018 10:45 am

That's funny, Al!
2016 Vintage
User avatar
DannyP
$$Donating Member$$
$$Donating Member$$
 
Posts: 4198
Joined: Tue Oct 16, 2001 11:00 pm
Location: Wallkill,NY,USA

Re: Fuel Cap Gasket replacement

Postby RBP » Fri Sep 14, 2018 6:38 pm

On my TR the cap didn't seat so it wouldn't seal and my garage stunk like gas. I fixed the cap spring and seal so that it seated tight. It then caused the tank to vacuum a bit so I drilled a small hole through the metal plate to allow some air. Problem solved no more issues.
Vintage, 2316 Type IV
User avatar
RBP
$$Donating Member$$
$$Donating Member$$
 
Posts: 1093
Joined: Sat Apr 08, 2006 6:45 am
Location: Ottawa, Canada


Return to Tech General

Who is online

Users browsing this forum: Google [Bot] and 9 guests