Fuel Vapor Separator
Racer
Joined: Feb 2004
Posts: 253
Likes: 0
From: Athol NY
Re: Fuel Vapor Separator (Simul8)
Is your's missing? I don't think there is much to go wrong with them. If you plan on using your charcoal cannister, then I would leave it. Otherwise I'd just plug the line coming from tank to seperator. I believe it just keeps liquid fuel from getting into cannister, and subsequently ruining it. I've seen them at Carlisle for around $20 used. :thumbs:
Team Owner
Joined: Jun 2001
Posts: 23,363
Likes: 1,059
From: Virginia USA
Re: Fuel Vapor Separator (Simul8)
1971 fuel system is a closed system that is why we don't have vented gas caps. I believe the fuel system may not work correctly if you plug the holes because the gas tank is vented through the canister and back into the carb. You may have fuel starvation issues (I may be wrong and I hope someone who knows this better will answer). The fuel separator is to keep raw liquid gas for going to the charcoal canister and also a check valve to keep gas from leaking in the event of a rollover. I'd leave it if it still works. This part is not reproduced by anyone and they go for $100 to $150 used. Good luck
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
Re: Fuel Vapor Separator (theandies)
1971 fuel system is a closed system that is why we don't have vented gas caps. I believe the fuel system may not work correctly if you plug the holes because the gas tank is vented through the canister and back into the carb. You may have fuel starvation issues (I may be wrong and I hope someone who knows this better will answer). The fuel separator is to keep raw liquid gas for going to the charcoal canister and also a check valve to keep gas from leaking in the event of a rollover. I'd leave it if it still works. This part is not reproduced by anyone and they go for $100 to $150 used. Good luck
Really I expect if you run a vented cap you could get away with just plugging this vapor separator hole/tube. But may not be emmisions legal. And I think '71 did use a vented cap were my '74 is not and that separator is the only vent path. :yesnod:
Team Owner
Joined: Jun 2001
Posts: 23,363
Likes: 1,059
From: Virginia USA
Re: Fuel Vapor Separator (cardo0)
1971 fuel system is a closed system that is why we don't have vented gas caps. I believe the fuel system may not work correctly if you plug the holes because the gas tank is vented through the canister and back into the carb. You may have fuel starvation issues (I may be wrong and I hope someone who knows this better will answer). The fuel separator is to keep raw liquid gas for going to the charcoal canister and also a check valve to keep gas from leaking in the event of a rollover. I'd leave it if it still works. This part is not reproduced by anyone and they go for $100 to $150 used. Good luck
I was able to repair mine on my '74. And yes as said they are not reproduced and are expensive even used. But hey, I wouldn't stop looking for a '71 or even corvette specific vapor separator. I don't think size is important here and if you could find one on an import in the boneyard no one will be able to see it to tell the difference.
Really I expect if you run a vented cap you could get away with just plugging this vapor separator hole/tube. But may not be emmisions legal. And I think '71 did use a vented cap were my '74 is not and that separator is the only vent path. :yesnod:
I was able to repair mine on my '74. And yes as said they are not reproduced and are expensive even used. But hey, I wouldn't stop looking for a '71 or even corvette specific vapor separator. I don't think size is important here and if you could find one on an import in the boneyard no one will be able to see it to tell the difference.
Really I expect if you run a vented cap you could get away with just plugging this vapor separator hole/tube. But may not be emmisions legal. And I think '71 did use a vented cap were my '74 is not and that separator is the only vent path. :yesnod:
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
Re: Fuel Vapor Separator (theandies)
I know for a fact that my cap is not vented. This is also before the filler neck size was changed so you could not put leaded gas into an unleaded car. I can drop a baseball in my tank if I wanted to.
Melting Slicks
Joined: Nov 1999
Posts: 2,372
Likes: 227
From: N Cal
Re: Fuel Vapor Separator (cardo0)
I have a 72 Vette that I removed the fuel canister on and plugged the line from the tank. I also purchased a vented gas cap which fits perfect. The gas caps from 68 thru 72 are the same diameter.
:cheers:
:cheers:
Team Owner
Joined: Jun 2001
Posts: 23,363
Likes: 1,059
From: Virginia USA
Re: Fuel Vapor Separator (l2vette)
Here is the gas cap I have. I think that LT-1's came with vented gas caps and base 350's didn't. As you can see it says "sealed" on it which leads me to believe it is not vented.
The Zip web site has 2 gas caps for 1963 thru 1974's also says that either one can be used. Now I am really confused :crazy: oh well I know my separator and gas cap work good. I just replaced my gas tank a few months ago.
The Zip web site has 2 gas caps for 1963 thru 1974's also says that either one can be used. Now I am really confused :crazy: oh well I know my separator and gas cap work good. I just replaced my gas tank a few months ago.
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Safety Car
Joined: Sep 1999
Posts: 4,930
Likes: 11
From: AnyTown NJ
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Re: Fuel Vapor Separator (theandies)
Here's a pic of my cap also "sealed".
I had a situation 2 summers ago where the gas tank was over filled on a 100 degree day. Later when I parked in my garage I had gas dripping from the line going into the canister......Not fun......I guess the separator couldn't handle the pressure. :rolleyes:
Now I make sure I'm the only one pumping the gas and never over fill.
I had a situation 2 summers ago where the gas tank was over filled on a 100 degree day. Later when I parked in my garage I had gas dripping from the line going into the canister......Not fun......I guess the separator couldn't handle the pressure. :rolleyes:
Now I make sure I'm the only one pumping the gas and never over fill.
Le Mans Master
Joined: Oct 2001
Posts: 5,943
Likes: 3
From: Wildwood IL
Re: Fuel Vapor Separator (l2vette)
I have a 72 Vette that I removed the fuel canister on and plugged the line from the tank. I also purchased a vented gas cap which fits perfect. The gas caps from 68 thru 72 are the same diameter.
:cheers:
:cheers:
Eddie
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
Re: Fuel Vapor Separator (gq82)
OK, tell you what's going on, there is a little float ball inside the vapor sep....and its going to float on up to the top and seal the hole IF the fluid forces it to....otherwise it's supposed to stay on the bottom and allow vapors to go through to the canister....thing is...when tank is full or you take a good hard right turn, fuel closes that hatch, then the tank is getting warm fuel from the pump return line, causing positive pressures in the tank, keeping the evap line closed...ball on top, then the tank gets positive pressure I have experienced this much more than typical I think because my recirculation problems are much increased from adding TPI injection....the amount of fuel recirculating to the tank is greater, far far greater....so the possible solution is maybe putting my regulator back at the tank, next to the pump, recirc back into the tank there, and just putting the same 3/8 line to the engine direct with NO return....and using the 1/4 inch return line for the vacuum to the regulator....
allways, something....then there is the lo tank fuel slosh/engine starve problem....which may be helped by a rear mounted regulator...not sure...
GENE
allways, something....then there is the lo tank fuel slosh/engine starve problem....which may be helped by a rear mounted regulator...not sure...
GENE
