Pressure build up in gas tanks. Does your Esprit do this?

[Techspy]

So after my complete engine pull/rebuild/install, I am putting miles on her to break her in. I made my 2nd stop for fuel today and when I opened the gas cap there was a lot of pressure and air (fumes) escaping. I had never experienced that previously. The car is running great and I have had no fuel smell. I have the charcoal canister connected as it should be and replaced the vent hose etc when I had it apart to check the gas tanks conditions. Also, the manifold pressure tube to the canister is T'd into my blow off valve and that is working so I know it is seeing the right pressure.

 

I think I just figured it out! I thought this thing was a filter of sorts,

 

 

It is a check valve isn't it? I bet I have it the wrong way so the canister/vent system is not able to vent the fumes into the manifold.

 

Does this sound correct?

Edited December 16, 2013 by Techspy

[Vulcan Grey]

Yes sounds like your check valve isn't working correctly, or is the wrong way around.

 

I've had brand new check valves like that that didn't work correctly, so test it first.  I also had one that seemed to work correctly, but let a really strange noise through the crank case breather and into the intake assembly.  Was super loud! I replaced it with the old one, and the noise went away.

 

Some pressure in the tanks is normal of course.

[Techspy]

Thanks Travis. I think I can tell which way it is supposed to be in the service manual. I guess I can always blow on it to test.

[Vulcan Grey]

the flow is from the charcoal canister to the manifold. try blowing into the valve with your mouth to see which way.

 

but they are supposed to be like this

 

[Techspy]

Cool, thanks!

[Techspy]

Yep, it was reversed. I imagine that will fix the issue.

 

Thanks

[Vulcan Grey]

check your other check valve from the intake manifold to the green egg at the crank case breather as well.  Should go with the flow from the breather to the intake manifold.

[andydclements]

I had pressureised tanks, but at least you didn't experience what I did: Fuel pushed out of one tank when removing the filler cap.

[Techspy]

Yep, I already checked the other one and it was on correctly.

 

Glad I caught it before it caused any issues! At least I know all fuel tank hoses are secure and there are no leaks!