Gas Tank Replacement Issue....

A few weeks ago, I replaced my gas tank (in my signature car) with a used tank. The used tank came with a fuel pump, sending unit and hoses. I replaced the filler neck gasket, fuel filter and basically breezed through the replacement. I now have an operational fuel gauge and the ability to take right-hand turns without stumbling with less than 1/2 a tank of gas.

One problem (I think) and would appreciate the feedback. When I go to remove the gas cap, there is one heck of a vacuum on the system. It is almost diffucult to take the gas cap off. I don't remember this before and I am a little concerned.

My ideas
1 - kinked hose running from the gas tank to the filler neck
2 - bad vacuum valve on the gas tank (on above hose)

Any thoughts????

Thanks in advance.....

ryan218 said:

fuel pump maybe...did you put the vent line back on?

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Yep, vent line is on it.

1991vert said:

the vent would prevent any type of suction. the filler neck just goes into the side of the tank and that's it. only other place for air to get in/out is the vent. so unless the vent is plugged, dunno what to tell ya. also the filler cap doesn't have an o-ring seal so air should, technically, be able to escape there as well

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That was my line of thinking. It looks like I will drop the tank again and check the tank connection (some type of valve) and the line itself. I really should just replace the old stuff with new while I have it down.

Thanks guys!