I installed a new fuel accumulator on my 80' 240. The new accumulator did not come with the small nipple fitting where the fuel tank vent/overflow hose connects.

Parts store said it was not needed and to just let the vent hose hang underneath without plugging it.

Problem is when the tank is full some gas will slosh up and drain out. This always happens on hard right hand turns as the line comes out on the left top of the tank.

Is it actually needed to "vent" the gas tank?
Is it OK to just plug this vent/overflow line?

Thanks,
Dale

Yes do plug it, I was told by my volvo mechanic that it will not effect anything it was just to aid some sort of actuator inside of the older style fuel accumulators but the new ones have a spring or something that does the same job, I just cant quite remember what the reasoning was behind it right now. I did that on my car about 10, 000 km ago and have had no problems, I disconnected the line from the tank and removed it and filled the tip of the connector at the tank with some epoxy.

Hope this helps

Dale,

That is a good question. I would say "yes" as my 79 arrived to me with such a replacement accumulator. Its hose was tie wrapped to the pump tray with a sheet metal screw plugging it and a hose clamp around. Since I noticed that, I learned the vent was a safety measure to allow fuel to be safely kept within the system if the diaphragm leaked, and it made sense the accumulator could not vent the tank.

But, this same car is the only one in my fleet that goes pffft when I pull the gas cap off in the summer. The air quality folks mark the cap as failed when I get it tested, but somehow do not give me any incentive, like a failed test, to do anything about it.

So, I'd say I think you should plug it.
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Art Benstein near Baltimore

re: "...The air quality folks mark the cap as failed when I get it tested..."

It sounds as if you meant that they test the pressure in the fuel tank when they test your cap -- otherwise it wouldn't make any difference whether you plugged the vent line or not.

Here in N.J., they don't do anything with the tank pressure. When they test the cap, they remove it from the car and insert it into a "pressure" contraption on a machine standing nearby -- it tests whether the cap can hold the pressure.

I'm stil using my 20 year old, locking gas cap. When it comes time for state testing, I replace it with a cheaper but new cap -- after the test (I always pass), I put back my original locking cap for the next two years. :-).

Regards.

Hi Ken,

Here they do the same test; check the cap on some gizmo hooked to an air hose with a slew of different colored adapters. The difference, is a fail on the cap does not cause the car to be rejected on the 79. I don't know if it would on a later model. There's no measurement made on the fuel tank itself, except to see if the unleaded fuel restrictor has been removed, using a stick. I still have one of those locking gas caps from the 70's, back when fuel was pricey.
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Art Benstein near Baltimore