Continuous Fuel Flow After Disconnecting Fuel Line Connector

[1947verns]

In preparation for dropping the engine out of my 1998, the fuel line connector was disconnected as was instructed in the "101 Projects for Your Porsche Boxster" and "The Porsche Boxster Service Manual". It notes that a small amount of fuel would leak. In my case there has been 3 gallons and it was still draining. I had to reconnect the connector to stop the fuel from flowing. Prior to disconnecting, the battery cables were disconnected, the C4 fuel fuse was pulled and the gas cap was on then taken off to see if that had an effect. Nothing slowed the fuel from flowing. What am I missing? Any ideas as to what is causing the continuous flow of fuel?

[Loren]

Always plug the fuel line after disconnecting it. Use a clean plug or clamped shut hose. Just plain good practice.

[JFP in PA]

10 hours ago, 1947verns said:

In preparation for dropping the engine out of my 1998, the fuel line connector was disconnected as was instructed in the "101 Projects for Your Porsche Boxster" and "The Porsche Boxster Service Manual". It notes that a small amount of fuel would leak. In my case there has been 3 gallons and it was still draining. I had to reconnect the connector to stop the fuel from flowing. Prior to disconnecting, the battery cables were disconnected, the C4 fuel fuse was pulled and the gas cap was on then taken off to see if that had an effect. Nothing slowed the fuel from flowing. What am I missing? Any ideas as to what is causing the continuous flow of fuel?

It is called a "siphon".  We always capped the line to prevent this.

[1947verns]

Guys, thanks for your comments. What would you recommend as a good plugging, capping mechanism and material?

[JFP in PA]

21 minutes ago, 1947verns said:

Guys, thanks for your comments. What would you recommend as a good plugging, capping mechanism and material?

 

We have a collection of various size rubber caps that are fuel resistant that we use for this and other temporary purposes such as capping brake lines to keep the system from draining:  

[1947verns]

Thanks for the recommendation.

[DelaveagaSC]

Siphoning is happening. Open the fuel cap and apply a small amount of compressed air on the fuel line going back to the tank with a air gun with a rubber end. That’ll push the fuel back and than your siphoning issue is gone.