" Is there any problem with using a tee in the fuel feed line on a two line system to fill thru as I am now? "

With a -T-, you are introducing 3 more potential air leak points, rather then a straight line to the Carb. Think about it. Another point is that some people use a filtered clunk. If you use a -T- with a filtered clunk, then you are putting unfiltered gas directly into the Carb line. To filter properly using a filtered clunk, you must use a 3 line system.

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