[Healeys] Possible contaminates in gas tank

[R Phillips]

The other day I was driving my '65 BJ8 on the highway and it happily
performed by any measure.  When I pulled off the highway and made my way to
a traffic light I had to sit through 2 cycles when it suddenly started to
run rough and stalled.  I was able to restart but it continued running
rough and then settled in.  The gas gauge red more than 1/4.  I don't have
a fuel filter and wonder if there might be something in the bottom of my
tank.

So:  Is a filter recommended, if so which one and how does one clean out a
tank?

Thanks for your help.

Ric
65 BJ8