GE Washer won't spin

It fills agitates and drains fine it just wont spin in either wash cycle. I’ve checked the lid switch - it stops agitating when lifted.
checked the water level switch tube - blew thru it - clear.
There is a box that the tube attaches to on the outer tub it appears to have gunk in it. Can this box be removed from the outside and cleaned or do I have the problem elsewhere?

Thank You
Dave