[Lawrie]

Henry. the thing you got to fix is the air bubbles going into the glass bowl,at least you can see the problem,
one thing to do is when the engine is running hot and the bubbles are coming into the bowl,take the inlet fuel hose off and block the port with your finger,if the bubbles stop,the problem is down the line some where,if they don't,look at the gasket under the bowl or some other leak in the inlet area of the pump.
Lawrie