Scottishflyer182
Your post is a bit confused. If you have a carburated engine you do not have a fuel flow gauge and the other thing is 'diverter', what is it?
From thefuel pump the fuel flows into the fuel servo which sometime is also called 'injector servo' or 'metering unit' and from there it continues towards the 'fuel distributer' or 'spider',I believe that you refer to this part.
Inside the Spider there is a valve that is attached to a Diaphragm loadedat the top by a spring. The fuel reachs to the underside of the Diaphragm and pushs it against the spring, the valve opensand fuel flows to the cylinder's injectors.
There can be 2 faults that willprevent the spider from fully open.
1. Bridged Diaphragm - The spider has to be opened and the part has to be replaced.
2. The air vent at the top (on the side) of the spider got blocked which prevents the Diaphragm and the valve from opening. In order to remove the blockage you need to push a wax wire into it, NEVER USE A LOCK WIRE as you will cut the Diaphragm.
Good luck