Good morning, do you need this little valve in the filter when there is an electric fuel pump inside the gastank? Thanks, Robbie
NEVER use a filter with the anti-drain back feature they are too restrictive. Rochester went to solid fuel inlet seats in the mid-1970's instead of the "windowed" variety. If you are having drain-back issues install the later upgraded N/S assembly. They also upgraded the accl pumps about the same time, make sure you are using one with the garter spring under the seal. I put the upgraded N/S and accl pump assemblies in all my rebuild kits, they are lifetime warranty........
Thanks. I ordered the AC Delco GF441 at rockauto. This is not the right one to use? https://www.rockauto.com/en/parts/acdelco,GF441,fuel+filter,6200
Why does it restrict? Because the check valve doesn't get all the way out of the way in the flow direction? How much does it effect flow? I think I've only ever seen the single direction ones.
The filter i ordered AC Delco GF441 at rockauto arrived without anti-drain back feature. Thanks. Robbie
Even if it showed up with the valve a pair of scissors and one quick cut and the valve becomes a gasket instead of a restriction......
Understood. For a factory original engine/carb would this check valve be a disadvantage? Thanks. Robbie
Those check valves didn't show up until the mid to late 1970's, or at least I'd never seen one on any of the early carburetors. By then most of the factory engines were lucky to make 200hp being low compression and loaded down with emission devices. So the valve the filter wouldn't really matter much at that point......IMHO....