Fuel filling problem

We have a Krogen 42' Silhouette 1987. It is new to us and we are have a problem filling the center fuel tank. There is a Y valve after the filling inlet and no shut off valves for either tank. The aft tank fills but that leaves the center tank empty.
No manuals or diagrams came with the boat. Please help!!

Hi Pattey

Welcome to the site. I just looked up a bit of info on your boat. Very interesting version of a Krogen. One of only 16.

Actually - it is somewhat challenging to answer without photo's or more information. If there is an actually Y-valve on the fill tube, this can be diverted either way. If it is just a Y-fitting (not a valve) then it is always open. Are both tanks at the same level? Is there a fuel transfer system?

A bit more info will ensure you get the correct answer on the forum.

btw - are you from Bremerton Washington, or Australia?

Check for a sag in the fill hose to the tank.

Sounds like the centre tank may be a 'DAY' tank which is not meant to be filled directly from the fuel vendor hose.

If I'm even close it is meant to be filled from the other two tanks through a filtering system so what ever fuel is put into the day tank is cleaned by those filters. That way even if the main tanks, the primaries, are contaminated the day tank will allow you to run on cleaned fuel.

If that is the case then look for a fuel pump, fuel filters and valving that does not lead directly to the engine but rather to that centre or day tank.

This is often done by the original owner or for the original owner and may not have been part of the normal equipment.

Yes, some photos, clear ones, may help get some better answers.