trouble filling main fuel tank 252G sailfish

[chempel]

I recently purchased a 1993 252 sailfish and have a difficult time filling the main tank sometimes up to 45 minutes for 100gals. I took the floor up and noticed the 1.5" fill hose actually runs toward the stern before turning and heading toward the fill caps. It seems that if the boat is setting on the trailer with a normal slight bow up that the fuel will have to go uphill at that bend toward the stern. I don't see any easy was to re route the fill hose . Has anyone else had this problem and what was the fix.

 

[Harpoon]

I developed this problem on a Parker 25 a few years ago. You don't make any friends at the fuel dock.
The trouble was a clogged air vent. It's remarkable how the salt and scale can build up there. Pull your vent line off the tank and blow outward. If there is an obstruction it will be obvious.

I switched to a Gemlux flush vent.

 

[seasick]

I developed this problem on a Parker 25 a few years ago. You don't make any friends at the fuel dock.
The trouble was a clogged air vent. It's remarkable how the salt and scale can build up there. Pull your vent line off the tank and blow outward. If there is an obstruction it will be obvious.

I switched to a Gemlux flush vent.

Yes, check the vent first as mentioned. In addition if the vent hose was installed with a low loop, it can fill with fuel or even water from splash and that can trip the fuel nozzle. Insect nests in vent lines are also common. Vent hoses should have no loop or preferably a high loop in the run. A high loop is one where the hose actually is higher than the vent fitting connection. That insures that any fuel that gets into it will drain back to the tank and any minor water will drain out. If there is a low spot and liquid gets in it, the air pressure of the fueling may not be enough to move the liquid block and the back pressure is what trips the nozzle
To be sure of free flow, you may need to disconnect the vent hose at the tanks and see if it is unrestricted.
In rare ( and not so rare ) cases, the fill line is blocked, often by foreign objects that got into it.( like bottle caps, paper or plastic seals from additive bottles etc.)

If the fuel nozzle trips quicker when the tank is more full when refueling than it does when the tank is relatively empty, the likely cause is a blocked vent.

I don't know if you have a separate vent or a combo fuel fill. Either type can get blocked.
If the hoses were previously replaced, it is possible that they were not routed correctly. Either one could have a liquid block due to low points

 

[BobP]

No reason to reroute the 1.5 in. Fill lines. The deck fitting is much higher than the tank fitting, irrespective of being on the water or trailer, or hose route. You have a separate vent fitting on the side of the hull, one for each tank, with a high loop inside hull accessible via starboard lower berth partition wall. Can hear the air rushing out of vent when fueling. The main is 152 gals. It's like a hole in bottom of the boat when I'm fueling, wonder where it goes sometimes. Grady used 1.5 in. hoses with the spiral wire I presume it's not crushed at some point. Check where it runs through the main stringer that's a tight radius as I recall. Might has well change out the vent line and blow out the vent fitting, and tank fitting.

 

[seasick]

No reason to reroute the 1.5 in. Fill lines. The deck fitting is much higher than the tank fitting, irrespective of being on the water or trailer, or hose route. You have a separate vent fitting on the side of the hull, one for each tank, with a high loop inside hull accessible via starboard lower berth partition wall. Can hear the air rushing out of vent when fueling. The main is 152 gals. It's like a hole in bottom of the boat when I'm fueling, wonder where it goes sometimes. Grady used 1.5 in. hoses with the spiral wire I presume it's not crushed at some point. Check where it runs through the main stringer that's a tight radius as I recall. Might has well change out the vent line and blow out the vent fitting, and tank fitting.

Yes the deck fitting is higher than the tank but there still could be a section of the run that forms a low loop for example, the hose runs across the tank and then drops below the level of the tank before looping up towards the fill. That would only happen if the hose had been replaced and it was too long necessitating putting the extra length somewhere. Gas will pool in the loop and can trigger the nozzle to shut off