Can someone tell me for sure?

[CaptSeaCraft]

I am wondering if my fuel pick-up is actually hooked up to my vent and vise versa????Everyone has posted that their vent and fill were on the back end of the tank.mine is set up with the outboard fuel line being hooked up to the brass elbow by the sender.Is that correct??The vent line is on the front part of the tank.I believe the vent line is getting fuel in it...thus the reason when I attempt to fill it pushes it out of the ventelator and the gas will not go down into the tank.If I hook it all up like this again,will I still have the same problem or should I swap the two now that I have the oprotunity.If you know for sure the correct hook up please let me know.thank you

[Bushwacker]

The vent and pick-up should be much different size fittings! Your fuel pick-up should be on back of tank, since back of tank should sit lower than front, especially if it's a cc boat, since they tend to be a little stern heavy. Should be a brass or stainless elbow threaded into tank; while you're in there, it's worth pulling it to make sure inside passage is at least as big as a fitting for 3/8" dia. fuel hose. (You can fail a powerhead if this fitting restricts fuel flow if you're running pre-mix fuel!) The vent line (which is sized to pass vapor and therefore bigger than fuel pickup) should be about 1/2" or 5/8" diameter and probably welded to tank. It should be on highest point of tank WHEN YOU'RE REFUELING. Sending unit should be in center of tank for most accurate reading. On my Seafari, the fuel fill is at stern on stbd gunnel (fill hose goes into top at rear of tank), so when I'm back there refueling boat in the water, it will list to stbd and be slightly low in the stern. Vent on my tank (still the original tank) is all the way fwd on port side, so it works fine for in-water refueling. If I refuel at a gas station with boat on trailer, the front of tank is lower than stern, and it will overflow before tank is full, so I typically carry 1 or 2 jugs and get gas in them too. Then I top off in water or at home out of jugs with front of trailer raised up. It will typically take at least another 5 gallons if it was full at gas station.

[McGillicuddy]

Blow into the each hose. Or better yet, blow into the holes directly. The one that sounds like its making bubbles is the fuel supply. The other is the vent.

The fuel supply side has a "straw" attached that draws fuel from 1/4" or less off of the bottom; thus blowing air in will cause fuel to bubble. The vent has the opposite need - it purges from the top...

Good luck

P.S. Like Denny said the sizes are different the vent should be larger.
My vent is forward port corner of tank and fill and supply are aft center of tank. I also have a 72 Seafari but the logic Denny mentioned, applies to all fuel tanks

I think you already checked this, but make sure your vent is not clogged by some crap.

Post some pics if you can.

[CaptSeaCraft]

Awesome.....That was the best info.It is definately plumbed correctly.I just finished hooking up everything and installing the new sender unit.The vent was 5/8 hose barb welded to tank and forward.I had a 1 1/2" od stainless u turn made so I could avaoid the kink that was in the original fill line.I am linking to some pictures so you all can see how it ended up.Thank you again for the quick answers....Its assuring to know that it is exactly the way its suposed to be.I could not get to the back of the original bow vent so now theres two..oh well better than another pie plate access and it was in a impossible to get to location.well now its time to scrape of the sealant and fill in the old holes on the deck so I can get everything back together.Cant wait to fill her up regular style!
http://s853.photobucket.com/albums/a...20replacement/

[eggsuckindog]

I suddenly have this issue - I replaced my sender and now have trouble with fueling. I must have moved the vent hose or something, my feeling is when I filled it completely my vent line may have gotten fuel in it and has a low spot - I was going to blow it out from outside just to check that, but the sender is acting goofy so will pull the hatch - before I messed with it no problem ??
Try blowing out the vent line first a little low spot could be holding fuel - I was going to use my little 12V compressor and a noozle with duct tape

[McGillicuddy]

Can you access the vent hose to raise the low spot forcing any fuel back to the tank? Any chance your new sender's float is in the way of the fill tube or that the pump has too great of a flow for your hose and vent to accommodate?