Anti Siphon fuel line required??

rost495

Petty Officer 2nd Class
Joined
Jul 10, 2005
Messages
109
Need to buy a barb for my boat project for the below deck fuel tank.

2 questions. First there seem to be 2 tubes to " draw fuel from" side by side within an inch or 2. Which one to use. Have not pulled either out...

2nd, a supplier lists normal barbs, but also a coast guard required anti siphon barb. I have a 21" CC that will be going saltwater and into federal waters.

Jeff
 

dingbat

Supreme Mariner
Joined
Nov 20, 2001
Messages
16,313
Re: Anti Siphon fuel line required??

The second output is for use with twin outboards. It really doesn't matter which one you use but I used the one the furthest to the rear of the boat thinking that would be the lowest point in the system while on plane.

An anti-siphon valve is required equipment by law.
 

WillyBWright

Fleet Admiral
Joined
Dec 29, 2003
Messages
8,200
Re: Anti Siphon fuel line required??

It's possible that one tank pickup is higher than the other for a Main/Reserve optional valve, but more likely what dingbat said. Choose the one closest to centerline.

An antisyphon is required in sterndrives, but you can use a straight fitting for an outboard IF the hose routing is such that fuel cannot syphon out if a leak sprouts. In other words, it has to run uphill the entire length and cannot go below the top of the tank anyplace and it must be anchored so that it can't if the line is slack as outboard lines always are. The best way to accomplish this is to run a thick sterndrive-type hose from the tank fitting to a bulkhead fitting in the motorwell and attach your outboard hose to that. The line from fitting to fitting must go uphill all the way. If you just want to attach a regular outboard fuel line straight to the tank, you have to use an antisyphon valve.
 
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