View Full Version : Anti-siphon valve

10-01-2008, 06:01 PM
I have an 89 Prostar 200 outboard, and need a new anti-siphon valve on the gas tank.
Anyone know what size? Brass or Aluminum?

I don't have access to the boat before I have to show up with the right part.

Thanks for your help

11-03-2011, 11:09 AM
In the process of changing the anti siphon valve on my ProStar200 now. Did you ever change yours? I believe you have to remove the floor panels. Any feedback would be great. Thanks in advance.

east tx skier
11-03-2011, 02:29 PM
Should be brass. Not sure on the size. Not much to it.

12-10-2011, 11:10 PM
I did end up replacing the anti-siphon valve, only to find that it was not likely the problem.
- Engine failing after a high speed run, once in a while
- Squeeze bulb drawn flat
- Waiting a few minutes and running below 20mph, everything fine

Replaced the squeeze bulb, inspected the fuel lines, filters, water seperator, everything fine. Thought at that age, ethanol in the gas could be a problem. Nope.
This led me to think that the anti-siphon valve was the problem. Replaced it, and had no problems for a while.

I now think the problem may be rust or other debris in the gas tank that is clogging up the fuel input line. The motor is starved for gas only once in a while. When it stops, rocking the boat and waiting for a bit and the bulb goes back to normal, the sheet of rust or whatever moves around, and no problems for another 20-30 engine hours.

Changing the valve is not easy. You have to remove the seats and the floor boards, and still it is pretty tough to get at. I replaced the fuel line at the same time, as hose is cheap.

Good luck.