Anti-Siphon Valve Problem?

[Stumedic]

A friend replace his fuel lines with alcohol resistant ones, and at the same time replaced the priming bulb. At the dealers suggestion he replaced the fuel tank fitting with one with an anti-siphon valve. Now the engine, a 200 Merc, sucks the primer bulb flat, doesn't make rpm, runs hot. Pull the line off the anti-siphon valve and the flattened out priming bulb returns to normal. There doesn't seem to be very much restriction from the siphon valve, but it's enough. Is this a common problem? Thanks

 

[rickdb1boat]

Re: Anti-Siphon Valve Problem?

I don't know how common it is, but it does come up fairly often here. I'd do away with it....

 

[Stumedic]

Re: Anti-Siphon Valve Problem?

I don't know how common it is, but it does come up fairly often here. I'd do away with it....

Thanks Rick, That was my suggestion. Just looking for a second opinion. Thanks.

 

[jimmbo]

Re: Anti-Siphon Valve Problem?

It kept my I/O from running on the first launching. There are electric soliniod types that might be less prone to trouble.

 

[Stumedic]

Re: Anti-Siphon Valve Problem?

At first, he bought another valve thinking the valve was bad, but a new one acted the same. If you suck through the fitting it really feels restricted, and I can understand why the bulb flattens out. I thought maybe outboards and inboards used a different valve? Anyway, I think a manual shut off valve at the tank may may it coast guard compliant. Thanks again. Stu

 

[Caddy_Kid]

Re: Anti-Siphon Valve Problem?

Same thing happened when I put a tank I pulled from an old I/O into a Tollycraft with a 100 hp Johnson. Didnt run for crap. Took awhile to figure it out, but finaly took the tank fitting apart and found the one way valve in there. They really hid it, but after removing that it ran, well, as good as a v-4 Johnson does!d