[single2coil]

Hello everyone, been enjoying our very early spring in Puget Sound. Went sailing today, well actually had the main up but very little wind, so we just drifted.

When time to head home, I noticed the raw water anti-siphon valve was leaking salt water. Yes, it is on the raw water exhaust elbow. Suddenly leaking, I do not understand. Hoses are tight. Sea water coming from top of anti- siphon valve. The raw water screen is clear. I don't like salt water leaking into the bilge.

Any ideas? Appreciate your input.
Thanks,
Roger L. (single2coil)

 

[single2coil]

need to add Yanmar 3GM30F engine with 1900 hours,

 

[PorFin]

Sounds like the air valve on your anti-siphon valve is stuck open. It happens sometimes. If you can, take the valve apart and clean it. Different valve designs have different internals, so that's about the best I can advise without additional data.

 

[Jaramaz]

Yes, take apart and clean is the first option. In salt water, the anti-siphon gets some salts and other things in the sensitive parts.
- actually, most anti-siphon leaks a little.

You may need to boil parts of it to get away with some of the salts. One can try chemicals - then very weak (lemon acid, or similar. Takes ages ...). But not mechanical as in screwdriver! Brush is good.

If this doesn't work as intended, then consider a new anti-siphon. Not sure which you have, but there are some new anti-siphon vents around which are much much better than those used 20 years ago.

The real long shot is of course to remove the anti-siphon vent totally. Replace with another vent which is easily fabricated - use a T-piece, make a small hole in it, attach a hose which is going either outboard or in the cockpit. Small amounts of water will tickle all the time the engine is on.
This is usually considered as a much safer construction. Until Med had his long thread about what could happen with such (he seems to have got some bugs living in the hose and ... then it doesn't work. His engine was toasted and so on - myself I am not toally convinced but that is what Med is saying).

Myself? Oh, I have about the same engine as you. No anti-siphon at all. Engine above sea leavel.

/J

 

[single2coil]

Forespar Vented Loop Forespar Vented Loop

Thanks Porofin & Jaramaz, appreciate the advice and will get started to fix or replace.

I have the Forespar Vented Loop , black plastic.

Is there a better one?
Thanks,
Roger L

 

[PorFin]

Thanks for the addl info.

The Forespar's pretty easy -- uncrew the top plastic cap and pull out the rubber duckbill valve. Clean, inspect & reinsert. If I'm not mistaken, the duckbill is available as a repair part.

"Better" is kind of tough to reach agreement on, since preferences vary. The most important thing is that it works.