Removing frozen anti siphon valve.

[rfav21]

I've been having trouble with my fuel delivery. The problem is while running 1/2 to full throttle my primer bulb goes flat and can't be pumped back up. What I do to get the primer hard is release the drain valve on my fuel/water separator and I'm the able to run for a little while. So far I've changed the primer bulb, fuel/water separator, some of the fuel line. I've also tried loosening my gas fill cap and blew air through my vent line. I'm now at the anti siphon valve but it's really corroded, any ideas how to free this up, I'm worried about stressing the tank. Also what about removing the 90 degree fitting going into the tank? Is this fitting threaded normally?

 

[ezeke]

Re: Removing frozen anti siphon valve.

The anti-siphon valve is usually just a spring and ball bearing. You can knock it out. If you have part of the fuel supply system below the fuel tank, replace it later with an up-to-date anti-siphon valve.

Look at the vent outside the boat and be sure that it is not corroded; I once saw a boater replace the whole 50 gallon tank only to find that the vent had corroded shut.

 

[rfav21]

Re: Removing frozen anti siphon valve.

When I tested the vent on the side of the boat I disconnected the vent at the fuel tank and was able to blow air through the line and out of the vent. As far as the anti siphon valve it is mounted on the top of my fuel tank coming out of what looks to be a brass 90 degree connector. But since the anti siphon is aluminum I guess there is corrosion from age and since the metals are dissimilar. My concern is damaging the tank trying to crack the anti siphon valve loose from the brass connector. I'm also wondering if the brass 90 degree connector is threaded into the tank, maybe I can just change both fittings?

 

[Chris1956]

Re: Removing frozen anti siphon valve.

Normally the tanks have normal pipe theads. The brass fitting should unscrew normally. The A-S valve is usually easy to remove with a nail and hammer, after the fitting is removed.

 

[mikesea]

Re: Removing frozen anti siphon valve.

I have found it easier to remove the valve.What happens often is the disimliar metals,often brass and alum.have a reaction with each other causing corrosion.If you replace fitting,use alum if you can get it,.otherwise use teflon tape to cover the threads to prevent future trouble

 

[rfav21]

Re: Removing frozen anti siphon valve.

I'll try and remove the valve again over the weekend, if I can't get the anti siphon valve off, I'll try removing the brass fitting.

 

[rfav21]

Re: Removing frozen anti siphon valve.

I finally got the anti siphon valve off. The valve was sticking and hard to blow through. After removing the valve we gave the boat a good run with no problems at all. Thanks to all.

 

[snookhunter72]

Re: Removing frozen anti siphon valve.

I know this is an old post- but i am having the same problem - hoe exactly did you get the a-s valve off? I have a fear of me blowing a hole in the top of my tank?

Thanks in advance

Chris

 

[metriccrescentwrench]

Re: Removing frozen anti siphon valve.

It would probably be better to start a new thread than to ask a question by replying to a 2 year old thread - the thread police will probably be along soon and lock you up (or at least this thread).

The anti-siphon valve is probably screwd into a 90 degree elbow, which itself is probably screwed into the top of the fuel pickup. If it were me I'd just grab a wrench and go for it. Worst that can happen is you'll end up replacing the fuel pickup and elbow. I kind of did the same thing with a 30 year old tank from my boat while I was restoring it. I wound up having to get the fuel pickup out with an e-z out, wasn't too big of a deal.

 

[snookhunter72]

Re: Removing frozen anti siphon valve.

Thanks for the response. I just didn't want to rehash the same ol topic. I am going to try on saturday. I am afraid of breaking something on the tank. thanks for the help I will give it a shot.