anti-siphon valve foibles

[larryeddington]

Okay my engines start to die after running about 2 minutes under full throttle.

Freshly cleaned and kitted Quadrajet carbies, new fuel pumps, filters should be good, however they are the small frams that Trojan used. My take is it most likely is the anti-siphon valves. I have TEMPORARILY replaced the valves with a straight through fitting. Engines are Crusader 270s in a 84 Tri-cab that uses single 220 gallon fuel tank, so both pickups come from same tank and it is occurring on both engines not at the same time but one a short while after the other.

I have not tested it without the AS valves yet and will get back with result of a sea trial.

The valves Trojan used are 3/8 inch NPT on each end and are held in assembly by circlips. They seem serviceable and I will disassemble them and thoroughly go through them. Now for the big question;

WHERE CAN ONE PURCHASE THIS SPACIFIC VALVE, all I find out there are barbed ones which won't work as my, our, fuel lines are copper?

[gitchisum]

I'm not sure this is the exact one Larry

http://www.boatersplus.com/evm-inc.-evm ... aQoduKkHsQ

[Christian]

Hi Larryeddington,

I was looking into replacing my fuel valves as well. I have found that Anderson Brass Company has a good selection of marine fuel valves. their M670 series shutoff valves are UL Approved for Marine usage.

These are the ones I am going to use. I should be ordering them in a few weeks...

Try this link:
http://www.andersonbrass.com/MARINE_FUEL.PHP

I hope this is what you are looking for...

Cheers,

Christian

[larryeddington]

Thanks guys however the AS valve indicated is a 1/4 inch thread. Mine (ours) are 3/8 NPT on both ends so this will not work and I had found it also. Seems all the others have a hose barb on one end which will not work either.

My manual valves are fine so will not be needing them, it is the Anti-Siphon Valve I would like to replace.

The Trojan ones are off and on my work bench. They appear to be manufactured so to be serviceable. One end had a circlip that can be taken out and disassembly conducted. I think an overnight stay in carb cleaner and check for any foreign material to cause it not to work. They seem to open but by mouth you can barely get air through them with all the lung air pressure I can generate.

Thanks and will follow-up with the solution when found.

Larry

[g36]

when i had my f32 i replaced them and purchased from carver parts BRETT 920-822-7227. cant find the part number right now. belos is a pic. the flare adaptors are on each end of the valve. carver didnt charge bad for them that i can remember i dont recall finding anywhere else for an option but the price wasnt that bad from them.

http://www.marineengine.com/boat-forum/ ... 13&thumb=1

and here is a link i was involved in a few years ago on the trojan board with more pics or at least closer etc
http://www.trojanboats.net/wforum/viewt ... f=1&t=8528

[larryeddington]

Thanks g36 those look just like my Trojans' it is the section in the middle, actually there are three parts in picture. Ell, ASV and the flare adapter. the ASV had 3/8 NPT treads.

I will try and call him and see.

[larryeddington]

Another question regarding fuel flows.

On my 84 Tri-cabin I have one 220 gallon fuel tank. It has three fuel pickup tubes. One to each engine and one to the genny. My question is what is at the end of these pickups. In auto world with submerged pumps there is a sock or filter on the end of it is there something like that in our boats?

[The Dog House]

Another question regarding fuel flows.

On my 84 Tri-cabin I have one 220 gallon fuel tank. It has three fuel pickup tubes. One to each engine and one to the genny. My question is what is at the end of these pickups. In auto world with submerged pumps there is a sock or filter on the end of it is there something like that in our boats?

I can't say with regard to my Trojan but the Four Winns I had before the Trojan did not have anything at the end of the fuel pickup tube. The tube was just bevel cut and left open.

[Stripermann2]

Be sure to check the fuel filter at the rear of the engines too, they are inside of the metal canister. Often overlooked, this is the filter between the pump and the carb inlet filter. I change mine several times a year...

[larryeddington]

Thanks Striperman,

Mine are Crusader 270s and have only the inlet filter between the pump and carbie. My F28 has Chrysler 318 which have the metal canister filter between the pump and the inlet filter on the Carter AFB's.

[larryeddington]

Hooray I found our exact anti-siphon valves, they are just called check valves. Everything you want to know about them is at "circle-seal.com" they are available though you would have to go through a local supplier.

After cleaning mine carb cleaner could see the brand Circle Seal Model number is 2232B -3mm, I am going to call them and check what is the best o-ring to use in the valve. Then I will order 2 new ones. My old ones cleaned up really good, but want new ones that can stand alcohol gas.


Bottom line we now have a source for double threaded ASVs.

[larryeddington]

here is another source Goodyear

http://www.goodyearrubberproducts.com/2 ... ge0162.pdf

[gitchisum]

Thanks for posting the link!!!!

[larryeddington]

Here is an exploded picture of the Circle Seal Anti-siphon valve most of us have. According to the model number the o-ring is of Viton Rubber. My research indicates that BUNA-N rubber o-ring is basically the same and gasoline/alcohol does not effect it.

[larryeddington]

I ran the Phoenix II WOT for about 1/2 hour yesterday and she did not puke and die so I am left with that the ASV was causing the starvation of fuel. Have ordered 2 new exact replacements for original that Trojan used (Circle Seal) when here will install them taking out the temporary bypass. Solved I hope>