[drifter]

Anyone know what anti-siphon valve the 8.1 Crusaders use?  It looks crowded there with the shut off valve under the round access hatch.

[Uhehner]

I recall the Crusader Service manual specifying 3/8" fuel lines and it would make sense to continue with 3/8" pipe thread. I will try and find the exact wording in the Installation Section. Also I would mate brass to brass or aluminum to aluminum to avoid any galvanic action.  Capt. George

[drifter]

Thanks for the reply.  I do not see anything on the tank under the access hatch that looks anything like the units when I do a search.  There is a shut off valve on the top of the tank, is that normal?  My owner's manual shows this valve on the bulkhead behind the engines where the fuel lines come out.  I can attach a photo later if that would help.
Dick

[Uhehner]

Normally there would be 4 valves. One for each of the fuel lines going to each main engine, one for the generator fuel line and a crossover valve so that both engines can be run off of one tank in the event you have a problem with the other tank. Capt. George

[drifter]

Capt.'
      On this vessel there is no cross over.  Shut off for each engine and the generator only.  The fine print at the bottom of this diagram in my owner's manual states 'no crossover on EFI engines' and indeed there is none!  But there is a shut off on each engine at the tank top. 
      I do believe I've located the check valve.  See photo.

[Uhehner]

I don't see an anti-siphon valve. I see a 1/4 turn valve with a pipe to flare fitting adapter and a flare fitting to hose barb fitting. Don't use me as the final word. Perhaps the 90 deg. fitting into the tank is an anti-siphon valve I'm not familiar with. Do you have fuel return lines to the tank on your 8.1's? Mine are the early ones with a single fuel line and a return that goes back to the fuel cooler.  Capt. George

[drifter]

Capt,
    You are quite right, however the fitting you describe matches exactly a check valve I found on line, same size, same threads.  I'm ordering one to see if it is the same.  I did see a 90 degree valve on line but can not find one for sale.
    Yes, I do have the return line.  This has been confusing since it is at best an unusual valve and this configuration is not as it left the factory according to Tiara, so it's by guess and by golly as they say.  
    I'm trying to chase down fuel flow as I feel it is the most likely cause of the alarm.  Just got the fuel pressure gauge.  I'll check that this weekend.  Getting a mechanic right now is folly.
Thanks again for your help,
Dick