little white yj 622 Posted August 20, 2010 Share Posted August 20, 2010 i have the AD 150 with a straw. i have been running 17 psi all the time.all the way to empty. just lately i noticed that now it drops pressure when comming to a hard stop at 1/4 tank of fuel. like to 5 or less just for a sec the right back up to 17psi. I did just put a needle valve on the line to the gauge, and it's open a little. can this valve be causing my problem? and is it ok to drop pressure for a sec or two? i going to open the valve full open untill i get fuel tomarrow. Link to comment Share on other sites More sharing options...
Owner Mopar1973Man Posted August 20, 2010 Owner Share Posted August 20, 2010 Nothing new... Everytime I lauch hard from a dead stop at 3/8 or less I see the same thing... Needle valve isn't the cause... It might be the fact with the heat and slooshing of the fuel it might build a bit of pressure in the tank swelling the tank slightly. Then increasing the gap on the draw straw... Just a guess... Link to comment Share on other sites More sharing options...
little white yj 622 Posted August 20, 2010 Author Share Posted August 20, 2010 Never thought of the heat thing. It's been hot here in Pa. and the AD was installed in OCT. last year. Link to comment Share on other sites More sharing options...
JOHNFAK Posted August 21, 2010 Share Posted August 21, 2010 Not sure - but you may be able to bump up the pressure at the low end and the hi end via the regulator spring. Page 25 (section9) of the link below http://www.injectorwarehouse.com/diesel/dodgecummins_diesel_airdog/install-manual-original-98-04.pdf See if bringing it up to 20 or so raises your low end when driving 1/4 full. Link to comment Share on other sites More sharing options...
jncornett Posted August 22, 2010 Share Posted August 22, 2010 My 05 did this at or below a 1/4 its the fuel moving to the front or rear of the tank... If you could hear your pump you could hear the change in pitch it makes as it loses and then gets a better supply of fluid at the draw straw after the momentum slows from stopping.. Link to comment Share on other sites More sharing options...
JOHNFAK Posted August 22, 2010 Share Posted August 22, 2010 My 05 did this at or below a 1/4 its the fuel moving to the front or rear of the tank... If you could hear your pump you could hear the change in pitch it makes as it loses and then gets a better supply of fluid at the draw straw after the momentum slows from stopping.. doh thats a good point. I was thinking the draw straw is pretty much usually at bootom of tank. But yeah with enough space and fuel moving. Then the extra pressure (spring) will be no use. Link to comment Share on other sites More sharing options...
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