jd 40 carb. question

[valley iron]

rebuilt carb on my jd 40. it has a marvel tsx 530. runs for about a minute then dies like it is running out of gas. put in complete overhaul kit and made sure all passages were clear. new inlet screen going into carb,new sediment bowl and getting plenty of fuel.adjusted idle adjustment and load screw to initial specs,even bent float tabs from suggested spec to less and more. only issue I noticed is when took off gas cap there was suction on tank like not venting properly,but starter clunked out before I could try it with gas cap off.having starter rebuilt and will try when I get it back.if that dosent work any suggestions?

 

[old]

A vacuum build up in a gas tank will in fact stave the carb of fuel and have what your having happen. Sort of like if you put a soda straw in a drink and put your finger over the end the soda will not drain out because of the vacuum that is made

 

[valley iron]

yes I only noticed tank having a vaccum before starter quite so I couldn't check my theory but hopefully that will be my problem