82 300sd air in line coming from tank?

[greg240d]

Hi guys my driveway is on a include I'm getting air in my line from the tank I removed the tank replaced the strainer and fuel lines still air in line and hard starting in the morning lm at a loss . i disconect the lines from the pump and small air bubbles are coming from the back line .where could the air come from? Thanks for your help. Greg

[sixto]

Where do you see air? I take it this doesn't happen when you park nose down. Does it happen with the fuel filler cap removed?

Sixto
83 300SD

[greg240d]

Hi thanks for the help this is a new one for me I've been working with these diesels for 5 yrs I don't understand this one. The answers to your questions The tank lines are not connected to the pump and small bubbles are coming from the tank . don't know I just backed the rear end up on ramps to see and fuel cap has been off the entire time. Can a clogged vent line be the problem? Thanks Greg

[Millennial]

I would check the lines going to and from the tank for any kind of holes, shredded, etc. I would also drain the tank, pressurize it and make sure there isn't a pinhole somewhere. Only so many causes of said issue. You can clear out the vent line to see if that would help it, maybe it has negative pressure. Are you hearing any sort of hissing when the cap has been left off for a long time?

[greg240d]

Happy new years to everyone thanks for the help. Last night I put the rear end up on ramps
Still air in line I thought it would be OK but the same problem I'm going to make sure its the tank and lines and remove the tank.
Thanks Greg

[SD Blue]

If you have the cap off, I thinking it wouldn't be the vent. I'm wondering if there is a major crimp in the line, somewhere under the car, causing a restriction.

[greg240d]

I found out the vent line check valve not working l can blow through it both ways do you think this is the problem?? Small hoses are also bad. Thanks Greg