FIREDUDE

ok guys i got a 1989 dodge cummins 2wd here that belong to our local fire dept, here latly its getting hard to start once its set for acouple of days, its got 2 fuel filters, an glass filter along with the stock filter, in the glass filter you can see lots of air bubbles, what could this be??

G1625S

Most likely the factory steel lines from the tank are rusted and allowing air into the system. I'm replacing mine 2 feet at a time because I'm cheap and dumb I would recommend replacing the send and return lines with diesel rated rubber hose. I can't comment on this second fuel filter you speak of---got any pics?

FIREDUDE

its up by the intake , ill try and post some pics of the filter,if your still online now, cruise over to chat as i got more questions

Underpsi

a crack or hole in the line somewhere allowing air to get in

Underpsi

can the rubber line replace all the factory lines from the tank up to the lift pump and the return line as well?

G1625S

yup. only thing stopping me from finishing the job is that I'm lazy and it's cold out

Underpsi

lol ya, thats alot easier and cheaper then steal lines!

ihpower

mine as all rubber lines on it

Trebor

I would check all of the easy and simple stuff first; All of the hose clamps and hoses to the "glass filter" first, then the gasket inside of the glass filter and the retainer & gasket (if it has one) on that filter. Then I would check the hose between the frame and the lift pump, followed by the hose connections at the tank. My guess this truck sits inside and has about 100,000 miles or less? A bad or dirty check valve in the lift pump could also let the fuel drain back into the tank. The pump could cavitate air into the system while it pulls the fuel up from the tank. The additional fuel filter could be a hint of dirty fuel problems in the past.