Air in fuel line

[Chuck Gramling (WI)]

My kind-of-new-to-me 89 suburban has problems with air getting into the fuel line. Apparently it was a new problem which developed in the days before the seller delivered the car to me. Could it be related to the replacement of glow plugs which was just done in conjunction with an alternator problem?

Or the fuel lift pump I suppose ?

I thought I read on this forum once that worn injectors could introduce air ? Is that right and would it be related to the injectors themselves or are there o-rings or something that I might try replacing ?

(Vehicle has 150k on it).

Thanks,
Chuck

[britannic]

An air leak usually becomes obvious when your vehicle sits over night and the cooling fuel contracts in the tank and puts a vacuum on the fuel supply lines.

A quick way to check is to get a second "gas" cap and drill and install a tire valve. Then pressurize the tank between 5-10psi with compressed air and carefully inspect the lines for seeping fuel.

Look at the fuel filter first, also check the injector pump for leaks at the throttle shaft and at the advance actuator plunger (passenger side bottom of pump), then look at all of the fuel line connections.