603 Primer / Lift Pump Rebuild Kit?

[300TDT 1987]

Hi All,

My pre (plastic) fuel filter is only about half full at idle, you can actually see it draw air into the line that goes to the primer/lift pump. (I've disconnected the fuel heater for the time being).

The car will start and idle fine but I'm afraid to drive it for fear of stalling out when the IP gets a good does of air through it.

I attached a fuel canister directly to the pre filter, still only registered about half full with the direct method, eliminating any air leaks on the hard fuel lines to the tank.

I have replace the fuel lines to the lift pump, pre filter and hard line to tank. Have yet to replace the IP lines from the secondary fuel filter, but I don't see any diesel seepage.

I'm now assuming something is up with my lift pump.

Is there a rebuild kit or do I just take it apart and clean it and install a new gasket?

Any help is greatly appreciated.

Cheers