Fuel Re-Prime Procedure

[tnlegendracer]

I can already tell the gauge isn't exact on reading the auxillary tank. In the event I run my '03 4x4 Dmax out of diesel, what is the procedure for repriming? It didn't come with a manual, but I can't find the bulb mentioned in other post and don't know where the bleed screw is.

[DmaxMaverick]

The filter housing is on the right (passenger) side of the engine bay, between the battery and engine. The priming pump is the 1.5" dia. "canister" looking thing on the top, and the bleeder is the black plastic screw inboard of that. The pump is operated by pushing it down and releasing it (spring loaded up).

Best bleeding procedure is to pump it up (slow, full strokes, not stabs) to significant resistance, then loosen the screw until the pressure is relieved, or fuel escapes. Repeat until you get fuel, then tighten the bleeder and pump up again a few times to prime the fuel pump. Be careful with the bleeder, it's plastic. Use a nut driver for best results, or at least a screwdriver large enough to prevent damage to the slot. Do not overtighten, the dealer will have to sell you an entire ass'y ($500

[LanduytG]

[quote] Do not overtighten, the dealer will have to sell you an entire ass'y ($500

[tnlegendracer]

In doing some searches, there's mention of cycling the pump/key on roughly a half dozen times with the bleeder open (I think). Does that come in to play at all here or will the little 1.5" pump gizmo do the trick?

Curious because I think I ran it out this morning coming down a hill at 70mph. No pedal response so real quick I switched over to the main tank and it came back on. It seems to be doing okay now, but knowing me (or my wife who's not familliar with the auxillary tank or its capacity) I'll run it out some time not paying attention.

[DmaxMaverick]

Originally posted by tnlegendracer:
In doing some searches, there's mention of cycling the pump/key on roughly a half dozen times with the bleeder open (I think). Does that come in to play at all here or will the little 1.5" pump gizmo do the trick? Cycling the key will do nothing to prime fuel. The Duramax (in stock form) has no electric fuel pump. You will have to prime it using the pump on the filter head. The procedure works on vehicles that have an electric fuel pump with a "start up" timed cycle, where the pump engages for a few seconds when the key is turned to run.

Your experience running downhill at high speed sounds reasonable. The engine stayed "in gear" on compression, allowing it to keep the engine spinning fast enough to "reprime" the fuel pump.

You could eliminate all of the above by installing an electric fuel pump. Kennedy should have a kit available soon, with all the electronics to make it "Duramax friendly".

[JohnnyR]

I embarassed to admit it, but I did run out of fuel once on my '03 Duramax. I can attest that all you have to do,after adding fuel in the tank, is to bleed the air at the fuel filter vent like when changing the filter. It started right up. Got to looking at the bleed mechanism, and I could see why. It's above the injectors or at the high point in the fuel line, on the LB 7 anyway. So you don't end up bleeding injectors to get it restarted.
Yet another reason to have a Duramax.