Question about lift pump hand primer

[Phil Stuart]

I Changed the fuel/water separator filter yesterday evening on the old girl.

Cleaned everything (WIF probes) and new gaskets. The change went well until I got the filter back on,cracked the bleeder screw and commenced to pushing on the hand primer lever.

Now I did not have any clean diesel fuel on hand so I just put it all back together and thought the hand primer would fill up the filter with minimal priming and fuel would spit out the bleed port.



This did not happen. I must have pushed the lever for a good 2-3 mins, nothing came out. I opened the drain valve on the filter and nothing there either.

I had to disconnect the wire to the shutdown solenoid and had the wife crank the engine while I checked for fuel at the bleed port. It took two tries and WHOAAA out comes the fuel.

closed the bleeder and hooked the wire back to the solenoid and she fired right up no problems and without sputtering at all.



Does this mean the hand priming function on the lift pump has bit the dust or what?I didn't think there was any special way to bleed the system. The pump works fine with the engine running.



Any clues folks?

TIA,

Phil

 

[JLEONARD]

The pump works off of a cam lobe. If if the pump's internal lever is on the peak of the lobe , the priming lever won't work. In this case you would need to "bump" the engine over a few degrees to get it off the top of the lobe and try again.

Jay

 

[Phil Stuart]

Jay,



That would make sense to me. I never really gave it that much thought Nextime I'll remember that.

What are the odds of having the lift arm stop right on top of the lobe of the cam



Thanks again,



Phil

 

[Mel Fuelling]

Phil,

The odds are about 100-1 that it just happened to you. I've had

it happen about 1 out of 20 tries on my pickup. My experience has been: Keep this possibility in mind, it will probably happen

again.



Good luck,

Mel

 

[Greenleaf]

Prime Time

I keep filtered fuel on hand just for this. Fill my fuel filters to the very top then screw 'em on. No priming required. BTW if you were to change out the primary on a 5. 9 in a Bluebird bus and not fill it first, well, you wouldn't be driving it.



Just my experience



Scott

 

[dpuckett]

Phil,



The lift pump lever seems to stick on the cam lobe on me every other time I try to prime it by hand. I think some levers are better primers than others. I fill the filter with injector cleaner about 1/2 way, then prime it with the pump. The dose of cleaner cant hurt anything (at least if you have Stanadyne, Power Serivce, etc), and if the primer doesnt work for some reason, it will still run about 20 sec w/o fuel from the pump. (Found that out yesterday when I replaced batt cable on Mom's, removed the fuel line for easier access to the starter, forgot to repace it). THat gives it time for the lift pump to catch up to the demand of the injector pump. FOrtunately, if it runs out of fuel, or you get air in the system, they bleed out easily enough. Normally only have to crack 3-4 injectors, then it catches and runs, though rough for a little bit.

Daniel