Priming IP before install

Kevin 007

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Is it safe to remove the return fitting on the top cover of the pump in order to prime a dry pump with "clean" fuel/additive prior to installation and initial start up? To speed up the bleeding process and eliminate spinning the pump dry. I have replaced many of these pumps but have never filled one first; not sure why:rolleyes:
 

riotwarrior

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Kevin..Look where the feed line is...into the center of the metering block...feeds UP into the pump as such I'm not sure it would make a big difference...maybe it could help...electric lift pumps seem to be the primer helper more than anything...IMHO.
 

Kevin 007

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From my understanding, the fuel inlet in the center of the metering block won't allow a guy to just pour fuel through it (as the opening is far too small, it would take all day to fill the pump) unless that entire inlet is removed from the pump perhaps?? This is what im curious about, to clarify my original question; will anything pop out at me like springs or whatever, if I remove either this inlet or the return fitting at the top of the pump.
 

Ugly Moosling

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Filling the pump through the return is not necessary and won't help you prime the system. The area you would be filling is all return fuel and it's main purpose is to lube the moving parts and keep things cool, as well as create some case pressure to allow the advance to work properly. These pumps will run with the governor (top) cover and timing (side) cover removed and the pump basically empty of fuel. Once you ensure a good supply of fuel to the pump inlet it should only take a few tries to get the injection lines bled out and fire up. I would recommend filling the filter with clean additive or fuel through the smaller outer ring of holes, then crank til you have fuel at the pump inlet, tighten that line and crank til you have fuel coming out the injection lines at the injector. Snug them up, cycle the glow plugs, and you should soon be running. Just remember to crank in short bursts with starter cool down time in between.
 

jaluhn83

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Bottom line: Not needed.

Just pouring fuel into the return line woln't do much because of the backpressure valve and the fact that there's no way for air to get out.

I **strongly** disrecommend removing the top of the pump unless you absolutely need to. It's easy to put it back on wrong and turn the engine into a runaway. The shutoff solenoid has an arm the extents down that fits into a notch in the pump linkage - if you don't put it on gently from the rear and slide forward that arm will jam the fuel control in the full fuel position and short circuit the shutdown. Doesn't mean you can't do it, but I certainly wouldn't.

Also you're potentially putting dirty fuel into the pump. If you prime it via the system it'll only get filtered fuel. In fact as I recall there's a note to this effect in one of my service books cautioning against any sort of priming.

Most of the time it takes to prime is actually getting the injection lines purged - the pump itself fills pretty rapidly.
 

OLDBULL8

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You should NOT try and fill the IP at the return line on the top, when you remove the 90* fitting, there is a check valve under it, if you try to take that out, it may get ruined.
 

JSVD

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they prime really easily with a bulb. just hook one up pre filter and pump it.. bleed your filter then put something under all the cracked injectors. Stop when they're a tad wet. May take cranking it once.. if you want to save your glowplugs use a wire to the starter and the IP. Make sure the car is in neutral.
 

icanfixall

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The idea of pre filling the pump before cranking is sound but really not necessary at all. Way too many things from dirt getting in to a runaway engine if the top cover is installed wrong. Send the fuel thru the filter so you know its been filtered and you will have a happy pump for a long time.. Prefill the new filter with atf to help the new pump is about the most I would do but.. Make sure the atf in poured only thru the small ring of outer holes in the fuel filter top. Pouring directly into the large hole is allowing unfilter fuel to enter the new pump. Even a new can of atf is going to have dirt in it that will ruin a new pump. You can't see it but its there non the less. Pour slow and do it safely. No reason to try and plug the center hole with anything. But if your CLEAN thumb works then use it. There is a reason that plastic bag is on the new filters. You never see a plastic bag on an oil filter do you.
 

Kevin 007

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You never see a plastic bag on an oil filter do you.[/QUOTE]
The Baldwin oil filters for our trucks come wrapped in plastic.

Yeah ok, I will refrain from priming IP's, however the idea of a bulb pre filter is a neat idea.
 

icanfixall

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Three words... ELECTRIC FUEL PUMP.

No truer words were ever spoken Mel. For those that CHOOSE to continue to use the mechanical pumps will always amaze me. The electric is a simple upgrade that has no down side to it. It saves the batteries. It saves the starters. It purges the air faster. the engines start faster because of all the above. I respect members to make choices but still wonder too..
 

Kevin 007

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Yes, I also respect the choices that any gear head will make. Im not intending to start a mechanical vs electric debate but after having two electrics fail on me on different rigs and a third that had the electrical connectors corrode on a girlfriends truck when she was many hours away from home with a horse in tow, all in a time when I was needing to get somewhere quick and a parts outfit was nowhere near by-cuss; electric pumps sure left a bitter taste with me. No, I no longer remember what brand pumps they were. And it makes me wonder why put an electric pump on a truck that is desirable for being able to run on nearly no voltage draw. Im not saying the mechanical pumps don't fail as we all know they do, especially this new made in China crap that is out there; but "for me" the mechanicals have been reliable. Knock on wood. I would like to have a bypass around the mechanical pump with an electric for priming but, don't have that rigged up yet.

Yes a guy could have a spare electric pump under the seat to swap out a bad one in a pinch.... but I didn't have the money to spend at the time.

I appologize for straying from my original question on an electric rant.
 
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bbjordan

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Optimus Prime

I prime my IPs now. The top comes off and gets filled with clean diesel. I've read about putting the top on incorrectly, but I've tried to put it on incorrectly, but couldn't. At least without having to force it. I then hook up the input fuel line to the pump and fill it while rotating the pump input shaft clockwise. Fill, turn, fill turn...I can feel the pump filling up and getting harder to turn. With the top off you can even see air bubbles coming out where the vent wire is. Pretty soon it is spitting fuel out the injector ports. Disconnect input fuel line. Install IP. Reconnect input fuel line at IP end. Fill line. Loosen filter head bolts. Connect line to filter head. Tighten filter head bolts.

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I can usually get the injector lines bled and engine started by 3 cranking sessions.

I agree with Mel tho; electric fuel pump is the way to go. That's one of the upgrades on my list.
 

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