thought it was bad lift pump

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thought it was bad lift pump

Postby 2uphill » Fri Sep 25, 2015 1:35 am

Well, my truck quit the other day. I was going up a hill to the house and when I leveled out it just quit. ...Had a 1/4 tank of fuel, I thought maybe lift pump. Being the mechanic that I'm NOT, I walked to the house dialed up 1st gen.org and tried to find some G&D. Went back cracked the banjo bolt on the filter and primed the pump till I got fuel...then cracked injector line and couldn't get any fuel up to it even after bout 30-40 strocks. I remember reading a funny (at the time) quote from a member saying it only takes bout 137 strokes... also when I worked the priming lever it felt 'limp' like not pushing fuel...so I Hit he ign switch couple times for all six cylinders till some fuel showed at alll six inj...the engine fired right up..." air in lines'...but I also saw air coming (bubbling?) out of top of 4 of the injectors where the wet fuel from bleeding lines...I tightened the injct nuts at least as tight as they were to get loose and the air was coming off the top of injector not the nut... Soooo what might this be...(if I explained well enough)..I still think I may have a week pump as well, as the priming lever not having much resistance.
90 d350, SRW, 2wd, 727, stock, except banks i/c, 85K
84 w350 crew cab, I/c 89, s300, 727, 4x4, 130K
90 w350cc, 3.54, getrag, 125K
82 d350 crew cab project
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2uphill
fuel screw!!!!
 
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Re: thought it was bad lift pump

Postby dazedandconfused » Fri Sep 25, 2015 3:44 am

It sounds like you weren't on the tall portion of the cam lobe when priming the lift pump. The fuel bubbling out of the injectors is fuel leaking around the sealing copper washers it sounds. The easiest way to get one running I've found is to prime fuel to the injection pump then break the first three injetoe lines loose and crank the engine. It's easier with a extra set of hands. I crank until it stumble then snug up two of the lines just leaving one loose and it will usually fire off. Then I just tighten everything up and let it idle.
Big Andy
1983 Dodge D150 that has been repowered with a 93 Cummins/518 running gear AKA The Ugly Duck! I would much rather build them then buy them.[
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Re: thought it was bad lift pump

Postby 2uphill » Fri Sep 25, 2015 6:19 am

Will certainly remember that...thks ... :)
90 d350, SRW, 2wd, 727, stock, except banks i/c, 85K
84 w350 crew cab, I/c 89, s300, 727, 4x4, 130K
90 w350cc, 3.54, getrag, 125K
82 d350 crew cab project
User avatar
2uphill
fuel screw!!!!
 
Posts: 72
Joined: Thu Aug 27, 2015 11:18 am
Location: Front range
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Re: thought it was bad lift pump

Postby dazedandconfused » Fri Sep 25, 2015 12:24 pm

No problem. Depending on miles on injectors it may be a good time to upgrade or have yours checked out since you will probably have to pull them to replace the coppers so they stop leaking. Some people have been able to snug them down and they stop leaking but I've never been that luckym
Big Andy
1983 Dodge D150 that has been repowered with a 93 Cummins/518 running gear AKA The Ugly Duck! I would much rather build them then buy them.[
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dazedandconfused
14mm rotor
 
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Re: thought it was bad lift pump

Postby PToombs » Fri Sep 25, 2015 5:14 pm

When you build up pressure with the lift pump handle the pressure pulls the diaphragm up so it doesn't pump any more. If you wait a few minutes then the pressure bleeds off and you can pump it again a few strokes before it "goes away" again.
I usually just open 5 or 6 injectors all at once and spin it until I get fuel, then tighten the nuts and fire it up.
pete

Just enough power to break everything behind the crankshaft.
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PToombs
14mm rotor
 
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Re: thought it was bad lift pump

Postby 2uphill » Sat Sep 26, 2015 8:28 pm

Thanks for the additional suggestions, it's nice to hear the variious approaches. that work ;) .. thanks guys
90 d350, SRW, 2wd, 727, stock, except banks i/c, 85K
84 w350 crew cab, I/c 89, s300, 727, 4x4, 130K
90 w350cc, 3.54, getrag, 125K
82 d350 crew cab project
User avatar
2uphill
fuel screw!!!!
 
Posts: 72
Joined: Thu Aug 27, 2015 11:18 am
Location: Front range
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