Lift Pump Question

[NYChris]

Replacing my lift pump tonight. Have been having intermittent trouble with the truck stalling then acting like there's no fuel. The primer lever seems to be inoperable and the only way I can get it to go again is to pump the accelerator until my leg falls off. Acts like it loses its prime and the fuel drains back to the tank.



Anyway, the one that's coming off looks to be original with 175k so I figure why not. It will probably be a worthwhile $70.



Does anyone know the torque specs for the lift pump bolts? No manual yet, but it will definitely be the next $70 I spend!!!



Chris

 

[RGT]

18 ft/lbs. Your lift pump will be inoperable if the pump drive lever is up on the cam, try rotating engine a little and re-trying the lever... .

 

[NYChris]

Thanks for those specs RGT.



I have tried the primer after bumping the engine over and still nothing. Good advice though.



Should be fun working by the glow of a trouble light on my back in the driveway this evening. Oh to have a garage my truck would squeeze into.

 

[tugboatphil]

Chris,



Keep your eyes on EBay for a manual. You never know what will come up there. Even if you have to get a manual on CD, it would be a start.

 

[dpuckett]

Originally posted by NYChris

... and the only way I can get it to go again is to pump the accelerator until my leg falls off... .

OK, I realize you are a newbie to the TDR, so I'll go easy on ya When the engine is not running, there is no way to pump it up like an old carbureted engine. Read the sticky on the workings of the VE pump. It is easier for me to understand because I've been inside one or two. But the gist of it is, the plunger will only plunge when the engine is turning, either via running or the starter. Dont pump a diesel- it a waste of effort, not to mention wear on the throttle cable and shaft- rather, hold it to the floor until it starts, then let up when it runs. Clear as mud? \



FWIW- If all is well, you should never have to touch the pedal to start a Cummins Super B- the pump is set to flow max fuelling at crank RPM. THat is why there is the big puff of smoke at start up.



Daniel

 

[NYChris]

Daniel,



The part about pumping the pedal 'til my leg falls off was just a bit of humor... probably not very detectable though. Being a new guy I guess I do deserve a little ribbing. I would have to crank and crank and crank with the pedal on the floor before it would begin to fire. What a pain, and it would act up in the worst places when I didn't have time to screw with it.



The new lift pump is in now and seems to be working as it should. The primer pumps fuel noticeably so that's an improvement. The worst part of the whole job was scraping off the old gasket. I was at it for an hour or better.



Have another problem now though. Upon final inspection after the lift pump install, I noticed some fuel leakage around the top of the injector pump. Looks to be coming from the throttle shaft area. How critical is this? I know any leak is not good, but am I looking at a rebuild or just a seal that I can install myself?



I'll read up on posts regarding the VE and see if I can soothe my fears any.



:{ :{ :{

 

[cerberusiam]

You replaced the lift pump and got the supply pressure back where it is supposed to be now the you will find the bad seals in the injection pump. Kinda sounds like my luck, replace a piece and break three down the line.



There are 3 places on the injection pump you may have trouble with the increased pressure.



The throttle shaft, which you are seing now.



The o-ring on the fuel pin inside the aneroid housing.



The little oval plate on the back side of the pump next to the block.



The first 2 are relatively easy to fix. You can pop the top off the pump will it still on the truck and fix them yourself or have it done at a shop. The throttle shaft has an updated bushing and seal if the wear is enough to warrant. The aneroid seal is easy also. The third one will probably mean removing the pump to get to it. Not that big of deal if your handy with tools.



While the top is off the pump would be a good time for the 3200+ gov spring.

 

[dpuckett]

Keep an eye on the top of the pump for fuel leaks, and see how bad it is. It's your call on whether or not to get it fixed; it doesnt affect the high pressure pupming of the IP. Mine comes and goes, surprisingly enough. SOme weeks it leaks bad enough for me to almost buy the parts to fix it; then it will quit for a while. Weird, to say the least.

 

[NYChris]

Thanks guys. I'll keep an eye it and see if it gets better or worse. Looks like I should start shopping for some seals and maybe a spring. Any advice on where to go for these items?

 

[MMiller]

Pastor Bob had posted a question about throttle shaft leaks. I thinks they got something going on north of the border there. I wonder if they got some HI tech repair worth some bonus hp.



How bout ti pastor, still there?



Michael

 

[Greenleaf]

PDR has the updated throttle repair parts.



-S

 

[dpuckett]

Originally posted by MMiller

I thinks they got something going on north of the border there. I wonder if they got some HI tech repair worth some bonus hp.

Yeah, he's got us south of the border in on it, too, now . Not sure it'll be worth any bonus HP, though. Wont do anything for power, as far as I can tell. Should help longevity and integrity of the unit, though.



Daniel