New Pump, No Power

[galakinokis]

My 93 truck started acting up and running rough. Took off the pump and found another used nice looking pump.
Fixed the KDP while the case was off so I know that the gears are set to stock setting and not one off.
My new problem is that the pump idles great, BUT anything past 1/3 throttle is nothing. Loads up a little, but just wont rev much past 1/3....
I indexed the throttle at 4:2, so i know that is ok. Also put in a denny 2 pin and still nothing... Smoke screw is not messed with. and power screw has about 1/2" of thread showing.

Just cant get it to rev, real sluggish. Im wondering if the guy had given me a non-ic pump instead of an ic pump? or ?

[galakinokis]

also have the pump set about an 1/2" from the engine head. Let it idle for about 45 min to warm up and get alot of fuel moving through the pump- disconnected the ksb and the engine died... Timing?? any way to move it without having to jump a tooth??

[skilletky]

are you sure that the pump gear did not move when you had the pump off? did you make sure the pump shaft keyway was on the shaft of the new pump and did you torque down the gear nut to specs?

[galakinokis]

Ive tried to retrace my steps and the only thing i can think of is that i did rotate the pump while it was unlocked and out of the truck to the tdc position so it would slide in at tdc, then locked it in the truck at tdc... I know that all the gears line up and the case is good!

[Mark Nixon]

Your original problem may not even have been injection pump related, but rather supply-side related.
Limited fuel supply, or aerated fuel makes these things do some really silly crap, sometimes.
IMO, the stock lift pump on a 1stgen is just this side of garbage.

BTW, if you had the wrong injection pump, I/Ced vs. Non-I/Ced, you'd know it, the lines wouldn't have been easy to put on, since the line adapters are different lengths.

You DO know that the KSB is on the SIDE of the pump, not up by the injection lines, right?

Mark.

[galakinokis]

Yes ksb is on the side, after warming up i can see a drip off the brass bolt on the ksb every 10 sec or so now... ez fix w/ an o ring.
I had bought the truck with a new lift pump installed... and new fuel within the last 2 months...
tried the ol' unscrew the gascap trick and still the same garbage going on... i can only get it started now with a shot of starting fluid, and will idle fine. I opened up the air boot in case it ran away and shot a bit of fluid into the turbo and it woke up immediately, so i know its starving somewhere.

[Mark Nixon]

New lift pump doesn't say much, with the quality of the crap we're being fed from Chin-A.
You have your symptoms, increasingly hard starting, will idle but not accelerate.

See if there are air leaks and/or swap in a new lift pump.

Want another test to do?
Plumb a temporary tank directly to the injection pump inlet (gravity feed it directly), then see how she starts, dollars to doughnuts the difference will be nearly instantaneous.

Mark.

[galakinokis]

Ok, thanks Mark. I will whip up a "new" tank and see how she goes.
Im still considering that I messed up the pump timing by rotating the pump shaft when it was on the bench... II unlocked it and was hard to turn, and ended up cranking it w a wrench to the tdc setting (around the 6oclock)

BTW the old pump had broken springs and a broken head/rotor, needless to say i cut my losses and just found another used one. BUT still have the other for "parts"

[Mark Nixon]

If you never took the pump apart, you didn't mess up the timing on the pump, it's pretty much foolproof.
The easiest way to goof on timing and have it still RUN, is if you inadvertently got the timing gear lined up wrong, say a tooth or 2 off.

Mark.

[bmoeller]

I agree with Mark. Think he's on the right track.

Saying you had the timing cover off, with the gear off, the timing could be off a tooth or 2. With the gear installed properly and key stock in place, the pump would have to be off 180*. Since it does run, I doubt that is the issue.

If the lines still have the quick disconnect fittings on them (both ends- pump and tank), you very well could have air in the system. Also, the fittings on the return line at the drivers side rear of the head can work loose and leak fuel and let air in when it is shut off. Just a square o-ring in those. Can snug them up a bit first, before replacing the o-rings. Make sure to use a 2nd wrench to keep from bending the lines. Nothing to hold them tight. Bend easy.

[RCCUMMINS89]

Pump dies when power to ksb is taken off.....

This tells me timing. It is impossible to get the timing off unless the gear itself has been skipped a tooth in either direction, the keyway is sheared at the shaft, or the timing marks don't line up. (if timing marks are off it will still run.)

[cmann250]

I believe the OP got it figured out. He said it runs good

[galakinokis]

Oh yeah, i finally figured it out yall. I had the wires mixed up at the ksb and fss!! I was at the end of the rope and then figured what the heck might as well see if they were wrong and that saved me a couple hundred dollars. Anyway now I have to find out why it keeps running after I turn off the key... just barely running (like 300 rpms?) But I just slowly put it in gear and its off.

[PToombs]

FSS is chipped would be my guess. Mine did it that way. Now it still does with my modified one, after I run it hard.

[Mark Nixon]

...I had the wires mixed up at the ksb and fss...

I'd have to say that's the first time I have seen or heard of this happening, but WTH, crap happens.

At least it wasn't major.

Mark.