Vacuum diesel out of VE injection pump prior to sealing? De-prime the pump?

[Benjamis]

Is there a reason everyone lets diesel spill out of the pump when replacing seals? (particularly the head seal and QA and top cover seals)
Why not vacuum it out? Seems most people use their mityvac to prime the pump when they are done, why not use the mityvac to de-prime the pump so diesel doesn't spill everywhere? Or would that not work for some reason, which is why everyone opts to stuff rags and paper towels around it and then blast it with brake cleaner when they're done? Why? Would it blow up the pump?

 

[garciapiano]

There’s nothing stopping you from doing it. It’s just an extra step. Putting down some towels is ostensibly easier than pumping all the fuel out, and no matter how much you remove, you’ll still drip some in the process of removing the QA.

 

[ToddA1]

Unless you can get a tube to the bottom of the pump, which you can’t, how do you deprime? I guess you could possibly pressurize the pump and blow out the fuel. The pump doesn’t hold that much fuel... I’d wager 10oz or less.

I’m guessing you’re doing the head seal on the car? That head gets awfully wobbly...

-Todd

 

[Benjamis]

I did the QA seals today. The head seal is not leaking, so until it does, I will hold off, unless there comes a day when I am bored. The main leak was actually the center plug with the 24 mm triangle bolt. Luckily I have surplus 24 mm sockets around, and drilled out the triangle part on a drill press, fit nice and snug, and good thing, because I had to get out the breaker bar to get that thing off. The QA seal only had a slight leak but I opted not to mess with it at the time as it was 20 degrees out, mid winter, etc.

Needless to say, I already spilled the diesel all over rags once, and thought it would be nice to not do that again. I tried vacuuming the diesel out of the return line from the injectors after unhooking the supply line to the pump from the filter, but realized it was pulling fuel out of the return hose to the fuel filter, and maybe not at all from the pump, although there was noticeable suction at the supply inlet. In hindsight, I could have tried plugging the return line to the filter and seeing if it would suck the diesel out of the pump, but didn't think of it at the time and just wanted to get the job done and not mess anything up. I pulled about 5 ounces of diesel out til it was just pulling air, was hoping just to pull enough out to get the level below the QA, but my vacuum attempt did absolutely nothing to lower the level of diesel inside the pump, it was still filled to the brim, so I ended up spilling the diesel on rags again. Not a huge deal, just would rather not make a mess if I don't have to.

I suppose I was worried if pulling a vacuum on any of the lines could in any way damage internal parts. I wouldn't think so, but you never know, if you don't know.

Needless to say, she fired right up, and runs like a dream.