Well this one has me stumped.
I have three N/A Injection Pumps that I am trying to clean up to sell. I got one fired up right away by using a jar and two hoses and a drill to spin it round and round.
One pump is toast! I don't have any idea why the inside of it looks like it does because I bought it for cheap on Craigslist. Wasted my dime there. It is reddish, flaky, bubbly stuff that does not even wipe off with diesel. So that one is not going to get any more love from me.
The last pump is the one that is making me write here. I was able to spin it up and get fuel out the top of the OUT bolt and return to the jar. Granted it had lots of little bubbles in it but I expected that. The one working pump did as well. I removed the delivery valves off the back of the pump and verified they were stuck shut so I freed them up and tried again. Nothing, not a drip not a squirt. I removed one of the valve bodies altogether and it spits out like no tomorrow.
So what might cause the pressure internally to be so low that the valves are not opening to let it out?
Is the pump not cycling back and forth enough? I verified that the collar and throttle mechanism is all in place as it should be. Actually did that three different times for different thoughts on the matter.
Might the pump be plugged? Hmm, didn't check that, but with the delivery of fuel out the back without the valve in place I think at least one hole is working correctly. Maybe I need to pull them all off and see.
What are your thoughts on this matter? Where would the restriction be? Where would I be losing pressure?
Let me know, I have spent a couple of afternoons soaked in diesel now and still have no solution. So looking for ideas I have not tried.
Later, thanks.
You turned the engine over with the top off and everything is moving right inside?
I mean turned the drill and shaft?
I kept the top on the pump because I think it needs to build pressure inside of it to work. Correct or not correct?
I have to have some way to get the excess fuel out of the pump and back into the container. So a hose on the OUT bolt is doing that.
I have the IP snug in a vise in the shed and I turn it with a drill but maybe my drill is not fast enough to throw those little vanes out to the edge on this one pump. The amount of fuel returned to the container is less than the other working pump I was doing the same way.
I don't know if the internal pressure has to be higher than it is in order to get the amount of squirt out the back to be enough to push those delivery valves open. I think that is where my problem is. I might pull a couple of them off and put them on the other working pump and see what happens. If all four work then I will have to suspect a weak pump on the high pressure side. Something I have never experienced before.
I have time tomorrow to fiddle with it some so maybe I will do that. It is raining outside anyway and I can't do anything with the struts I put on that are now too low to let the wheels rotate without rubbing on anything more than a short pothole or bump.
Always something with these trucks.
I was thinking just a few turns with the top off to make sure the shaft is turning and moving right.
You know the collar is in the right place, you already checked that
but not with parts moving.
Ahh, I did put the pulley on and turned it round and round a few times to watch down in from the top to see if the collar was hooked up and if the cam was moving in and out. So yeah, I did that!
I was thinking you were asking me to run it open top when spinning it with the drill. That would be a disaster. But a few turns by hand, yep, works like I think it should, but it doesn't.
I spent the day working on the struts today, I will fart with the pump tomorrow.