Author Topic: Primed the IP but no fuel to inj. lines (Read 2721 times)

turbosyncrobus · « **on:** February 21, 2009, 11:54:29 am »

I'm on my second pump, both used, but I have primed the pump sufficiently. I have fuel to the pump, coming out of the return when cranking, but I'm getting no fuel coming out to the injector lines which I have removed to assist in troubleshooting this. I changed the pump because the first one was doing exactly the same thing that this one is doing. I even went so far as to remove the plunger from the Fuel Stop Soenoid even though it was working fine. Also, to ensure that I'm getting fuel supplied, I put a low pressure inline Bugpack fuel pump to supply fuel to the inlet. What am I missing, or what can I do.
Also, The first pump is the one that was on the engine when I got it, and by the looks of it, it had been sitting for many years. As I understand it hasn't been on the road in a few years. The other pump came off the eco-diesel engine that I pulled from the Pick-N-Pull a few months ago, and that one appears to have been run somewhat recently, and when I took the lines apart, plenty of fuel came out of them.

Thanks

jtanguay · « **Reply #1 on:** February 21, 2009, 12:05:19 pm »

Quote from: "turbosyncrobus"

I'm on my second pump, both used, but I have primed the pump sufficiently. I have fuel to the pump, coming out of the return when cranking, but I'm getting no fuel coming out to the injector lines which I have removed to assist in troubleshooting this. I changed the pump because the first one was doing exactly the same thing that this one is doing. I even went so far as to remove the plunger from the Fuel Stop Soenoid even though it was working fine. Also, to ensure that I'm getting fuel supplied, I put a low pressure inline Bugpack fuel pump to supply fuel to the inlet. What am I missing, or what can I do.
Also, The first pump is the one that was on the engine when I got it, and by the looks of it, it had been sitting for many years. As I understand it hasn't been on the road in a few years. The other pump came off the eco-diesel engine that I pulled from the Pick-N-Pull a few months ago, and that one appears to have been run somewhat recently, and when I took the lines apart, plenty of fuel came out of them.

Thanks

the pump internals could be sticking in either pumps. your best option would be to run either lubromoly diesel purge, or straight ATF in the pump. this does not mean simply filling the pump with either liquid and then running the diesel lines to it. it must be fed the PURE substance. the lubromoly diesel purge will most likely clear the pump up much quicker than ATF.

turbosyncrobus · « **Reply #2 on:** February 21, 2009, 06:18:20 pm »

Where do I buy diesel purge, I'm all over tring some of that. I would like to get the truck running, then I'll think about getting one of the pumps rebuilt. I just got this Caddy and it hasn't seen the road in many years and thus will need a little TLC to get it roadworthy. Thanks for the info.

Rabbit TD · « **Reply #3 on:** February 21, 2009, 11:58:53 pm »

Why don't you remove the banjo bolt for the return line on the pump and see if the pump is actually full of fuel, if it isn't just fill it through that hole and make sure the filter is actually full also. I doubt if you have the same problem on both pumps, probably just doesn't have fuel in it yet. Crack the injector lines a little and crank till fuel comes out of all 4 and then tighten them up and and then try to start it, Doesn't take near as long that way. Good Luck

turbosyncrobus · « **Reply #4 on:** February 22, 2009, 06:37:33 am »

Quote from: Rabbit TD

Why don't you remove the banjo bolt for the return line on the pump and see if the pump is actually full of fuel, if it isn't just fill it through that hole and make sure the filter is actually full also. I doubt if you have the same problem on both pumps, probably just doesn't have fuel in it yet. Crack the injector lines a little and crank till fuel comes out of all 4 and then tighten them up and and then try to start it, Doesn't take near as long that way. Good Luck

As I wrote in my original post, I do have fuel pumping out the return when I'm cranking the engine, that is how I know I have a good prime. Even though I have sufficient prime, I am getting virtually no fuel coming out of the pressure valves (I've removed the injector lines all together) whereas high pressure fuel should be shooting out. Yes, it does seem unlikely that two pumps in a row would have the same problem, but both pumps have been sitting idle for a very long time and this leads me to agree with what "jtanguay" wrote earlier.

Quantum TD · « **Reply #5 on:** February 22, 2009, 02:41:55 pm »

Just a few thoughts:

1) If you have not actually primed the pump (removed the banjo "OUT" bolt and filled the pump), then it will take some considerable cranking to get the car to start.

2) Even IF you primed the pump (as above), then it will take some considerable cranking to get a car to start if you have all the fuel pipes tight.

3) Fuel coming out of the return lines does not necessarily mean you have good prime. Most of the fuel that comes out of the return lines is excess fuel from the injectors. That fuel sits in the injectors until new fuel (or air) forces it out, thru the return lines, back to the OUT banjo bolt, and back to the tank. It should be noted that the residual fuel DOES NOT go back into the pump directly to be re-injected.

SO0ooo, you could still be pumping air into the injectors, and forcing the residual fuel out of the injector bodies, back to the pump.

I'd prime the pump with some diesel purge, or ATF directly into the top of the pump (what I always do). It will then take about 1-2 minutes of cranking to get the car to fire.

If it does not fire after 5 minuted of cranking, then you have several possibilities:

1) Bad glow plugs (have they been tested?)
2) Low compression (has that been tested?)
3) Slow starter speed

4) If #'s 1,2 and 3 above both check out, then you probably have stuck vanes in your injection pump. It doesn't take too much moisture and sitting to get them to stick. Even if your used pump had fuel run out when you removed it, it could have had water in it which could have rusted the internals after sitting dry for a while.

Also: it's worth noting that even when pumping, there really isn't a ton of fuel that comes out of the delivery valves. It's like a quick spritz of fuel from each valve, not a gush of fuel. So, double check that.

I've often found, when bench testing pumps, that if the pump is not COMPLETELY full of fuel, the upper two valves will take a while to start pumping. That may be the case with you. Your pump may be pushing air and some fuel that's in the pump, just not enough to be terribly visible on the motor after it comes out.

turbosyncrobus · « **Reply #6 on:** February 22, 2009, 09:07:36 pm »

Ok, after running a closed loop of ATF through the pump for most of today, I have ATF now pumping out of all but one valve (B) the upper forward. I'll let it sit overnight and see what happens tomorrow. But I do have a seep from the throttle area.

Quantum TD · « **Reply #7 on:** February 23, 2009, 10:00:50 am »

Quote from: "turbosyncrobus"

Ok, after running a closed loop of ATF through the pump for most of today, I have ATF now pumping out of all but one valve (B) the upper forward. I'll let it sit overnight and see what happens tomorrow. But I do have a seep from the throttle area.

You might need to take that valve out and look at it. Sometimes they stick. Just be careful when you pull it out, not to lose any parts. Here are some pics:

http://www.vwdieselparts.com/forum/viewtopic.php?t=6694

I've had experiences where the fuel would not come out of those upper valves, and I've had to pull them to find no problems. But, once I put them back in, they pumped fine. It also may be the case that you need to actuate the governor (throttle lever) to get enough volume to pump through the valve.

Let us know how it goes.

turbosyncrobus · « **Reply #8 on:** March 01, 2009, 08:11:05 am »

Well, as it turns out the IP is the least of the problems with this motor. I bought a diesel compression tester and tested the cylinders with some very dismal results; 1. 0# 2. 180# 3. 160# 4. 155#. I pulled the head off and discovered that every piston had an indentation from valve contact, the number 4 intake valve was pitting and looking really bad, and there was various pitting in some of the combustion areas in addition to the normal cracks between valves. I have already ordered the parts to rebuild the JX longblock that I had picked up a while back, and now I'm doing an engine swap that I really didn't want to get into right now. Additionally, I get to figure out why the flywheel doesn't turn as it should when I push the vehicle while it is in gear (I hear friction but there is much slippage and ocassional movement) hopefully it is just the clutch and isn't something else major.
And so the adventure begins