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P pump not working after reinstall

2K views 34 replies 6 participants last post by  BSH 
#1 ·
Hello,

Put the P pump back on the truck after a bunch of engine work and it is not pumping. Torqued the nut to 170 foot pounds, installed a new air dog which is supplying adequate fuel to the pump. Also I removed one delivery valve and turned on the air dog and fuel shot out of it like a fountain. But for whatever reason when I put the delivery valve back in and tighten it down fuel will not shoot out of the barrel into the injection line when turning the engine over.

This is day three of pissing around with this, if anyone has any tips I would really appreciate it. Shut off solenoid is working, and just to confirm I removed it and pull the lever up with zip ties. Still nothing. When I push the shut off solenoid down I can feel some springy resistance so I don’t think the rack is stuck.
 
#3 ·
After about 30 ten second attempts with the starter there was a bit of wetness but when I tightened them again it wouldn’t start
 
#5 ·
Correct, I just put in new ones. And confirmed twice with power driven diesel that the big side goes down and the pin goes in the top
 
#6 ·
Also, I just pulled the fuel filler out and took a video and it definitely is turning the injection pump Gear.

Thanks for your help btw
 
#7 ·
I mean oil filler
 
#9 ·
If you are referring to the return line from the top passenger side front end of the P pump, I have installed a rubber line onto the hard line which then t’s into the injector return line and then heads back to the tank. I have tried disconnecting the hardline from the P pump and turning the key forward which then shoots Fuel out like a fountain. I have also disconnected it from where it tees into the injector return line and the line going back to the tank and lots of fuel shooting out there also.
 
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#11 ·
Finally started getting good fuel flow at the injectors. Haven’t been able to start it yet but at least it’s coughing a bit like it wants to. I guess it must’ve just been an air bubble from hell I have no idea how it took this long to come out.
 
#12 ·
Thanks for your help, much appreciated
 
#13 ·
Sounds like you have it right. Keep cranking it! It usually takes me 2-3 minutes of cranking to get the motor started after a pump removal. And I am flooring it the whole 3 minutes. Then it spits and sputters while I floor it for another minute and then can idle on it's own. Whole process takes about 5-6 minutes before its idling clean. Try this and report back.
 
#14 ·
Well, starting to make some progress. After at least a dozen rounds with the starter going for 15 to 20 seconds it’s starting to cough some black smoke and sounds like it wants to start. I think if I spend an entire day tomorrow trying to get the air out of more of the injector lines I should be able to get it going. What a nightmare. Now it’s three full days of trying to get this piece of $/@! to start
 
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#15 ·
Another full day in the books. Pretty sure all air is out of the lines. Had my wife turn it over while I tightened the nuts as diesel was flicking out. Still no starting though, just lots of smoke. Had it so close to starting a bunch of times but it just won't take. I even put the timing back 5 degrees to where it was (13 degrees according to info plate) and still no start just whiter smoke. I'm starting to think that I have too much fuel to start.

My new twin turbos are severely back ordered and I purchased delivery valves and injector based on them.

Do you think 5 x 0.016 injectors and 7mm delivery valves are to much for stock turbo/airbox?

Thanks again
 
#20 ·
Another full day in the books. Pretty sure all air is out of the lines. Had my wife turn it over while I tightened the nuts as diesel was flicking out. Still no starting though, just lots of smoke. Had it so close to starting a bunch of times but it just won't take. I even put the timing back 5 degrees to where it was (13 degrees according to info plate) and still no start just whiter smoke. I'm starting to think that I have too much fuel to start.



My new twin turbos are severely back ordered and I purchased delivery valves and injector based on them.



Do you think 5 x 0.016 injectors and 7mm delivery valves are to much for stock turbo/airbox?



Thanks again
I'm staring to think your method of timing is why it is not starting. Please try pin timing the pump to the engine first before trying anything else.

Sent from my LG-H932 using Tapatalk
 
#16 ·
https://youtu.be/UeNQvNGjaYg
 
#17 ·
I recall a thread very similar to yours where the OP swore he was using compression TDC to set his pump, then discovered he wasn't.
 
#19 ·
I tried a few times with the pin but could not get it to go in. Even with the valve covers off and watching the rockers to get a rough idea of where it should be.

So I pulled the head and did it with a dial indicator. Then removed the pump and cam. When I had the pump off I tried moving the shaft by hand just to see how tight it was and it wouldn’t budge. I took pictures before and after to line it up exactly to the tooth by zooming in. I only moved it enough to find the top and then didn’t move it while the cam was out.
 
#22 ·
So I pulled the head and did it with a dial indicator. Then removed the pump and cam. When I had the pump off I tried moving the shaft by hand just to see how tight it was and it wouldn’t budge. I took pictures before and after to line it up exactly to the tooth by zooming in. I only moved it enough to find the top and then didn’t move it while the cam was out.
You pulled the head, the cam and the pump to find TDC? Huh??? Finding which stroke you are on is as simple as watching valve overlap.

You can fab up a tool to turn the pump shaft. I use it to speed up timing changes.
 

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#21 ·
Thanks, will do. I sent that video to power driven diesel and the guy I spoke with said it’s a classic case of pump not being timed.

I really appreciate the help, have a great day
 
#23 ·
Head had to come off anyways so I just followed the method used by Hamilton Cams. Just did Cam, lifters, pushrods, head studs, valve springs and head gasket. Cool tool, just researching now.
 
#25 ·
Ok thanks, did you fill the cylinder with compressed air to get the spring back on? I was leaning towards the dial indicator down the injector hole as I have the big c clamp style valve compressor that requires the head to be off. Just need to figure a way to extend my dial indicator.
 
#28 ·
#27 ·
Ahhh, right on thank you.
 
#29 ·
Well, I’m embarrassed to admit this but as I was getting the timing finished I noticed that I didn’t connect the linkage to the AFC. It’s running now and I just did the break in procedure for my new cam. Going to change the oil and go for a rip, the thing feels very snotty.

I appreciate everyone who tried to help.

Thanks
 
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