Air in supply line coming from injection pump right after being shut down. 1.6na

[81dzlcaddy]

Got a clear line on the supply line to the injection pump to make sure there is no air in the causing my issues of rough idle. Got the truck started and running and got fuel going through the line and watched it to see if it was leaking any air in to the line both at idle and under acceleration. There was no air in the line while running so nothing was sucking air. When i shut the truck down air comes out of the pump and the fuel moves about four inches away from the inlet back to the filter and stopped. I was wondering if this is normal as i have never had a clear portion of line on the truck. I had to leave right after shutting the truck down so i do not know if it moved any more i am going over to check shortly. Could there be a like in the injection pump itself allowing air to get in to the fuel and cause the rough idle and the air to go in to the line when shut down. The truck also takes a couple cranks more than it use to to get it started. The engine is rebuilt and awaiting a compression tester to check and make sure the compressions good. Any help will be great. thanks in advance

[air-cooled or diesel]

sounds like the air in your system is the main problem and that it is abormal, solve it first and then you may have no problems.

[air-cooled or diesel]

open upper timing cover and see if its wet near inj pump, turn engine small amount so a big 'hole' in inj pump gear is down and get a light on 'it'. also change fuel filter?? check all connections of fuel filter are snug, and 1 screw on top is tight and bottom is snug too. cracks in line feeding ip? hope not.

[Rockerchick]

So a 4" bubble? That seems a little much. We get a small bubble every now and then on our TD but doesn't seem to affect starting or anything. When we had larger and more bubbles before the rebuild though, it was a bit rough.

Make sure all of your connections are tight at the fuel filter and IP. Was the IP rebuilt as well?

[81dzlcaddy]

It was about three years ago when i bought it. Took it off the truck for about a month to rebuild the engine and now i have this issue with the truck. I am awaiting my compression tester to try and rule out the engine having low compression. I did have the truck running with no air in the supply line until i shut it down. My worry is the pump is sucking air through a seal causing the rough idle and the air to come from the pump in to the supply line.

[air-cooled or diesel]

right; only you may have to remove gear to see leak, dont do it with out knowing how to do it!
turn motor over and look thru big openings of gear maybe you can see moist made by a possible leak, use a light and look at bottom esp

[Glegor]

right; only you may have to remove gear to see leak, dont do it with out knowing how to do it!
turn motor over and look thru big openings of gear maybe you can see moist made by a possible leak, use a light and look at bottom esp

dont listen to this guy, hes wrong!



its an air leak somewhere..

could be coming from your feed/return lines, or from your pump input shaft seal..

[81dzlcaddy]

I will check my return lines as i did not think they matter much on air getting in. I thought it was just the supply line. I will check those. If no change and i find out my engine has proper compression then i will just order another pump. I have had pumps leak diesel but run fine. Never had on that doesnt leak that i know of but runs like crap. Oh well i will stick with it. I am bound to fix it at some point lol. Thanks for the help folks

[air-cooled or diesel]

dont listen to this guy, hes wrong!



its an air leak somewhere..

could be coming from your feed/return lines, or from your pump input shaft seal..

how am i wrong you practically said same thing

[air-cooled or diesel]

right; only you may have to remove gear to see leak, dont do it with out knowing how to do it!
turn motor over and look thru big openings of gear maybe you can see moist made by a possible leak, use a light and look at bottom esp

bottom of pump thru a big 'hole' in gear

[manandfox]

I used to get air in my lines after I got my 1.6D (running no less) and found when doing a tune up that the PO had replaced the fuel filter and didn't notice the o-ring didn't come off the first filter. Basically the o-ring in the center was double stacked so the outer one wouldn't seal. I've heard this isn't uncommon for people to have done this.

[davidm2232]

i'm having the same issue. i put on a different injector pump and replaced all the return lines last night. problem is now worse. did you find out anything?