Help! Stock replacement injector problem

[RamThatStroker]

My cousin and I installed brand new stock replacement injectors in my 03. Truck runs smooth but seems low on power and is burning more fuel that it normally does. Any help would be appreciated...

 

[E7mack96]

probably got an injector tube a little loose, or maybe even overtorqued?

 

[SShafranko]

Are they new or Reman. ?

 

[RamThatStroker]

Injectors are new latest iteration (stainless I think). I'm going to go back and check all the torque on the injectors this weekend. After searching around the forums I found that some say that the injector tubes must be changed which we didn't do. could that be my problem

 

[E7mack96]

it could be, we replace tubes with every changeout. did u follow procedures as to installing them otherwize?



INSTALLATION

(1) Inspect fuel injector.

(a) Look for burrs on injector inlet.

(b) Check nozzle holes for hole erosion or plugging.

(c) Inspect end of nozzle for burrs or rough

machine marks.

(d) Look for cracks at nozzle end.

(e) Check nozzle color for signs of overheating.

Overheating will cause nozzle to turn a dark yellow/

tan or blue (depending on overheating temperature).

(f) If any of these conditions occur, replace injector.

(2) Thoroughly clean fuel injector cylinder head

bore with special Cummins wire brush tool or equivalent

(Fig. 22). Blow out bore hole with compressed air.

Fig. 16 CONNECTOR TUBE REMOVAL

1 - CONNECTOR TUBE

2 - TOOL #9015

3 - CYLINDER HEAD (LEFT SIDE)

DR FUEL INJECTION - DIESEL 14 - 87

FUEL INJECTOR (Continued)

(3) The bottom of fuel injector is sealed to cylinder

head bore with a copper sealing washer (shim) of a

certain thickness (Fig. 20). A new shim with correct

thickness must always be re-installed after removing

injector. Measure thickness of injector shim (Fig. 21).

Shim Thickness: 1. 5 mm (. 060”)

(4) Install new shim (washer) to bottom of injector.

Apply light coating of clean engine oil to washer. This

will keep washer in place during installation.

(5) Install new o-ring to fuel injector. Apply small

amount of clean engine oil to o-ring.

(6) Note fuel inlet port on high pressure connector.

This must be positioned towards intake manifold.

Position injector into cylinder head bore being

extremely careful not to allow injector tip to touch

sides of bore. Press fuel injector into cylinder head

with finger pressure only.

(7) Install fuel injector hold down clamp and hold

down bolts. Alternately tighten clamp bolts to 10 N·m

(89 in. lbs. ) torque.

(8) Connect injector solenoid wires and nuts to top

of injectors (Fig. 18). Tighten connector nuts to 1. 5

Fig. 17 TOOL #9015 AND CONNECTOR TUBE

1 - CONNECTOR TUBE

2 - LOCATING PINS

3 - RUBBER O-RING

4 - TOOL #9015

Fig. 18 FUEL INJECTORS

1 - SOLENOID CONNECTIONS

2 - ROCKER HOUSING

3 - FUEL INJECTOR

4 - PASSTHROUGH CONNECTOR

Fig. 19 FUEL INJECTOR REMOVER - #9010

Fig. 20 FUEL INJECTOR SEALING WASHER (SHIM)

LOCATION

1 - FUEL INJECTOR

2 - COPPER SEALING WASHER (SHIM)

14 - 88 FUEL INJECTION - DIESEL DR

FUEL INJECTOR (Continued)

N·m (14 in. lbs. ). Be very careful not to overtighten

these nuts as damage to fuel injector

will occur.

(9) Install exhaust rocker arm assembly.

(10) Set exhaust valve lash. Refer to Engine.

(11) Install high pressure connector and its

retainer nut. Tighten nut to 50 N·m (37 ft. lbs. )

torque.

(12) Install high pressure fuel line. Refer to Fuel

Line Installation.

(13) Install valve cover. Refer to Engine.

(14) Install breather assembly.

(15) Connect negative battery cables to both batteries

 

[RamThatStroker]

Didn't clean out the bore because bore looked clean to me when we did it. Other than that we followed the directions as written.

 

[CoastyAV8R]

If the injector tubes are in good shape, many people don't change them out. I didn't change mine when I did my injectors. The biggest variable is whether or not you used a torque wrench on the tubes and injectors and the brass washer on the injectors were all in place. If you follow the procedures listed above step by step and use the torque wrench (no short cuts to save time) you should be fine. One other possibility is are you the original owner? If not, you stated you put all new stock injectors, perhaps the ones you replaced were high performance injectors which would explain the difference in power. Why did you change the injectors?

 

[RamThatStroker]

At little update about my truck,



Purchased new injector tubes and installed this weekend. Removed exhaust rocker, broke loose injector, torqued tube nut to 11ft/lbs, torqued injector hold down bolts to 89in/lbs, torqued injector tube nut to 37ft/lbs, reinstalled rocker and torqued 27ft/lbs. Put back everything restarted and took for a ride. Truck seemed low on power again and was "knocking". Repeated above procedure once again and found #2, #4, #5, and #6 injector hold down bolts loose and all #2, #3, #4 hold down bolts loose. Took truck for a ride and truck seems normal Now hopefully it stays that way. Is there any reason why they would be loose #@$%!

 

[RamThatStroker]

If the injector tubes are in good shape, many people don't change them out. I didn't change mine when I did my injectors. The biggest variable is whether or not you used a torque wrench on the tubes and injectors and the brass washer on the injectors were all in place. If you follow the procedures listed above step by step and use the torque wrench (no short cuts to save time) you should be fine. One other possibility is are you the original owner? If not, you stated you put all new stock injectors, perhaps the ones you replaced were high performance injectors which would explain the difference in power. Why did you change the injectors?

Stock ones looked good but I went ahead and replaced them anyways (see previous post). Used a torque wrench on all except the electrical wire hold down nuts (put them on snug) and fuel lines. We insured the brass washers were in place before installation but did not blow out the bores or clean with the special brush as the service manual calls for (visually looked down bore holes and everything seemed clean). I am the original owner and had to replace injectors due to two bad stock ones(told by dealership). Decided to replace all 6 with new stock replacements (purchased from Wicked diesel). Seems to be running ok now but we had to go back and retorque everything immediately after installing the new torque tubes. Any thoughts??



Thanks,

 

[CoastyAV8R]

At little update about my truck,



Purchased new injector tubes and installed this weekend. Removed exhaust rocker, broke loose injector, torqued tube nut to 11ft/lbs, torqued injector hold down bolts to 89in/lbs, torqued injector tube nut to 37ft/lbs, reinstalled rocker and torqued 27ft/lbs. Put back everything restarted and took for a ride. Truck seemed low on power again and was "knocking". Repeated above procedure once again and found #2, #4, #5, and #6 injector hold down bolts loose and all #2, #3, #4 hold down bolts loose. Took truck for a ride and truck seems normal Now hopefully it stays that way. Is there any reason why they would be loose #@$%!

If the injectors weren't seated properly you could have gotten a false torque reading on the first go around, other than that I can't imagine why they would come loose if torqued correctly.

 

[DonFitzwater]

If the injectors weren't seated properly you could have gotten a false torque reading on the first go around, other than that I can't imagine why they would come loose if torqued correctly.

Oil in the bolt holes?