I noticed a couple of my injectors are leaking slowly! Any recommendations on what to do? Its a 90 7.3 idi. Thanks for your help

 

Where are you noticing the leaking, injector lines or return lines? A return line kit is pretty inexpensive; you get new connections, rubber lines, and O-rings. The injector lines are more expensive and have to be ordered for the cylinder that is leaking.

Any trouble starting the truck after it sits a couple hours or overnight? that would mean fuel is leaking out of the lines and leaving air in its place.

 

it was not leaking from the metal fuel lines. it looks like its squezzing out of where the injector screws down to the "Manifold???" I am not sure what its called but its like a manifold is on gas engine

 

which injectors are doing this? The cylinders are numbered 1-3-5-7 on the passenger side front to back, on the drivers side they are 2-4-6-8 front to back.

The reason I ask is on my truck there was some fuel in the valley pan (area beneath the intake manifold) that kinda collected at the back (between cylinders 7 and 8). Found that the injection pump had a bad o-ring on the supply line.

 

i saw a little squeezing out of 7 i know and i think 4 on the drivers side. I know 7 was leaking

 

Hard start?

 

nah not really. I mean when its cold it takes a few turns but i wouldnt say its hard. I figured maybe b/c its been a little cold outside

 

Would you consider replacing the injector? If you do that, it would be a good idea to replace the fuel return lines for all your injectors at the same time.

Replacing the injector will tell you what the thread situation is in that injector hole, if the injector is cracked, or if you have a dead cylinder.

Moderators - Would carbon buildup on the pre-cup close it off sufficiently enough to cause the fuel to weep out the threads rather than blow through to the cylinder?

 

are the fuel return lines the rubber hose stuff? if so i just had all that replaced

 

actually number 7 metal line is leaking a little

 

Hi,the return line kit sounds like a good approach most common cause of those kind of leaks comes from the 2 o-rings on the top of each injector under the plastic caps.pretty easy and cheap fix.I would start there.good luck.

Norm

 

I would buy a return line kit and install all of them if you try to just do the ones that are leaking more will start leaking when you disturb them and it will never quit.

 

I think its unlikely that the injector is leaking from the high pressure side. If it was the engine would not run right. Leaks at the return lines don't always cause hard start problems. My truck has slightly wet O ring connections under a few injector tees and and it still starts fine. I think you have injector O rings that are leaking. If they were recently replaced, then its possible that some were not seated properly to seal in place. I had that happen too and it was enough to push a pretty steady stream of fuel out from the connection.

Not a big deal to fix, but you might have to take a closer look at the offending fuel return tee and the O rings under it. Look how high the tee is on the injector body and compare it to the other ones to see if its seated down all the way. If it is all the way down, then you might have to take the tee off again and inspect the O rings or the tee itself for damage. Any scratches of nicks could prevent a proper seal.

 

What about lubing the o-rings up before putting the tee's on? A little diesel fuel, atf, vaseline, motor oil - just to get the plastic cap on without binding the o-rings?

 

Lube is always a good idea when assembling parts with O rings (as long as its not in the cooling system). Diesel tends to be a little sticky if you push too hard when installing the tees. A little gear oil or clean grease would probably help.