1990 F350 7.3 LEAKING AT TOP OF INJECTOR/S Losing my mind on this ....

[TwinForks90F350]

Hello folks, Chris from Long Island here. Been a lurker for while and have learned a lot so finally got a chance to join.
I've seen lots of threads on leaking injectors, bad caps, soft lines, hard lines and o rings and even some mention of worse leaks after a change in the return line kit and now find myself in the position of having a leaky #2 injector, at the top, after several attempts at changing everything. #3 might be developing a slight leak as well ( I've gone over it , and over it and then some, yet the leak seems to get worse. Used Vaseline to lube the o rings, checked the hard lines and cap for cracks, checked and rechecked the threads, clamps and lines. Still leaking. Gonna go over it one more time this afternoon piece by piece and then I'm totally lost. Was trying to avoid another big expense this summer but may find myself at the mercy of the mechanics, ( shop work tends to get real expensive in these parts if you don't really know who is working on your rig ). Anyway, maybe I missed something. Hoping someone might have some info to help before I take it to a shop.

There is also another issue with the new Tranny that I'll start in a new thread once this nightmare is resolved. Seems nobody can figure that one out either and it's been to half a dozen shops, including the re builder. Thanks in advance. Glad to have finally joined. Chris

 

[IDIoit]

if you have properly installed new return lines, I would check the injection lines themselves.
if you have a burr on the tip, it will never seal.

 

[BDCarrillo]

Leaking at the top... Of what? The return line cap or hardline nut?

 

[chris142]

buy the kit from here and not the junk kits from the auto parts store

 

[mntwins7]

make absolutely sure those plastic caps are tight on the o-rings.

 

[pickupman]

Make sure that you didn't cross-thread any of the hard lines onto the injectors. I accidentally did that on one of the flare nuts and it actually cracked, creating a leak that I couldn't see at first. Eventually I noticed the crack. Never again will I make that mistake.

 

[turbo elk]

Make shure the nipple on the end of the hard lines point straight at the top of the injector, you might have to bend them to line them up.

 

[riotwarrior]

An insoection mirror under injecotd line to ensure TIP of line is not damaged carefully inspect the line NUT for damage and tip of injector.

Removing the hard line clamps allows a bit more flex...do not bed o far though..and always put line clamps back in place once repair is completed.

U cqn test run without clamp to inspect for leaks however do not run for long period of time.

Make sure no casting flash is inside plaztic return cap...the small seam from being made...lit sanding with fine paper can remove that burr and new O rings and golden

Top O ring on first..then roll lower o ring over top one.

Good luck

Oh ya welcome

 

[Wvdirtroad]

How old are the injectors?

 

[OLDBULL8]

riotwarrior got it right.

If the truck has been run without the line clamps, the line will crack eventually at the nut, either at the injector or IP connections. The hard lines are thick and hard to see a cracked one.

The hard lines MUST be lined up almost perfect so that the "flare" goes straight into the injector. Cocked to one side or the other, they will not seal no matter how tight the nut is.

The return rubber lines must be short enough so they don't push "distort" the cap, there is only .004 to .006 seal on the o'ring.

If you can't screw the nut on by finger all the way, more then likely the hard line is not lined up.

 

[riotwarrior]

Bill dont say that...now everyone will expect it...

 

[OLDBULL8]

Kudos are due to those who knew.

Ya got your Busted Knuckle sign up yet? Should change your Avatar to that.

 

[texcl]

I thought I had a cap leaking once, it ended up being the return line (which wasn't wet). I always have spare line in the glove box so I tried it for good measure and sure enough it fixed it. I always try for the simple remedy first.

 

[icanfixall]

The plastic caps will usually need an exacto knife to cut away the casting flash in the edges. Leaving that usually cute the o ring. I scrape away any flash long before I try to push the cap on the greased o rings. Adding the top one first and rolling the bottom one over the top is the correct way. Any misalignment of the nut to the injector will cause a cross thread. So bend the lines to fit easily and press down on the line into the injector flare. then screw the nut all the way down. An easy way to bent the line is slip a 5/8 wrench over the nut to the line. then bend slightly till it fit. If a nut gets cross threaded you will need to remove that injector and clean up the threads with a knife edge file. The nut is very hard material and it ruins the softer injector threads easily. The vibration clamps must be on the hard lines or you will break a line usually right below the nut where you can't see it. Not a chance of repairing a broken line either. That compression flair is made as part of the line. I broke a line and tried to grind the flair down to see the crack.. Nothing doing. Flair is part of the line. I sure would like to see the machine that makes these 10 different lines and how they bend them. Reason we have 10 lines is there is 2 different number one lines and 2 different number 4 lines. The trucks and vans use a different line so no way these lines can be used on other rigs unless you know how to make them fit.

 

[TwinForks90F350]

Overwhelmed at all the responses. Thanks to all. Took the 90 to a shop at 630 this morning. they started checking her out at 7. By 8 I pulled the plug since they said I would need an IP and all new hard lines,,,and return lines. I didn't wait for the price. There was never any doubt about the leak being top end, probably invisible,,,,the problem was my inability to find it. So, took it to a good friend, drinkin buddy and basically bribed him to check my rig out. 15 minutes in and he bailed,,,,, called a guy that was "older than dirt " so he said. Told me to go an get breakfast,,,,,again ! So I did. One hour later I get the call and of course he wants to play with me. Finally he says the truck is done, but doesn't tell me what the origin of the leak was. I get back, he hands over the keys, says give me 50 and shake this guys hand. The guy was no less than 70 and standing off to the side. I did as he asked. The guy says "so youre the one that appreciates us older folk , call me Monday and lets meet to talk about the Christine transmission".
I agreed and left in awe !
The hard line had a fractional crack, virtually impossible to see so the old man said. Said the plastic caps were fine but needed a slight filing before they too started to leak. O rings were brand new, and they were. Soft lines on the return were new but he found two areas that could be problems.

Think the leak is done. So glad. Thank you for all the responses and guidance. Very glad that this forum exists. It means a lot to so many people. Hopefully I can contribute as time moves forward.