Leaking injector return

John_piv

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Hey y'all, my way into work this morning I was running WMO when the truck starred surging a bit. Switched it over to plain diesel and smelled diesel the whole way in to work. I pull in, pop the hood, and sure enough; the rear driver injector is soaking wet.

(Wet injector and dry injector pictured for comparison)

My guess is the cold oil was too thick and clogged the injector return. I'm at work right now, can I take the two hoses off and blow everything out with injector cleaner or would that hurt something?

Thanks!
 

Jesus Freak

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Replace the o rings. It's just one of those things that you have to do on these trucks from time to time.
 

John_piv

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Replace the o rings. It's just one of those things that you have to do on these trucks from time to time.
Which O-rings? The rubber return line rings on the injectors were replaced earlier this year. Y'all mean the little ring connecting the metal return lines? If so, where do I find one?
 

Jesus Freak

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It happens. If you used regular rubber o rings it's not far out that they only lasted a year. The guys on here recommend a type of o ring made of something that starts with a "v". The cap itself can also start leaking somehow, it's a mystery but that happens to. And if you're running WMO like me, that stuff is tough on regular rubber. Also the bucking is probably a clogged fuel filter and the regular diesel "cleaned" the filter a bit so the IP would stop sucking air.
 

Old Goat

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You can buy the in bags of 50 for around 10 bucks.
size 111 part# 9464k24




Goat
 
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Black dawg

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I have been using buna orings out of the same bulk bag for close to 15 years now.
No issues. Maybe I am lucky??
 

SkylabTech86IDI

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It happens. If you used regular rubber o rings it's not far out that they only lasted a year. The guys on here recommend a type of o ring made of something that starts with a "v". The cap itself can also start leaking somehow, it's a mystery but that happens to. And if you're running WMO like me, that stuff is tough on regular rubber. Also the bucking is probably a clogged fuel filter and the regular diesel "cleaned" the filter a bit so the IP would stop sucking air.
I’ve started wondering about more long term replacements for these plastic caps…

Surely the plastic deforms with thermal cycles, thus (potentially/likely) contributing to leaks…

I guess that’s what the 2 O-rings for each injector are intended to remedy, but a 6-18months out of a set of rubber o-rings doesn’t scream “bullet proof reliability”.

So to my point, I’ve been wondering are there more permanent solutions to the 6.9IDI/7.3IDI fuel return system’s plastic caps, temperamental o-rings, and rubber lines & loosening clamps????? And if so, is it worth the investment if I plan on keeping this truck for the next 20 years?
 

Jesus Freak

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I’ve started wondering about more long term replacements for these plastic caps…

Surely the plastic deforms with thermal cycles, thus (potentially/likely) contributing to leaks…

I guess that’s what the 2 O-rings for each injector are intended to remedy, but a 6-18months out of a set of rubber o-rings doesn’t scream “bullet proof reliability”.

So to my point, I’ve been wondering are there more permanent solutions to the 6.9IDI/7.3IDI fuel return system’s plastic caps, temperamental o-rings, and rubber lines & loosening clamps????? And if so, is it worth the investment if I plan on keeping this truck for the next 20 years?
The 2 o rings are, one above the return port and one below the return port. And yeah, apparently there are some type of return lines that are expensive but more lasting. They were mentioned in a recent thread about leaking return lines. They're called "r&d".
 

IDIBRONCO

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So to my point, I’ve been wondering are there more permanent solutions to the 6.9IDI/7.3IDI fuel return system’s plastic caps, temperamental o-rings, and rubber lines & loosening clamps?????
There's no way to get around the o-rings since they do the actual sealing. R&D IDI Performance offers some aluminum return rails where you only need one per side. Someone on here (I can't remember his name) makes some brass return caps. You used them just like the plastic ones, one per injector.
And if so, is it worth the investment if I plan on keeping this truck for the next 20 years?
That's a question that ONLY you can answer. It's your truck, your money, and, ultimately, your decision.
I guess that’s what the 2 O-rings for each injector are intended to remedy,
No. The reason why there's two o-rings per injector is extremely simple. One is the upper seal, one is the lower seal, and the unused fuel stays in between them as it moves back to the fuel tank.
 

Black dawg

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I guess that’s what the 2 O-rings for each injector are intended to remedy, but a 6-18months out of a set of rubber o-rings doesn’t scream “bullet proof reliability”.
To me it "screams" installer error.

I think alot of times, guys get the hose lengths wrong and the cap is being held one way or another. As in not square with the injector.
 
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Old Goat

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There are the Brass caps from I think is "Dregs Garage".
he has a couple YT Vids showing them.
pricey, but will last for ever.

Last time I replaced the rubber hose between caps, I bought some rubber (not cloth covered) and it is in a roll, and will keep it`s curvature.
It will keep the curve, but I installed one to have the slight curve one way, and the next piece the other way. It keeps it in a pretty straight line, and haven`t had any leaks with the hose or "O"Rings.

Hope this helps some one .....


Goat
 

SkylabTech86IDI

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To me it "screams" installer error.

I think alot of times, guys get the hose lengths wrong and the cap is being held one way or another. As in not square with the injector.
Yeah I’d agree with that - it’s easy to underestimate how much longer rubber hoses push the caps out the way.
 

Azidiguy

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I’ve started wondering about more long term replacements for these plastic caps…

Surely the plastic deforms with thermal cycles, thus (potentially/likely) contributing to leaks…

I guess that’s what the 2 O-rings for each injector are intended to remedy, but a 6-18months out of a set of rubber o-rings doesn’t scream “bullet proof reliability”.

So to my point, I’ve been wondering are there more permanent solutions to the 6.9IDI/7.3IDI fuel return system’s plastic caps, temperamental o-rings, and rubber lines & loosening clamps????? And if so, is it worth the investment if I plan on keeping this truck for the next 20 years?
R&D makes some aluminum rails that are pretty nice still uses o ring though.
 

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