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Kevin in Atlanta 01-25-2019 12:26 PM

Leaking Injector - fuel puddle at manifold.
I typically pressurize the fuel rail by pulling the relay and jump 30 and 87 long enough to get 50+ PSI on my pressure gauge attached to expose fuel leaks when installed refurbished injectors. Most of the time there's no drama.

In this case the #5 puddled at the base of the injector after sitting overnight. I pulled the rail, replaced top and bottom o-rings, reassembled and pressurized the rail and the same thing happened again.

My understanding is that the injector is closed by default. So, there no way fuel could travel up the injector. I believe the injector itself is leaking above the o-ring.

Is this a documented failure?

Billu 01-25-2019 02:12 PM

Had a leak with my Ljet, replaced the hose and determined the injector itself was leaking.
I bought a used replacement from 928 Int.

Kevin in Atlanta 01-25-2019 03:02 PM

So, that seals it.


SeanR 01-25-2019 04:59 PM

Yep, had a few over the years. That's why it's important to test the system as you did.

worf928 01-25-2019 06:39 PM

Yup. Injectors can leak from not in the vicinity of the o-ring after ultrasonic cleaning.

Kevin in Atlanta 01-25-2019 08:08 PM

Well, had a injector refurbished and pressure is holding near 55psi for the past 15 minutes, I'll circle back later to see how it's doing.

I would like to point out a couple of things. One, order and use or supply the o-rings available from Roger. On three attempts I had a blowout from top o-rings provided by my injector refurb folks. I swapped theirs for Roger's and that worked.

Even though the o-rings looked the same they aren't?

Two, leave the rail pressurized overnight. This is not my normal practice, but because I had to wait for some parts I was lucky to see the pooling in the #5 injector hole.

Just my random thoughts.

Billu 01-25-2019 09:59 PM

Originally Posted by Kevin in Atlanta (Post 15592528)
So, that seals it.


or, actually, doesn’t

Kevin in Atlanta 01-26-2019 11:08 AM

This morning I found another injector hole with a puddle of gas around it. From this has never happened to 2 in the same rebuilt set. Makes me wonder.

More time to replace the injector harness ends I guess.

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