LLY: Help me spot this leak

cstephens93

New member
Oct 13, 2014
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Anybody have any clues as to where this leak could be coming from? I've replaced the bleed screw from the plastic one to this aluminum one from Kennedy. I've rebuilt the filter head several months ago hoping to stop this leak before.

Didnt really worry about it, but now that ive seen I cant seem to make the desired 26kpsi rail pressure on Robs race tune, I'm thinking this may have something to do with it.

In the picture you can clearly see where there is fuel
 

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countrycorey

Trust Me I'm an Engineer
Jan 30, 2010
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LA
It looks like it needs new o-rings around the plunger


2007 Chevy Classic CCSB LS 4x4 w/ LBZ & 6 Spd Ally
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Banks RamAir Intake
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MBRP 5" DP Back...What cat
PCV Rerouted
EGR Blocker & Fingerstick
Retro Solutions 6000K in Low Beams
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AutoMeter Phantom II Boost and EGT on A-Pillar
Hammerhead Armor Replacement Front Bumper
EFILive from IdahoRob
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ProFab Y-Bridge and 3" Cold Side Boost Tube
 

SoCalMike

Member
Dec 12, 2010
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SoCal
I was thinking primer plunger o-rings as well.

It looks like it needs new o-rings around the plunger


2007 Chevy Classic CCSB LS 4x4 w/ LBZ & 6 Spd Ally
Greystone Metallic
295/70/17 Nitto Trail Grapplers on Chrome H2s w/ LMM Centers
Custom CamLocker Toolbox
Grizzly Nerf Bars
Pioneer 4100 Head Unit
JL Audio Components
Sportsman Max4 Seat Covers
Banks RamAir Intake
Tinted Windows
MBRP 5" DP Back...What cat
PCV Rerouted
EGR Blocker & Fingerstick
Retro Solutions 6000K in Low Beams
Nicktane 1 Micron Filter & Adapter
Banks Hot Side Intercooler Tube
AutoMeter Phantom II Boost and EGT on A-Pillar
Hammerhead Armor Replacement Front Bumper
EFILive from IdahoRob
Fleece All On Mod
ProFab Y-Bridge and 3" Cold Side Boost Tube
Me 3
 

cstephens93

New member
Oct 13, 2014
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Tallahassee, FL
Considering the age of the truck it might just plain be worn out and a seal kit may or may not work, new ones with filters are around $120.00

New filter heads? As in the whole thing? What vendor should I contact for a new one?

If system is losing enough fuel (volume), I would think its a possibility.

Yeah, I'm not sure. My truck doesnt drain the pressure. It just doesnt make enough rail pressure. See attached image
 

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countrycorey

Trust Me I'm an Engineer
Jan 30, 2010
1,512
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LA
Considering the age of the truck it might just plain be worn out and a seal kit may or may not work, new ones with filters are around $120.00


I had to replace the filter head on my dads LLY due to the plunger leaking. I got that one at the dealership, but only cause I needed it yesterday when it happened.


Corey
 

c20elephant

C20ELEPHANT
Apr 25, 2013
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New filter heads? As in the whole thing? What vendor should I contact for a new one?



Yeah, I'm not sure. My truck doesnt drain the pressure. It just doesnt make enough rail pressure. See attached image

Pretty sure this is a LLY LBZ number, Google this number



Genuine GM 12642624 Fuel Filter
 
Last edited:

Robby Avery

GM TECH @ FENDER GMC
Jul 31, 2008
820
2
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Norman Park, Georgia
How sure are you the filter housing is not leaking possibly cracked? Do you have a fuel pressure test port gauge that Kennedy diesel offers or any other special tool to check pressure while priming and vaccume while start to determine weather or not you have a leak? Also if you have a way to to access fpr data you can monitor it and see how it's acting I used the gm tech 2 at work and check my wife's lb7 GM calls for a shark tooth pattern which is pretty much a dead give away that the fpr is sending sewced signals or its on it way south my wife's truck has the lopey surging idle which is what is caused by sewced signal truck runs fine just lopes at idle and doesn't seem to pull like it used to at wot so a new fpr is what Ill do when funds allow
 

cstephens93

New member
Oct 13, 2014
677
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Tallahassee, FL
How sure are you the filter housing is not leaking possibly cracked? Do you have a fuel pressure test port gauge that Kennedy diesel offers or any other special tool to check pressure while priming and vaccume while start to determine weather or not you have a leak? Also if you have a way to to access fpr data you can monitor it and see how it's acting I used the gm tech 2 at work and check my wife's lb7 GM calls for a shark tooth pattern which is pretty much a dead give away that the fpr is sending sewced signals or its on it way south my wife's truck has the lopey surging idle which is what is caused by sewced signal truck runs fine just lopes at idle and doesn't seem to pull like it used to at wot so a new fpr is what Ill do when funds allow


I dont have any of Kennedys tools.....they are kind of pricey. But I do want one.

I dont have a tech 2 but I have an autel maxsys scanner and I have a v2. could i use the V2?
 

295PRO

New member
Jan 30, 2015
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It looks like it needs new o-rings around the plunger


2007 Chevy Classic CCSB LS 4x4 w/ LBZ & 6 Spd Ally
Greystone Metallic
295/70/17 Nitto Trail Grapplers on Chrome H2s w/ LMM Centers
Custom CamLocker Toolbox
Grizzly Nerf Bars
Pioneer 4100 Head Unit
JL Audio Components
Sportsman Max4 Seat Covers
Banks RamAir Intake
Tinted Windows
MBRP 5" DP Back...What cat
PCV Rerouted
EGR Blocker & Fingerstick
Retro Solutions 6000K in Low Beams
Nicktane 1 Micron Filter & Adapter
Banks Hot Side Intercooler Tube
AutoMeter Phantom II Boost and EGT on A-Pillar
Hammerhead Armor Replacement Front Bumper
EFILive from IdahoRob
Fleece All On Mod
ProFab Y-Bridge and 3" Cold Side Boost Tube
I've had the issue. If I park with front of truck high than back. It loses it prime. A few pumps on primer and it works. while pumping primer I see bubble coming the red wire boot. Any ideas
I was thinking primer plunger o-rings as well.