LB7 Injector test not installed

[Charp30]

I’m currently putting back together a stock LB7 and wanted to test the injectors before I install them. Is there anyway to verify they are good before I install and have to tear it back apart?


Sent from my iPhone using Tapatalk

 

[Bdsankey]

You can send them out and pay roughly $50 to $75 per injector to baseline test them.

 

[Charp30]

Thank you, I’ll look into sending them off.


Sent from my iPhone using Tapatalk

 

[N2BRK]

S&S will change the nozzles without adding to their clean and test service price. So it’s a good time to go to SAC nozzles and let them take care of it.

 

[Charp30]

I did a quick search for that and came up with nothing on how to get quotes and information.
How would I go about getting that information?


Sent from my iPhone using Tapatalk

 

[1FastBrick]

It's listed under the FAQ area of the website. Fill out the forum below and send it in. you can always call if you have more questions.


Can S&S Diesel Motorsport test and repair injectors?

No matter how big, small, or the application; if it’s a common rail injector or pump, we can test it. S&S Diesel Motorsport has the equipment and expertise to diagnose and fix most common rail fuel system issues. Baseline testing starts at $60 per injector and $195 per high-pressure fuel pump. Please fill out a Testing Work Order Form and include it with the hardware you need tested. PLEASE DO NOT ATTEMPT TO CLEAN THE NOZZLES. Nozzle spray holes are extremely precise and sensitive to abrasives.

https://ssdiesel.com/wp-content/uploads/2023/08/Testing-Work-Order-Form-SS-Diesel-Motorsport-4AUG2023.pdf

 

[Bdsankey]

I am an S&S dealer and can easily get you squared away with what you're looking for @Charp30 .

 

[1FastBrick]

There you go! Brad can assist you with the process. He is very familiar with this.

 

[Charp30]

Whatever help is appreciated.
I got the truck 8 months ago. About a month later the u joint failed and trashed the bell housing and rear plate. Sat in my garage since. Drained all the fluids and found oil/coolant mixed on both sides. Decided to pull the engine to do all gaskets, head studs, water pump, oil cooler ect. Started reading into the LB7 so I’d like to check the injectors and possibly CP3? I just got the engine out and will begin tear down soon. I have plans on re seating all of the injector sleeves. All parts possible I’m going to use my ultrasonic cleaner on to save money on replacement. I did buy a fass to install before first start.
I did get heavy black smoke on high RPM take off and driving heavy but nothing that makes me believe they are bad. Just would like to keep from tearing back into it soon after install.


Sent from my iPhone using Tapatalk

 

[Bdsankey]

Do you know how many miles are on the injectors?

It wouldn't hurt to tune the truck back to sock as it should not black smoke on an OEM file.

 

[Charp30]

I take that back I was pulling a trailer and it went into limp mode and shut down on me. I got a P1094 code (related) but it seemed fine afterwards so I decided a line was kinked or similar. That’s when I got the FASS system. The truck went down before I could investigate further. It doesn’t like pulling at all power wise.
I’m coming from a line of Cummins trucks btw.


Sent from my iPhone using Tapatalk

 

[Charp30]

It does have a efi 5 position switch that I never attempted to use. I am going stock minus oil cooler.


Sent from my iPhone using Tapatalk

 

[Charp30]

I do not know much about it. All I was told is that the engine was replaced with one from an ambulance 60k miles ago.


Sent from my iPhone using Tapatalk

 

[Bdsankey]

The only reason I ask is OEM injectors don't tend to live much past 70-100k miles. The newer Bosch updated nozzle design seems to get beyond that and SAC is better yet.

I would hate for you to spend 25% of fresh Bosch reman price just for you to be told they're junk. Did the truck have any idle haze?

P1094 is a low rail pressure code. Under load that means either the CP3 is weak or the injectors are returning too much fuel. A lift pump may buy some time if it's a weak pump but it's not the be-all-end-all cure.

As for oil cooler, the 17-19 is direct bolt in (minus some new bolts) and uses the same filter but is a pretty decent cooling upgrade. 20+ is a bigger yet but requires a different elbow (easy) and takes the newer filter.

 

[Charp30]

So SAC00 injectors and CP3 would be a well worth investment in its current state? Or could I get by with one or the other for a while? Was just trying to be cheap I suppose.

On a side question, while I have the LB7 on stand. Is there anything to check or replace that anyone would recommend off hand?


Sent from my iPhone using Tapatalk

 

[Charp30]

I was looking at banks oil cooler but I am looking at going with the ‘20 cooler. Would I have to buy the elbow for a ‘20 as well?


Sent from my iPhone using Tapatalk

 

[Bdsankey]

So here's my opinion, key word is my opinion, if I didn't know mileage on the injectors/questioned their health and had a P1094 code pop up before doing all this work I would replace both the CP3 and injectors.

My logic is this, you're rebuilding a truck that you plan to not mess with for awhile. You've got codes for low rail pressure which comes from essentially 2 main places (assuming nothing is kinked) which is a weak CP3 or injectors with high return rates. Changing them now is really no extra work.

As for 20+ coolers, I offer a kit for $450 to your door. That's all seals/gaskets, filter, cooler, elbow, bolts etc.

2020 Oil Cooler Retrofit Kits (01-19)

I have created a prepackaged kit for 01-19 trucks to install the 20+ GM oil cooler. I am going to be retailing this kit at $450 to your door anywhere in the continental US. This kit will include every gasket, seal, component, 10.9 flanged hardware, thread locker, and o-ring lube to do the job...

www.duramaxdiesels.com

 

[Charp30]

I say kinked because a lot of the LP/soft fuel lines look to be cut off a roll using cheap hose clamps. I’m looking into a full pre bent kit to replace them all.

I am highly interested in your oil cooler kit when I get to that point. Great price for no guess work.

Do you recommend any full gasket kits for the LB7? Minus head gaskets. Probably going to go ahead and send the heads off as soon as they’re pulled. Not even certain they need pulled but while I’m there new gasket and studs.

As for injectors and CP3 I’m half tempted to clean them up as good as I can and see what happens at least till I can afford to drop 3k at once. Assuming there is no obvious problems. I wasn’t having any noticeable hazing and the FASS might help the CP3 some. Not ideal but cost is high thru Christmas with half a dozen kids. Takes a little while to catch up lol


Sent from my iPhone using Tapatalk

 

[Charp30]

After reading your bumped post about the oil cooler kit I’ll probably go ahead and order it next week to ensure I get one.


Sent from my iPhone using Tapatalk

 

[Bdsankey]

I say kinked because a lot of the LP/soft fuel lines look to be cut off a roll using cheap hose clamps. I’m looking into a full pre bent kit to replace them all.

I am highly interested in your oil cooler kit when I get to that point. Great price for no guess work.

Do you recommend any full gasket kits for the LB7? Minus head gaskets. Probably going to go ahead and send the heads off as soon as they’re pulled. Not even certain they need pulled but while I’m there new gasket and studs.

As for injectors and CP3 I’m half tempted to clean them up as good as I can and see what happens at least till I can afford to drop 3k at once. Assuming there is no obvious problems. I wasn’t having any noticeable hazing and the FASS might help the CP3 some. Not ideal but cost is high thru Christmas with half a dozen kids. Takes a little while to catch up lol


Sent from my iPhone using Tapatalk

That's a solid plan. Just monitor the fuel system and see how things go. If it's not making oil, not hazing, and holding rail pressure you should be fine. If it starts doing any of those things (making oil, hazing, or dropping rail under load) it's time to replace some parts.

After reading your bumped post about the oil cooler kit I’ll probably go ahead and order it next week to ensure I get one.


Sent from my iPhone using Tapatalk

I'll shoot you a message!