Cracking 100% Nozzles

[6.0 Tech]

Ok, so i decided to screw with the truck, as apparently mid 12s was too slow... It now has a KC Stage 2 hi pressure, S476 low pressure, Strictly bowl derete, Air Dog 2 4g, Warren 250/100 7mm hybrids, and a bunch of other chit... On stock rods and stock style pistons. Anyway, about a month ago, truck cracked a nozzle. Had a new one thrown on and went on my merry way. About 2 weeks later, cracked another. Pulled all 8 and shipped them to Warren, along with the previously broken one. They found 4 more cracked nozzles, and said it appeared they were getting too hot. I guess the nozzles were blued they said.

What would cause this? Truck seemed to run kinda hot cruising, like 850-900@ 75, but at the end of the 1/4 was turning 1400-1500. I can peg the gauge at 1600 at times, but dont most hi horsepower race trucks and pulling trucks see over 2000 constantly and have no issues?

Oh tuning by idp, running xtreme street to keep the timing out of it and save rods... Last broken nozzle was on tsd tuning, but the amage could have been done before, as i had only about 50 miles since changing tunes.

 

[ghohouston]

Fuel pressure hodling steady?

 

[6.0 Tech]

Yeah fuel pressure rock solid at 55psi. No water in a fuel sample, clean filters and oil.

 

[sideactiondiesel]

hmm.....

 

[Zeb]

Here are a few thought and questions.
Where are you measuring fuel pressure? At the pump, at the regulator, or somewhere else? The bluing you are seeing is not from egt. It is typically from fuel starvation.
Usually when I’ve seen nozzles crack it is from contamination in the fuel, too much pin travel, and/or poor metal quality in the nozzle itself.
You say your fuel sample is clean, so that is good. I would expect it to be a combination of fuel starvation to the injectors, and/or a bad batch of nozzles, because I seriously doubt that pin travel has been increased, unless the bottom of the spring cage is worn excessively.

 

[6.0 Tech]

Here are a few thought and questions.
Where are you measuring fuel pressure? At the pump, at the regulator, or somewhere else? The bluing you are seeing is not from egt. It is typically from fuel starvation.
Usually when I’ve seen nozzles crack it is from contamination in the fuel, too much pin travel, and/or poor metal quality in the nozzle itself.
You say your fuel sample is clean, so that is good. I would expect it to be a combination of fuel starvation to the injectors, and/or a bad batch of nozzles, because I seriously doubt that pin travel has been increased, unless the bottom of the spring cage is worn excessively.

Fuel pressure is measured at the regulator, which is after the injectors. Using an auto meter gauge and sending unit. I was just going off what warren said on the nozzles, i didnt inspect them that close, as i was sending them out.

 

[Zeb]

That is the best place to measure pressure, and you are using quality parts to do the measuring, so I think starvation has been ruled out.
I think it is most likely a nozzle quality issue. There is the chance however, that the sprin cage is worn and that allows too much pin travel. I saw that on a set of 190/30,s that I built from Alliant Power cores (they seem to be the worst for spring cage wear). I built the injectors, and a couple months later sold the truck. About a month after I sold it, it cracked a nozzle. It had 0.004” deep wear pattern on the bottom of the spring cage. Replaced it, and 2 months later another cracked nozzle. I told the boy to send me all the injectors and low and behold, the injector with the cracked nozzle had 0.004” deep wear, and 5 others were 0.002-0.003” deep. Replaced all the worn cages and it has been nearly 2 years and no more cracked nozzles.

 

[6.0 Tech]

Welp, got the injectors back and in finally, made it 1500-2000 miles, and broke another one... Checked fuel, as i had gotten fuel the night before, no water or any funny stuff from the separator. Fuel pressure still held steady, oil had the same amount of time on it as the injectors, as i have been changing it with each broken nozzle due to possible fuel dilution. This time all miles were on tsd spd tune. Someone shoot me now...

 

[DEEZUZ]

Ugh...

Put in some clear lines to check for air

 

[DEEZUZ]

Clear line on feed and one on return

 

[6.0 Tech]

Yeah, thats the plan now. Just driving me insane as i had no issues with holders 190/30 and 205/30 for about 45k and only switched to go to these with the compounds, and now these dont last 2k...

 

[Zeb]

I really don’t think it is air in the fuel. I will bet just about anything that it is a nozzle quality issue that Warren’s have no control over, especially if it is a nozzle that has been in this set since the issue started.

 

[Zeb]

Sent you a pm.

 

[Petro]

I have over 100k on a set of Warren 190/100's without a single nozzle issue. I've seen 1800 to 2000° exhaust temps countless times and they've been starved of fuel pressure a majority of their life. Absolutely no nozzle issues at all. I have replaced two of the injectors themselves because of failed or sticky spool valves but I'm not complaining because they have been abused terribly. I find it hard to believe it could be a heat issue causing your problem.

 

[DEEZUZ]

Gotta be air

 

[Zeb]

When I say it is a nozzle quality issue, I want to be clear that it it is a nozzle MANUFACTURING quality issue, not a quality issue with Warren’s injectors. I’m fairly certain this is something they have little control over. If you ever look inside a Redat or Poltron nozzle with a bore scope, or something similar, and look at the surface finish, quality of machine work, etc, and compare it to a Siemens or Continental nozzle it becomes evident quickly that the aftermarket nozzles are not the same quality as the OE. Anyway, I’m starting to sound like a broken record. I’ll hush now and wait for the OP to update on whether or not he finds air in the fuel.

 

[Jwarren]

How is your return run off your RR does it go to the tank or back to the Airdog-II. It would seem to me your fuel may be over heating. We have not seen an issue with nozzles cracking on 250-100’s. Really strange. I’d say fuel is over heating or air is getting into the fuel.

 

[6.0 Tech]

Unfortunately my dumb ass forgot to bring my 12mm allen home, so its gonna have to wait till either this week or next weekend to do the air test. I dont want to risk hurting the motor any running it with a cracked nozzle

How is your return run off your RR does it go to the tank or back to the Airdog-II. It would seem to me your fuel may be over heating. We have not seen an issue with nozzles cracking on 250-100’s. Really strange. I’d say fuel is over heating or air is getting into the fuel.

Im not 100% sure how the return runs. There is a y in the supply supposedly for air removal, but i also have the stock return line hooked to the sender in the tank, so it returns to the tank somehow. Ill roll under there when im checking for air and get a better answer.

In my mind, the only place for air to enter is pre pump, if i had a leak post pump, it would have an external leak, even if it was a spot for it to suck air with pressure behind the fuel, it would leak external, correct?

 

[Jomax]

Unfortunately my dumb ass forgot to bring my 12mm allen home, so its gonna have to wait till either this week or next weekend to do the air test. I dont want to risk hurting the motor any running it with a cracked nozzle







Im not 100% sure how the return runs. There is a y in the supply supposedly for air removal, but i also have the stock return line hooked to the sender in the tank, so it returns to the tank somehow. Ill roll under there when im checking for air and get a better answer.



In my mind, the only place for air to enter is pre pump, if i had a leak post pump, it would have an external leak, even if it was a spot for it to suck air with pressure behind the fuel, it would leak external, correct?

Go buy a 12mm Allen lol. Get er done!


Sent from my iPhone using Tapatalk

 

[6.0 Tech]

Well got the drivers bank of injectors swapped this weekend, windowed the tip on #6, i dont have the balls to look in the cylinder.... I guess ignorance is bliss or something like that? Anyway, finally got stuff to check for air, pulled the return where it would go into the factory fuel pump, and no air in the fuel. The way the air dog is setup, the suction and discharge side is damn near undoable without getting custom clear quick connect hoses made. But i figure no air in the return, in theory, means no air on suction or discharge.

The return is setup with a y where the factory pump return inlet is, and there is an airdog hose that also connects to it, then the single end of the y goes to return oitlet from the factory pump. The air dog return has some sort of flow there, as i had to connect a hose to it as well to keep from pissing all over my driveway.

So i guess ill get the passenger side changed and see what happens. If this is a fuel heat issue, do i need to install a fuel cooler somewhere? Is it cylinder temps overheating the nozzles? Im ****ing lost here....