Has anyone had any problems with boschs new design injector? I found my major fuel leak and it was one if the reman fuel lines from industrial which I'll never get anything from there again. The injectors are remans through merchant auto, and at night if I take a flashlight and hold it at the right angle I can see all sorts of gray smoke when I rev it up a big ploom of white comes out. The guy who did the install said its very unlikely for them to be bad even though I keep smelling a strong diesel smell at red lights.
LB7: Possibly injectors?
- Thread starter kking
- Start date
if your balance rates are good and there is no diesel in your oil or white/grey/blue smoke at idle during the daytime then you are okay for now.
The injectors can still fail./ Ball seat erosion has been adressed but there is no cure for the cracked bodies.
The injectors can still fail./ Ball seat erosion has been adressed but there is no cure for the cracked bodies.
Strong diesel smell from exhaust is kind of a big time indication of injector trouble. Can you see white smoke at warm idle in the day time? Ever checked balance rates? Superswamper, what tests did you do to see the condition of your injectors? The lb7 does vent the crankcase to the atmosphere on the underside of the front of the engine. I smell this sometimes, it is not quite a raw diesel smell but can be somewhat similar.
You are mistaken on the injector body, they have been updated and you don't hear too much about new one's cracking. The ball seat erosion has been "addressed", but they have proven to still fail at a faster than normal rate, as in leaking excess fuel with high return rates and white smoke at idle.
I checked the balance rates and most I had on the new injectors was 3.2 and -2.3, last weekend I did the return test and had 35ml for both banks. The white smoke isn't visible during the day at all figured since its a lb7 and no emissions. I used my mighty vac and pulled my return lines into a 15hg vacuum and pressurized them to 15psi. I'm still making oil though. I had found one bad reman fuel line thinking I might have another one leaking
They all cough spit and smoke, your balance rates aren't too bad. how many miles on this "new" set?
Couple questions. did you replace the high pressure lines when you did this? if there is any kind of debris on the line or the seal on the valve cover when the line is inserted through the valve cover it could easily fall down onto the top of the injector and cause a non sealing issue on the high pressure side of the injector. this would be pretty tough to tell. IDK if it would work but before you change your oil you might try to loosen them one at a time and flush anything out of that area with fuel while its running and retorque them while running and then change oil and see if that cures it. might be worth a shot.
I just checked the balance rates out on my cts, and they are all within spec. But I didnt know what you said about the lb7 vent thing
35ML for both banks is way to high. GM says the max is 30, and that is pushing it for what a stock CP3 can hold. And balance rates do NOT tell you if your injectors are bad or not, they are a diagnostic aid is all. And most people forget the most important part of checking balance rates which is what is the fuel rate when you check them. If all your injectors are going the balance rates can be perfect, but the fuel rate will go down. With the engine warm(175+ engine temp with the oil warmed up), the fuel rate at idle should be 8-9MM3 of fuel at 680RPM's. If it is say 5 then you have to add 3 to all your balance rates. All of the sudden that -2 becomes a -5, but on the other hand that 3 becomes a 0. Balance rates are simply +/- how far off the average fuel rate each injector is. So if they are all bad, then the fuel rate will show it but the balance rates will all look fine.
The high pressure lines were installed when the injectors were done, and since then I replaced the one bad one I found that was pitted and should have never been sold. As far as the return lines I have checked them and know there not leaking. didn't know if 35ml was high or not I was just going off a page I read that would make sense to much fuel returning because I'm loosing my prime a little not enough to where I have to reprime it the truck kinda surges when I fire her up.
Not sure why I missed it but I just saw above that you put the return system under vacuum. I also forgot you already adressed high pressure lines. Brain wasn't working well.
I missed where you said 35ml too. That is borderline. They say if it is over that, continue testing injectors, if under that and rail pressure is still suffering, replace CP3. Rail pressure is not your issue though.
You need to figure out a way to test the banks individually. I just use a GM kit I found on craigslist used for $100, they are $600 new. Its stupid, but you need a way to connect to the banjo bolts on the outside. I have also just taken extra return lines and cut the ends off the attached hoses. Find the bank returning excess fuel and go from there. You can then remove the valvecovers, attach to each individual injector, reattach fuel system and see which injector is the culprit.
Between 3-5ml per injector depending on API rating of fuel is gm's spec.
Haven't really got to far since the last time, been going round and around with my truck long story short I'm pretty sure it's the injectors but they said I can try a diff set of injector lines and if that doesn't help me all the injectors are coming out and going back to merchant.
that's really not that bad, the 3.6 is getting close but depends if your in gear or not. I had one come in not too long ago and he was +10 told him and explained and he said no big deal and kept driving it. had a pretty good knock at idle. I thought they came from industrial
The injectors came from merchant but the lines had come from industrial. I called merchant and told them about everything they said as many times as I have taken the lines off the fitting on the injector body may have come undone idk if that's likely to happen or not?