First off, I am new to this site. This seems to be a pretty nice site.
I am a diesel mechanic at a caterpillar dealer. This is the second lb7 I have put injectors in. The truck was smoking real bad. I replaced all 8 injectors. It does not smoke anymore, but Now there is a fuel knock coming from the injector on the driver's side, third injector from the front. The knock goes away when the fuel line is disconnected. I did a compression test already. I have 440lbs on all four on the driver's side. I thought I got a bad reman injector, so I replaced it again. Still knocks after replacing it again. I did notice however, When I was replacing it the second time the injector was stuck real bad in the cup. It had lots of carbon in the cup. It took a while to clean it out. Do I have a problem with the injector cup?
Balance rates:
At cold idle
Bal Rate 1 (mm3) -1.2
Bal Rate 2 (mm3) 6.5
Bal Rate 3 (mm3) -2.5
Bal Rate 4 (mm3) 1.0
Bal Rate 5 (mm3) -4.0
Bal Rate 6 (mm3) 0.7
Bal Rate 7 (mm3) 1.7
Bal Rate 8 (mm3) .2

Warmed up at idle
Bal Rate 1 (mm3) 1.0
Bal Rate 2 (mm3) 3.0
Bal Rate 3 (mm3) -2.7
Bal Rate 4 (mm3) .8
Bal Rate 5 (mm3) -1.0
Bal Rate 6 (mm3) .7
Bal Rate 7 (mm3) .8
Bal Rate 8 (mm3) -1.0
any suggestions?

 

#2 & #5 at idle look a bit high for new injectors. where did you get them from?

 

Pensacola diesel

 

Pensacola!!!

Well there's your problem

Pensacola diesel is not well know for producing reliable products. there is a reason that their's are as cheap as they are. contact a reliable source: Merchant, Lincoln diesel, etc to get your injectors.

if i had to guess, you likely got more then one injector that was out of spec. your #5 is likely dumping too much fuel, hence the knock, and the ecm is trying to tone it down. the ecm is probably trying to keep the idle smooth by adding extra fuel on #2 to balance the #5 out.

Give Brent at Lincoln Diesel a call 920-765-1615 and explain your situation to him. he will help you out.

 

Just ask Danny about Pensacola Injectors. I think he went through 3 or 4 sets

Luke

 

Thanks for the info. The thing I don't get is why is cylinder 6 knocking?

 

I looked it over some more today. Still trying to determine where the coolant is going. Every time I warm the engine up I have to add coolant to it after it cools down again. Warmed the engine to normal operating temp, and took it for a spin. I squeezed the radiator hose after I got home and the hose was very soft. I pulled the cap off of the coolant reservoir and there was black residue on the side walls of the tank. It Does not smell like diesel in the tank though. I turned the engine off and heard a gurgling sound coming from the area around cylinder 6(the one that is knocking) Is it possibly that I am getting coolant into the cylinder? Thing I don't understand is that the compression is good on that cylinder, and there is no compression going into the cooling system. Any ideas?

 

check the compression on all cylinders. #6 may not really be the one