I bought a 2004 GMC 2500HD lb7 Duramax with 235,000 miles on new head gaskets and 60,000 miles on the injectors. Truck is clean no blow by great shape no worries had people look at it before I purchased no concerns. 38 days of owning I have a knock within the engine. I let the truck warm up for 20-30 minutes jumped in it going not even 15 down my drive way knock started. Shut down right away checked oil, leaks anything off, checked the fan as well if something was hitting but its definitely a loud knock. Mechanic I showed the video to said its not a rod or bearing possibly in the head? Looking for answers as I think it is a clogged injector possible. Its not stuck open there is no black smoke when running. Any ideals on the issue. pushrod bent, rocker arm? Trucks all stock.
LB7: Engine knock possible in the head??
- Thread starter Colt456
- Start date
I have the same problem. Need advice on how to check balance rates. Please talk to me like I am 3 yrs old. 
) What do I need to buy to check balance rates? Cheers, Rich 2003 3500 CC 4wd LT low mileage keeper
) What do I need to buy to check balance rates? Cheers, Rich 2003 3500 CC 4wd LT low mileage keeper
Cts monitor is cheap and easy to see balance rates. Or a good scanner.
An injector going bad, or bad can/will knock and more then likely smoke or stink like raw fuel coming out of tailpipe.
Sent from my iPhone using Tapatalk
An injector going bad, or bad can/will knock and more then likely smoke or stink like raw fuel coming out of tailpipe.
Sent from my iPhone using Tapatalk