i put a set of injectors in a 3306 and maybe 40 hours on the machine #1 injector blew the tip. new cat and reman injectors were and still are on backorder through are dealer so i installed a set of aftermarket injectors. so what's the thought on the cause, poor chinese manufacturing or maybe dirt entry in a fuel line on reassembly, something else?
Usually, it’s water that blows the tips off. But, it could also be the Chineseium alloy the manufacturer used. A couple more high quality pics from different angles might help our failure analysis expertz determine a root cause.
No water in the hole just fuel
Unfortunately those photos don't show enough detail to even hazard a guess. It really needs something from much closer showing the fracture face.
There was never any water in the fuel. According to all my customers. But, since it was only one tip, that probably rules out water.
Will get a photo under the microscope Monday
In my sailor days we had Detroits in all the boats but one. When I first got assigned to the ship we had the dreaded stuck fuel rack syndrome hit all the time. The snipe on the boat would have to pull the valve cover and find which injector got smoked and disconnect it from the rack in order to shut down the engine. All this while the man at the helm ran the boat in circles to hold the speed down and not run into anything tougher than the boat. We would always find a nozzle with the tip missing and usually it was stuck in the piston. It was usually too small to hurt anything for awhile until it worked loose and then got stuck in a valve. There were drain valves on the bottom of the fuel tanks that were there to drain the water. Now the water that got in there wasn't from the fuel tanks in the ship. There were high dollar coalescer/filters that would pull water molecules out before the fuel got pumped into something. It was required because at times we had to fuel up helicopters. I got sent to a school while on that ship and learned a few things about fuel. It turns out that the water might not even be visible to a human eye to be enough to explode the tips. We had a treated test filter setup where we could suck a sample of fuel through and then put the filter under a black light. Any water would show up purple. You couldn't tell there was any water by looking at the sample through a glass jar. We concluded that our mess was condensation from the sea air. It has been a very seldom occurrence through the rest of my career to see the tips blown off injectors since my navy days. What you can do is pull the secondary fuel filter and look at the paper. A new filter will have straight pleats on every fold. Water in the fuel will make the paper expand and the paper will be wavy. If there is a lot of water you can pour out the left over fuel in the can into your palm. Water will be in the form of small balls that are a different color than the fuel.
Interesting, very good info!
best i can do
Hard to tell but a few signs on the fracture faces lead me to believe that it was a material failure. Wouldn't stake my life on it though.
That's what I'm going with. cut the filter and no signs of water from what i can tell but not out of the question. years ago the cat dealer had a hand full of tips blow off on the dyno and they where all chalked up to manufacture defect.
Looks like excessive inclusion content in the grain structure - dirty metal. Recycled soup cans and highway guard rails. ????