I've got a tapping noise in the top of my engine. It sounds like a lifter tap on a gasser. Took it into the shop and they are GUESSING I had something go thru one of my exhaust valves and damage it. They are telling me they think it is a broken piston ring that went up thru. What else can break off in there besides an injector tip? Runs fine as far as I can tell, just has that tapping noise.

 

You know all these engine have a certain amount of clicking, ticking, clacking, banging, tingling, rapping, barking, dinging, as they are diesels. There is no way I can evulate from afar, but much worry and money has been expended in many instances with no improvement. We tend to get a fixation on a noise and it keeps worring use worse till we go bonkers.
Noise qualigaction: can you hear it very noticable in cab with radio on reasonable level??? If no, probablly nothing to worry about unless gets worse.
Broken ring would mean the piston is toasted and definitelly have a baddddd miss/noise/smoke. Damaged valve would be noticable at exhaust outlet and cause a puffing/popping.
My estimation is "the shop" would not have let it out without some fanfare if had serious condition. JMHO and again I'm not there and listening.

 

there is definitely a huffing noise in the exhaust that you can hear. I know they are loud and all that... but this is a much louder tapping noise than usual. You can hear it in the cab, and it gets louder with higher rpm. The shop wants to keep it until they can look further into it. No smoke out the exhaust and no miss that I can feel.

 

Just an idea but you could get an oil sample and send it to Blackstone labs. They may be able to determine if there is some problem in the motor like metals, carbon from rings leaking and other things.

 

I would imagine that if the piston ring broke and went through the exhaust valve or if the tip of the injector broke off you would have more than a knock in the engine. At 17:1 compression and the tight tolerences these engines run it would be dead by now or at the very least you would have a cracked head. So you you notice a huge problem while driving if it would drive at all. One thing that can cause ticking is valve adjustment being off. Sometimes the rocker arm bolts will lossen just a bit and cause a tapping sound. Take it to a Cummins repair facility and have them run the valves and check out the knock, but I doubt it is a major failure in the engine.

 

I hope you are correct!!!! I had the valves done already- hoping that is what it was...

 

mine has knocked since new in one way or another. cold weather the worst, timing I would imagine. a cummins repair shop would be your best bet for a well trained diesel ear and tech, most dodge dealers have 1 diesel guy.

 

hey I'm new to the site, so I would like to say hi first...mine taps like a gasser, but only at start up for a few minutes. sounds just like a single rocker on a chevy 350 out of adjustment. drives me nuts but truck runs strong. so I had cummins run the overhead, still taps!

 

Does the noise seem to be coming from the top front of the engine? If so, it could be normal noise from backlash between the injection pump gear and the gear that drives it. This noise gets worse as the engine breaks in / loosens up. Is your truck low mileage? If this is the cause of the noise it is not a problem, but some have been able to minimize it. If you search this site you should be able to find more info.
Ted

 

evidently I have a bad exhaust valve and #'s 1 and 2 intake valves are leaking. He is pulling the head tomorrow and seeing if the cylinder is scored on the bad exhaust valve cylinder. ugh

 

If that's the case, I'm betting on a valve seat dropping out of the head.

 

Mine has a noticable tick when cold too but it goes away in just a few minutes. 30,000 miles on the clock, done it since day one. Runs strong and pulls hard with only black smoke when I mash down hard so I figure no need to worry. I do feel like the black smoke is alittle excessive for being stock but thats for a different discussion. I'd say though if you're really concerned it's best to have it checked out. I agree with the others though, if it was a ring or something serious there would be no doubt in your mind that you had a REAL problem.

 

Ding Ding Ding Ding!!!! We have a winner! Head sent in to check for cracks and fix the seat. Top of the piston is a little rough, but not bad.