C15 Acert Ticking Sound

Listen closley the air compressor.my Pete does the same for the last year.no problems yet.

 

Run the engine at the RPM it makes the noise, then take a bar at the left side of the head and against your skull, listen start at the front, and go to the back. Then put the bar at the top of the block, front to back, then at the oil pan edge, in line with the main bearings. You can find the area of the noise, it could be a leaking injector tip a cylinder cut out test should find this if the noise will stay when other injectors are cut out sometimes changing the delivery of fuel a little will change everything.
I would cut apart the oil filter, looking for posible piston damage, and you want to be sure when they checked over the springs and did the set did they check the cam and followers. You have to feel the cam for damage in every set position. Every lobe and follower!
You also have to check the exhaust manifold for a posible broken exhaust tube piece rattling around. Noise can travel a long way, and be very deceiving, listen at the air compressor loaded and unloaded.
Just a thought!

 

Most likely a damaged roller or cam,possibly just a over head but pretty rare also not sure about mxs cats but some years c15 have issues with braking rocker shaft bolts

 

I use a length of heater or garden hose for a stethoscope.

I've pinpointed many a tick, hiss, etc, that way.

 

Check the exhaust manifold. When mine first started leaking in sounded like an old chevy 350 with a lifter tap. The best cure is a PDI manifold if it's leaking.

 

If you had the overhead run and everything is good up there, check the exhaust manifold and turbo gaskets. The turbo mounting gaskets are pretty common. The exhaust gaskets are all too common as well, usually #3 top, the short stud will come loose first. When the engine is cold, you can reach that stud from the top, if you can turn the spacer by hand, the stud is loose.

Another really common thing is the short 1" hose for the air compressor inlet on the left side. That hose blows and it makes a ticking noise only when the compressor is unloaded. So if it starts ticking when the air dryer kicks, look there 1st.

Rocker studs are known to break and there are upgraded studs for that issue. I would have that checked if you've never had that done. Cat only replaces as they fail, but running with a shaft loose case chaff the head where the shaft sits and ruin the head, so we upgraded all of our Acerts to be safe.

 

you should be able to see black around the gasket or around the slip joints