6.2 Intake Thumping noise help?

[2INSANE]

Hello! My 6.2 Diesel in my m1009 started making a thumping sound coming from the intake manifold on the passenger side. It starts up and runs great, but after the motor warms up it starts to make a thumping sound and loses power. I was reading it could be valve springs broken or valves stuck? Has anyone ever experienced this? Solutions? Please, any advice is helpful

 

[gringeltaube]

Sounds like a sticking exhaust valve...

Loosen the injector line nuts, one by one to identify the faulty cylinder. That side rocker arm cover needs to come off. Then inspect that cylinder's parts, looking for anything obvious, like a bent push-rod; broken spring; broken rocker arm shaft; etc.
Next step would be removing the rocker arm assembly and improvise some kind of lever to be able to push down on the exhaust valve stem to make sure it moves freely, down- and back up.
Of course, the crank may have to be turned a bit, if that piston was to close to TDC.

Exhaust valves normally take an oil-seal, which makes it very difficult to get some lubricant between stem and guide, past the seal.
I have had success with it, but only after disassembling the valve retainer/locks and remove the spring.



G.

 

[2INSANE]

Ok thank you for your info! I'll start taking her apart and see what's going on