3208 making a chuff-chuff-chuff sound

[ajo]

turbo´d 3208 recently began making a chuff-chuff-chuff sound at the air intake. Seems to be in step with other normal sounds related to idle speed rotation. When I hold my hand over the air intake I can feel a distinct drop in suction pressure at each chuff.

There appears to be no untoward vibration at idle. At 1000 rpm the chuffing appears to be still in step with watching the engine rotate and there is still no vibration.

When the motor is working there is a related ticking/dipping in turbo boost pressure.

What´s likely to have gone wrong? The motor has a few hundred hours on it and I have perhaps 50 hours to go to home port. What risk of further damage? Oil pressure, temperature, fluid levels all look ok.

Any comments/help would be great and appreciated.

Thanks, ajo

[Cat]

Does it do it as you shut the engine off too? Check your valve adjustments. You could have a tight valve adjustment or worse yet a burnt valve. If the adjustment is too tight it will hold the valve open and give you the chuf-chuf noise-- so will a burnt valve.

[ajo]

Report from the home port garage: We have the valve covers off now and found one intake valve stem an inch higher than all the others. The rocker arm is broken. So that is the bad cylinder that was causing the chuff-chuff sound. What next? Well, now we are in the process of removing the motor from the bus so it will be easier to pull the heads and see what further damage there is. There are several other similar motors here so we may be able to mix and match for parts. One question I have is are the heads the same for turbo'd and natural motors? There are a couple of pictures available but I'm not sure if I have attached them properly.

[Cat]

I do not remember a difference between turbo and non turbo heads. Pistons yes big difference, block yes different. If this gets worse you might want to look at an exchange engine.
I would exchange the engine before letting someone local try to put a repair sleeve in. This does engine does not have " cylinder liners". Putting a repair sleeve in takes a really good machine/engine shop to do it. I hope it does not come to that. But just from the picture I'm worried that you have piston and cylinder damage.
I'll keep my fingers crossed that its just a head repair. Good luck.