d12 engine problem

[niko]

I have 06 volvo d12 engine, the head was rebuild and now there is some strange noise - it's difficult to say if it's metal pease hitting something or compressed air comming out of somewhere. I asked the mechanic to redo the tune up he checked everything under the valve cover but everything looks normal. it sounds like a watch..... click-click-click and goes up and down with RPM. Have u guys seen something like this ? the compression test is normal, i also shut off all the injectors - one by one with computer, the noise is still there, same with egr valves... i don't know what to do ?

[Taildragon]

I have 06 volvo d12 engine, the head was rebuild and now there is some strange noise - it's difficult to say if it's metal pease hitting something or compressed air comming out of somewhere. I asked the mechanic to redo the tune up he checked everything under the valve cover but everything looks normal. it sounds like a watch..... click-click-click and goes up and down with RPM. Have u guys seen something like this ? the compression test is normal, i also shut off all the injectors - one by one with computer, the noise is still there, same with egr valves... i don't know what to do ?

Does part of your engine come in under the dash with a doghouse cover? It sounds like the gasket isn't quite sealed in the doghouse and your are hearing the rear cylinder valves, the doghouse is usually the last thing put on after a lot of work, and you are usually getting tired, and it is hard to get your body in to the right shape to get down there to install the doghouse, and it is sometimes hard to get the gasket sealed just right.

[bravoo67]

have exactly the same sound after engines overhaul.. what is dog house, is there a seal too??

[Taildragon]

have exactly the same sound after engines overhaul.. what is dog house, is there a seal too??

The dog house is the engine cover that is on the inside of the cab down below the dash, it usually has four lever style snaps that hold it in position. If you have one of the trucks where the engine extends back under the cab a ways it will usually have a doghouse, or I guess it would be called an engine cover or cowling, they all have gaskets, and it is hard to get them sealed exactly right after you have removed them, it just takes a lot of patience to get them exactly in position. It can be done though.

[Taildragon]

have exactly the same sound after engines overhaul.. what is dog house, is there a seal too??

The gasket is the seal, usually an odd shaped extruded foam rubber that attaches to the cab, and the cover sets right down against the seal and is snapped in to position.

[bravoo67]

Thank you! wasn sure but now I know what to look for