I hooked the compressor back up and isolated it to the #5 exhaust rocker. I loosened it up all the way and got the leak slow down but it didn't quit. So I loosened em all up and nothing changed. So it has to be valve seats leaking. If that's the case, just send it in and have it completely gone through along with a port job? TIA! Was going to do a valve lash adjustment, but I reckon all that's going to do is waste time.



Bill

 

I take it you have the exhaust manifold off? How did you suspect cylinder leakdown? The last thread I knew about was you thought you were losing coolant. A leaking valve guide/seal is far from coolant leaking. Did I miss a thread?

 

I built a leak tester that clamps to the compressor side of the turbo, then sent 25 lbs. through the system. It was blowing back out through the oil fill hole on the valve cover. So I loosened all the rocker arms, starting with #5. I don't think it's leaking past the rings, cause it runs good with the exception of a slighly rough idle, probably due to leaking valve seats and or guides. Doesn't smoke, uses hardly any oil, doesn't get overfull.

 

I see. Well, you could always pull number 5 injector and leak that cylinder down to tell for sure. With the kind of cylinder pressures these days you would think a leaking valve seat/guide would be more noticeable than that.

 

Here is another little test you can try. Do you have a compression tester? I would highly reccomend you do that before you go drastic. Anyways compression test the cylinder you think it is. If the compression is low try this. Pour about a tablespoon of oil into the cylinder. This will help seal the rings. If the compression goes up It's more than likely something is wrong on the bottom end, piston,rings liner. If it remains mostly the same then it is probably a head problem. The problem with your tester is that any open intake ports will let the air past the valve seals as no seal is perfect. Especially since it is also missing its oil film which will help it seal. A better way would be to put that cylinder a TDC compression and apply air pressure to that cylinder only.

Just something to think about. It's better to go through all the possibilities before you send it off just incase it turns out that wasn't the problem.

 

Here's a video.


http://s209.photobucket.com/albums/bb292/CTB06/?action=view&current=MOV00267.flv

 

I think I might hear a dead spot that kind of moves around a little but not too sure. Other than that it sounds normal. It could the camera sound going in and out as you move around is what I'm hearing too. It's hard to tell. I know my truck has changed pitch with the more miles I put on it. It has really loosened up and makes boost much faster, runs much better but has gotten a little louder it seems. The 06's had valve problems though so I hate to say it's nothing. Seems if you get them hot and added too much timing they didn't respond well. I know quite a few that "dropped" valves. Not saying that's what happening here but I would hate for that to happen as you have a chance to fix it now with no damage yet. The guys at G and J in Billings are supposed to be good diesel guys. I know it's a ways from Baker but might be worth a shot.