Waste gate on 3176 Cat

[Boatingfool]

Have you ever had your turbine clearances inside the housing checked?

Doug

Doug,

Haven't checked this, but there are no signs visible (ie. abnormal sound or impeller dust in intake piping) that would make me think she's out of spec.

Basically, she's acting similar to a high power turbocharged car... more laggy and not as quick in the high temps.

 

[Boatingfool]

From turbo car experience a waste gate is a servo that opens a reliefe valve on the pressure side of the turbo once a preset boost level is reached thus "wasting" the extra boost. This can be a small can looking thing with a rod coming out of it attached to a lever on the actual valve. Again I have no knowledge of diesel operation but figured I could help you locate where the wastegate is for investigational purposes!
Here is a link to a wastegate that should resemble the one on your engines, if so equipped.
http://www.jscspeed.com/srt4/turbo/agp_wga.htm

Great description! That is very similar to most factory vehicles which have internal wastegate actuator(s). The diesel engines I'm most familar with (Volvo 480's, Cummins 450's and QSM's, and the MAN diesels) have external style wastegate(s). Here is a link to his style:

http://www.hksusa.com/images/?id=1377

In short, the wastegate regulates how much exhuast gas that is exiting the engine goes through the turbine side of the turbocharger. The more exhuast gas that goes through the turbine spings the turbo faster, which makes more boost.

To regulate or not run to much boost, the wategate opens and diverts the exhaust gases around the turbocharger. Less air through the turbine doesn't allow the turbo to spin as fast, thus creating less boost (air flow).

 

[douglee25]

Doug,

Haven't checked this, but there are no signs visible (ie. abnormal sound or impeller dust in intake piping) that would make me think she's out of spec.

Basically, she's acting similar to a high power turbocharged car... more laggy and not as quick in the high temps.

In your season downtime, I would have this inspected. You may need to send them out to have them serviced. Another possibility is that these turbos were sized too large for the application. Stepping down to a smaller turbo may actually increase your performance because they spool up faster.

Doug

 

[earthmover17]

Everyone seems to be familar with a lot of engines with wastegates BUT the cat. If you know the Cats Respond.
Jack Ensley