Does the Cat 3116 have a waste gate?

[Boat Guy]

I'm feeling like I should know this answer but I can't find anything online.

I was under the impression that all turbos had waste gates to manage pressure. Yet, when I did my install, I didn't see anything, nor anyway to bypass....

Thoughts? Drawings?

 

[aerobat77]

https://www.catengine.info/workshop/3126/3116-and-3126-truck-engines-turbocharger-adjusting.html

hope this helps !

 

[ttmott]

Nope - not for the marinized versions.

 

[Boat Guy]

Well, I couldn't find it...that explains it...So I guess we don't need to regulate it....Is there a boost graph to verify operation is within spec?

Thanks

I'm considering adding a boost gauge.

 

[ttmott]

Well, I couldn't find it...that explains it...So I guess we don't need to regulate it....Is there a boost graph to verify operation is within spec?

Maybe but boost pressure is directly related to load on the engine. If, for example, you throttle to high idle (engine rated RPM) in neutral then boost will essentially be zero PSIG as the engine is doing no work; conversely, running at the same RPM in gear there will be significant boost due to the heat of work. So, if there is a graph it would be based upon the engine torque as rated at a given power setting. There are too many variables to equate a graph to actuals that you would measure.

 

[Boat Guy]

Thanks, interesting info.....Well, if you were capturing data of EGT, RPM, Boost, Fuel flow, I'm thinking you could pickup signs of problems and overall health.

I wonder why they decided not to put a waste gate on. I'd have to guess that boost pressure are low even at max rated load? RPM governor? I guess it would take a major failure like a runaway engine to cause an issue?

I wonder if any members have added these instruments.

 

[yobub]

Well, I couldn't find it...that explains it...So I guess we don't need to regulate it....Is there a boost graph to verify operation is within spec?

Is this what you are looking for?

 

[Boat Guy]

Thanks, but no... I have that info....I was looking for turbo boost specs.

 

[ttmott]

I wonder why they decided not to put a waste gate on. I'd have to guess that boost pressure are low even at max rated load? RPM governor? I guess it would take a major failure like a runaway engine to cause an issue?
.

You might be surprised - As high as 2.7 bar (~40 PSI). The boost pressure is fed into the governor which then in combination with the engine's RPM and throttle position sets the fuel rack for the total fuel to be injected. The governor also limits RPM and boost by it's settings. This is unique to the mechanical engines. Unlike diesel engines driven on the roads marine are more of a constant speed engine consequently, for most applications, do not require boost regulation. So, what is the limitation? Turbocharger size and trim and the fuel delivery to the engine. This is essentially how they make several different power ratings for a common engine.