Boost Measurement

[R D Young]

I'm trying to get measurements on turbos and/or blowers. The engines are DD 12-71 TAB, which I'm told means "turbo, aftercooler, and bypass." The BoatDiesel guys said I can't get a reading from the individual turbos and that I should hook into the airbox after the blowers and coolers. The picture shows the suggested place - I get 0.00 psi there, and everywhere else I connect a gauge.

Even if that were to work, it wouldn't tell me anything about the individual turbos.

Any ideas - anyone?

Boost Connection.jpg

[Avenger]

The engines need to be loaded for the turbos to produce pressure. RPM by itself won't do anything.

[jim rosenthal]

I think you would need two boost gauges per engine. You might want to look at Turbocators, which also measure EGT- another useful piece of information on turbocharged marine diesels. And he's exactly right (he deals with this stuff all the time); you won't see any rise in boost pressure or EGT until the engines are operating under load.

[kelpy]

You would have to pick up the pressure somewhere between the turbos and the blowers. Once past the blowers, the airbox pressure is common to both sources. A said above, the engines will have to be fully loaded to generate any boost pressure..

[rustybucket]

You def shouldn't get zero there, but that's the airbox drain right? Want to make sure that stays open.

[SKYCHENEY]

You def shouldn't get zero there, but that's the airbox drain right? Want to make sure that stays open.

I think he's going to put the gauge before the check valve. That shouldn't hurt anything but, as stated, I don't think its going to give him what he's looking for as its after the blower.